CONTROL DEVICE, CONTROL METHOD, AND CONTROL SYSTEM

Abstract

In order to specify and instruct to where to move an object in order to form the object in a shape that allows the object to be easily excavated, a control method includes: acquiring information pertaining to a deposition state of the object deposited; specifying a destination of the object in an excavation target region with reference to the acquired information pertaining to the deposition state; and instructing an excavator to move the object to the destination.

Description

TECHNICAL FIELD

The present invention relates to a control apparatus, a control method, and a control system.

BACKGROUND ART

Utilization of robots is attracting attention as a measure for dealing with a decrease in the number of workers due to an aging population with a low birth rate and for dealing with an increase in workload due to a shortage of labor. For example, in the construction industry, it is urgent to enhance productivity through labor saving. This raises great expectations for automation of work with use of construction machines.

For example, Patent Literature 1 discloses a control system that determines a smoothed current landform from a smoothed height for each of a plurality of points so as to move a work machine along a virtually designed landform determined on the basis of the current landform.

CITATION LIST

Patent Literature

• • [Patent Literature 1]
  • Japanese Patent Application Publication, Tokukai, No. 2018-021348

SUMMARY OF INVENTION

Technical Problem

At a work site, in a case where excavation work with use of a work machine is carried out and excavation can be carried out with an object to be excavated made easily excavatable, it is possible to achieve higher work efficiency. However, no such control technique has been known.

For example, the technique disclosed in Patent Literature 1 makes it possible to move the work machine along the virtually designed landform, but is not intended to make an object easily excavatable.

An example aspect of the present invention is to provide a technique that makes it possible to achieve higher work efficiency by making an object easily excavatable.

Solution to Problem

A control apparatus according to an example aspect of the present invention includes: an acquisition means that acquires information pertaining to a deposition state of an object deposited; a specification means that specifies a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and an instruction means that instructs an excavator to move the object to the destination.

A control method according to an example aspect of the present invention includes: (a) acquiring information pertaining to a deposition state of an object deposited; (b) specifying a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and (c) instructing an excavator to move the object to the destination.

A control system according to an example aspect of the present invention includes: an acquisition means that acquires information pertaining to a deposition state of an object deposited; a specification means that specifies a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and an instruction means that instructs an excavator to move the object to the destination.

Advantageous Effects of Invention

An example aspect of the present invention makes it possible to achieve higher work efficiency by making an object easily excavatable.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating a configuration of a control apparatus according to a first example embodiment of the present invention.

FIG. 2 is a flowchart illustrating a flow of a control method that is carried out by the control apparatus according to the first example embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration of a control system according to the first example embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration of a control apparatus according to a second example embodiment of the present invention.

FIG. 5 is a flowchart illustrating a flow of a control method that is carried out by the control apparatus according to the second example embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of a control system according to the second example embodiment of the present invention.

FIG. 7 is a block diagram illustrating a configuration of a control system according to a variation of the second example embodiment of the present invention.

FIG. 8 is a diagram illustrating a specific example of an excavation operation carried out by a backhoe according to the second example embodiment of the present invention.

FIG. 9 is a diagram illustrating a specific example of the excavation operation carried out by the backhoe according to the second example embodiment of the present invention.

FIG. 10 is a flowchart illustrating a work process for excavation and movement of an object according to the second example embodiment of the present invention.

FIG. 11 is a detailed flowchart specifying an origin and a destination in FIG. 10.

FIG. 12 is a diagram illustrating movement of an object according to a third example embodiment of the present invention.

FIG. 13 is another diagram illustrating movement of the object according to the third example embodiment of the present invention.

FIG. 14 is another diagram illustrating movement of the object according to the third example embodiment of the present invention.

FIG. 15 illustrates a first example of a specific evaluation method for evaluating ease of excavation according to a fourth example embodiment of the present invention.

FIG. 16 illustrates a gradient evaluation function that is used in the first example of the evaluation method.

FIG. 17 illustrates a second example of the specific evaluation method for evaluating ease of excavation according to a fifth example embodiment of the present invention.

FIG. 18 illustrates a height evaluation function that is used in the second example of the evaluation method.

FIG. 19 illustrates a third example of the specific evaluation method for evaluating ease of excavation according to the fifth example embodiment of the present invention.

FIG. 20 illustrates a gradient evaluation function that is used in the third example of the evaluation method.

FIG. 21 illustrates a fourth example of the specific evaluation method for evaluating ease of excavation according to a seventh example embodiment of the present invention.

FIG. 22 illustrates a height evaluation function that is used in the fourth example of the evaluation method.

FIG. 23 is a configuration diagram for achieving a control apparatus etc. by software.

DESCRIPTION OF EMBODIMENTS

First Example Embodiment

A first example embodiment of the present invention will be described in detail with reference to the drawings. The present example embodiment is an embodiment serving as a basis for example embodiments described later. A control apparatus 1 according to the present example embodiment is an apparatus that controls an excavator. An excavator that excavates an object deposited is to be controlled in the present example embodiment and is exemplified by a backhoe. Excavation as used in the present example embodiment refers to using, for example, a bucket of an excavator to scoop off the object deposited on, for example, the ground. A type of the object is not limited. Examples of the object include soil, sand, snow, grain, and cement. The object encompasses an object that is granular or irregularly shaped and that is capable of being scooped off with use of a bucket. A place at which the object is deposited is also not limited.

The following description will discuss wordings used in the present example embodiment. First, the expression “raking” is sometimes used in the present example embodiment. Note here that “raking” refers to making an object easily excavatable by moving the object. “Raking” can also be more specifically expressed as “operation of improving ease of excavation at a point A and/or a point B by moving the object at the point A to the point B”. In the above expression, movement includes the meaning of movement in either a horizontal component or a vertical component. Note, however, that the wording “raking” does not limit the present example embodiment. In the present example embodiment, “raking” is also sometimes simply expressed as “movement”.

In the following example embodiments, the wording “raking region” refers to a region in which the object is deposited and in which raking with use of a bucket of an excavator is capable of being carried out. Specifically, “raking region” is defined as a range that is reachable by a bucket attached to a tip of an arm of an excavator.

The wording “excavation target region” refers to a region which is a part of the raking region and in which excavation is capable of being carried out. More specifically, for example, “excavation target region” refers to a region which is a part of the raking region and in which it is possible to carry out excavation without changing a position of the excavator. As another example, “excavation target region” refers to a region which is a part of the raking region and in which it is possible to carry out excavation with use of a bucket, without changing a position of the excavator in a translational direction, by at least one selected from the group consisting of turning, movement of the arm, and movement of a boom. The wording “excavation range” herein refers to a region which is a part of the excavation target region and through which the bucket passes during excavation. For example, an excavation operation is carried out by the excavator such that the bucket is pushed into the object at a position far from the excavator, and then the bucket is moved linearly toward the excavator so as to scoop the object. Thus, the excavation range that is viewed from above (viewed in a plan view) has, for example, a rectangular shape in which a set of long sides is parallel to a direction toward the excavator. The length of a short side of the excavation range is the width of the bucket, and the length of a long side is the distance traveled through the object by the bucket.

An average gradient of the height in the excavation range refers to a gradient from a position farthest from the excavator (far position) toward a position nearest to the excavator (near position) in the excavation range, the gradient being calculated from a difference between (a) a height of the object at the far position and (b) a height of the object at the near position and a difference in horizontal distance between the far position and the near position. Since the far position and the near position are located on respective opposite sides of a rectangle, the heights at the respective far and near positions are expressed as average heights, and a gradient determined from a difference between the average heights and from a difference in horizontal distance between the far position and the near position is referred to as an average gradient.

(Configuration of Control Apparatus 1)

A configuration of the control apparatus 1 according to the first example embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a block diagram illustrating the configuration of the control apparatus 1. As illustrated in FIG. 1, the control apparatus 1 includes an acquisition section 10, a specification section 11, and an instruction section 12. Note that the acquisition section 10 is an example embodiment of an acquisition means recited in the claims. The specification section 11 is an example embodiment of a specification means recited in the claims. The instruction section 12 is an example embodiment of an instruction means recited in the claims.

The following description will discuss configurations included in the control apparatus 1. The acquisition section 10 acquires information pertaining to a deposition state of an object deposited. The information pertaining to the deposition state of the object is, for example, information on the basis of which a height of the object deposited can be derived. The height of deposition, for example, is the height from a lowest part of the deposition (e.g., the ground, if the object is deposited on the ground) to a certain point on a surface of the object. Hereinafter, the height of the object deposited (height in a case where an upward direction in the vertical direction is positive) is simply referred to as “height”. However, the expression “height” may not necessarily refer to the height from a specific place but may also be used to refer to a relative height of the surface of the object. Further, in the present specification, the expression “depth of an object” may be used. In other words, an object having a large height may be expressed as having a large depth, and an object having a small height may be expressed as having a small depth.

The information pertaining to the deposition state of the object is, for example, distance information measured with use of a three-dimensional camera or a distance measuring apparatus such as three-dimensional light detection and ranging (Lidar). The distance information is information including a direction and a distance to a certain point. Heights at respective points on the surface are derived from a direction and a distance from the distance measuring apparatus to the surface on which the object is deposited. Furthermore, a gradient of the surface is also derived from the heights at the respective points. Note that it is assumed that a height of a mounting surface on which the object has not been deposited is measured in advance. Alternatively, it is assumed that the object is deposited so deep that a position of the mounting surface is negligible. A method in which the acquisition section acquires the distance information is not limited. For example, the acquisition section 10 acquires the distance information from the distance measuring apparatus with use of wired communication, wireless communication, or a combination thereof.

The specification section 11 specifies a destination of the object in the excavation target region, the destination being in accordance with the deposition state. For example, the specification section 11 refers to the information pertaining to the deposition state and specifies, as the destination of the object, a point at which the height and/or the gradient of the object satisfies/satisfy a predetermined condition in the excavation target region. The predetermined condition may be, for example, a condition that the height is lower in the excavation target region than at another point.

The instruction section 12 instructs the excavator to move the object to the destination specified by the specification section 11. Specifically, in order to move the object to the destination, the instruction section 12 generates a control signal for moving the arm of the excavator and transmits the control signal to an arm driving section of the excavator.

In the example embodiment illustrated in FIG. 1, the acquisition section 10, the specification section 11, and the instruction section 12 are described as being incorporated in the single control apparatus 1. Note, however, that the acquisition section 10, the specification section 11, and the instruction section 12 do not necessarily need to be incorporated in a single control apparatus. For example, all or some of the acquisition section 10, the specification section 11, and the instruction section 12 may be disposed separately. The acquisition section 10, the specification section 11, and the instruction section 12 may be connected to each other via wired communication or wireless communication. For example, all or some of the acquisition section 10, the specification section 11, and the instruction section 12 may be present on a cloud. This point also applies to an apparatus configuration described below.

(Effect Brought about by Control Apparatus 1)

As described above, the control apparatus 1 according to the present example embodiment employs a configuration such that information pertaining to a deposition state of an object deposited is acquired, a destination of the object in an excavation target region, the destination being in accordance with the deposition state, is specified, and an excavator is instructed to move the object to the destination.

In general, in a case where an excavator is used to excavate an object, progress of excavation reduces the object and results in lower excavation efficiency due to formation of unevenness on a surface of the object. It is therefore preferable to smooth the unevenness of the surface and move the object to a position at which the object is easily excavatable. According to the control apparatus 1 according to the present example embodiment, a destination of an object in an excavation target region is specified with reference to information pertaining to an acquired deposition state, and an excavator is instructed to move the object to the destination. This makes it possible to form the object in a shape that allows the object to be easily excavated.

Thus, the control apparatus 1 according to the present example embodiment brings about an effect of achieving higher excavation efficiency.

(Flow of Control Method S1)

Next, a flow of a control method S1 according to the present example embodiment will be described with reference to FIG. 2. FIG. 2 is a flowchart illustrating a flow of the control method S1 that is carried out by the control apparatus 1. As illustrated in FIG. 2, the control method S1 includes the following steps. First, in a step S10 (acquiring), the control apparatus 1 acquires information pertaining to a deposition state of an object deposited. For example, the acquisition section 10 can acquire distance information measured by a distance measuring apparatus. Note that a method in which the acquisition section 10 acquires the distance information is not limited. For example, the acquisition section 10 acquires the distance information from the distance measuring apparatus with use of wired communication, wireless communication, or a combination thereof.

Next, in a step S11 (specifying), the control apparatus 1 specifies a destination of the object in an excavation target region, the destination being in accordance with the deposition state. For example, the specification section 11 specifies, with reference to information pertaining to the deposition state and acquired in the step S11, the destination of the object in the excavation target region.

Next, in a step S12 (instructing), the control apparatus 1 instructs an excavator to move the object to the destination. For example, the instruction section 12 instructs the excavator to move the object to the destination specified in the step S11.

(Effect of Control Method S1)

As described above, the control method S1 according to the present example embodiment employs a configuration such that the control apparatus 1 acquires information pertaining to a deposition state, specifies a destination of the object in an excavation target region, the destination being in accordance with the deposition state, and instructs an excavator to move the object to the destination. This makes it possible to form the object in a shape that allows the object to be easily excavated.

Thus, the control method S1 according to the present example embodiment brings about an effect of achieving higher excavation efficiency.

(Configuration of control system 2)

Next, a configuration of a control system 2 according to the first example embodiment will be described with reference to FIG. 3. FIG. 3 is a block diagram illustrating the configuration of the control system 2. As illustrated in FIG. 3, the control system 2 includes an acquisition section 21, a specification section 22, and an instruction section 23. Since the acquisition section 21, the specification section 22, and the instruction section 23 of the control system 2 are equivalent to the acquisition section 10, the specification section 11, and the instruction section 12, respectively, of the control apparatus 1 described earlier, a description thereof is omitted. The control system 2 controls a backhoe (excavator) 200. Specifically, the control system 2 acquires information pertaining to a deposition state of an object 300 deposited, specifies a destination of the object 300 in an excavation target region, the destination being in accordance with the deposition state, and instructs the backhoe 200 to move the object 300 to the destination. The control system 2 is communicably connected with a controller 201 of the backhoe 200 via a communication network 100.

(Effect of Control System 2)

As described above, the control system 2 according to the present example embodiment employs a configuration such that information pertaining to a deposition state of an object deposited is acquired, a destination of the object in an excavation target region, the destination being in accordance with the deposition state, is specified, and an excavator is instructed to move the object to the destination. This makes it possible to form the object in a shape that allows the object to be easily excavated.

Thus, the control system 2 according to the present example embodiment brings about an effect of achieving higher excavation efficiency.

Second Example Embodiment

A second example embodiment of the present invention will be described in detail with reference to the drawings. Note that members having functions identical to those of the respective members described in the first example embodiment are given respective identical reference numerals, and a description of those members is not repeated. Note also that definitions of the phrases defined in the first example embodiment will not be described again in the following description.

(Configuration of Control Apparatus 3)

A configuration of a control apparatus 3 according to the present example embodiment will be described with reference to FIG. 4. FIG. 4 is a block diagram illustrating the configuration of the control apparatus 3. As illustrated in FIG. 4, the control apparatus 3 includes an acquisition section 30, an evaluation section 31, a specification section 32, and an instruction section 33. Since the acquisition section 30 and the instruction section 33 of the control apparatus 3 are equivalent to the acquisition section 10 and the instruction section 12, respectively, of the control apparatus 1 described earlier, a description thereof is not repeated. The evaluation section 31 is an example embodiment of an evaluation means recited in the claims. The specification section 32 is an example embodiment of the specification means recited in the claims.

The evaluation section 31 evaluates ease of excavation of an object with reference to information pertaining to a deposition state. Ease of excavation of the object refers to easiness to excavate the object. For example, the evaluation section 31 carries out evaluation such that the object which has a flatter surface increases ease of excavation and such that the object which has a more uneven surface lowers ease of excavation. For example, the evaluation section 31 derives heights of the object at a plurality of points on the basis of information pertaining to a deposition state of the object, and on the basis of the derived heights at the plurality of points, calculates, as an indicator indicative of ease of excavation, an evaluation value representing a degree of unevenness of the surface of the object.

The specification section 32 specifies a destination with reference to the ease of excavation evaluated by the evaluation section 31. For example, among a plurality of destination candidates, the specification section 32 specifies, as the destination, a destination candidate for which a result of evaluation by the evaluation section 31 satisfies a predetermined condition. For example, the specification section 32 specifies, as the destination, a destination candidate for which a result of evaluation of the ease of excavation by the evaluation section 31 is relatively low. In this case, the result of evaluation has a positive correlation with the ease of excavation. That is, a low result of evaluation of the ease of excavation means that the object is more difficult to excavate.

(Effect Brought about by Control Apparatus 3)

As described above, the control apparatus 3 according to the present example embodiment employs a configuration such that ease of excavation of an object is evaluated with reference to information pertaining to a deposition state, and a destination of the object is specified with reference to the evaluated ease of excavation. Thus, by moving the object to the destination that is specified with reference to the ease of excavation of the object, the control apparatus 3 according to the present example embodiment brings about an effect of achieving higher excavation efficiency.

(Flow of Control Method S2)

Next, a flow of a control method S2 according to the present example embodiment will be described with reference to FIG. 5. FIG. 5 is a flowchart illustrating a flow of the control method S2 that is carried out by the control apparatus 3. As illustrated in FIG. 5, the control method S2 includes steps S20 to S23. Since the steps S20 and S23 among the steps S20 to S23 are similar to the respective steps S10 and S12 of the control method S1 described earlier, a description thereof is not repeated.

In the step S21, the evaluation section 31 evaluates ease of excavation of an object with reference to information pertaining to a deposition state. For example, the evaluation section 31 derives heights of the object at a plurality of points on the basis of information pertaining to a deposition state of the object, and on the basis of the derived heights at the plurality of points, calculates, as an indicator indicative of ease of excavation, an evaluation value representing a degree of unevenness of the surface of the object.

In the step S22, the specification section 32 specifies the destination with reference to the ease of excavation. For example, among a plurality of destination candidates, the specification section 32 specifies, as the destination, a destination candidate for which a result of evaluation by the evaluation section 31 satisfies a predetermined condition. For example, the specification section 32 specifies, as the destination, a destination candidate for which a result of evaluation of the ease of excavation by the evaluation section 31 is relatively low.

(Effect of Control Method S2)

As described above, the control method S2 according to the present example embodiment employs a configuration such that ease of excavation of an object is evaluated with reference to information pertaining to a deposition state, and the object is moved with reference to the evaluated ease of excavation. Thus, by moving the object to the destination that is specified with reference to the ease of excavation of the object, the control method S2 according to the present example embodiment brings about an effect of achieving higher excavation efficiency.

(Configuration of Control System 4)

Next, a configuration of a control system 4 according to the present example embodiment will be described with reference to FIG. 6. FIG. 6 is a block diagram illustrating the configuration of the control system 4. As illustrated in FIG. 6, the control system 4 includes a control apparatus 40 and a sensor 202. The control apparatus 40 includes an acquisition section 41, an evaluation section 42, a specification section 43, an instruction section 44, a communication section 46, and a memory 47. Since the acquisition section 41, the evaluation section 42, the specification section 43, and the instruction section 44 of the control apparatus 40 are equivalent to the acquisition section 30, the evaluation section 31, the specification section 32, and the instruction section 33, respectively, of the control apparatus 3 described earlier, a description thereof is not repeated.

The control apparatus 40 is communicably connected with a controller 201 of a backhoe 200 and the sensor 202 via a communication network 100. The communication section 46 of the control apparatus 40 carries out data communication between the controller 201 and the sensor 202. In the present example embodiment, communication is carried out via wireless communication, but may be carried out via wired communication. The wireless communication may be, for example, long term evolution (LTE), local 5G, 5G, or Wi-fi (registered trademark). Note that the controller 201 may be mounted on the backhoe 200 or may be disposed at a position different from a position at which the backhoe 200 is disposed.

The memory 47 temporarily or non-temporarily stores, for example, various programs and various kinds of data, each of which is referred to by the control apparatus 40.

The backhoe 200 is an excavator and rakes the object 300. The backhoe 200 is operated by the controller 201 that has received an instruction from the control apparatus 40.

The sensor 202 measures information pertaining to a deposition state of the object 300 deposited. The sensor 202 may be a three-dimensional camera or a distance measuring apparatus such as three-dimensional Lidar as described earlier. Data from the sensor 202 is acquired by the acquisition section 41 via the communication section 46. The sensor 202 is disposed at a position at which heights of the deposited object 300 at all points can be measured. The sensor 202 is disposed at a position at which an area in which the object is deposited is viewed from above, such as a ceiling, a column, or a beam.

(Configuration of Control System 5)

Next, a configuration of a control system 5 according to a variation of the present example embodiment will be described with reference to FIG. 7. FIG. 7 is a block diagram illustrating the configuration of the control system 5. As illustrated in FIG. 7, the control system 5 includes a first control apparatus 50, a second control apparatus 60, and a sensor 202.

The first control apparatus 50 includes an acquisition section 51, an evaluation section 52, a communication section 53, and a memory 54. Since the acquisition section 51, the evaluation section 52, the communication section 53, and the memory 54 of the first control apparatus 50 are similar to the acquisition section 41, the evaluation section 42, the communication section 46, and the memory 47, respectively, of the control apparatus 40 described earlier, a description thereof is not repeated.

The second control apparatus 60 includes a specification section 61, an instruction section 62, a communication section 63, and a memory 64. Since the specification section 61, the instruction section 62, the communication section 63, and the memory 64 of the second control apparatus 60 are similar to the specification section 43, the instruction section 44, the communication section 46, and the memory 47, respectively, of the control apparatus 40 described earlier, a description thereof is not repeated.

In the control system 5 according to the present variation, the first control apparatus 50 includes the acquisition section 51 and the evaluation section 52, whereas the second control apparatus 60 includes the specification section 61 and the instruction section 62 (see FIG. 7). The control system 5 according to the present variation is thus configured such that a configuration in which the evaluation value is calculated and a configuration in which the destination of the object is specified are present in a system in a distributed manner. Even such a configuration brings about an effect similar to the effect brought about by each of the example embodiments described earlier.

Note that a method of distributing sections in the system is not limited to the above example, and another method of distributing the sections may be employed.

(Specific Example of Excavation Operation)

FIGS. 8 and 9 are each a diagram illustrating a specific example of an excavation operation carried out by the backhoe 200 according to the second example embodiment. FIG. 8 illustrates an example of a state in which the excavation operation carried out by the backhoe 200 is viewed from above. In FIG. 8, a region a21 is a raking region in which raking with use of a bucket 200a of the backhoe 200 is capable of being carried out. A region a22 is an excavation target region in which it is possible to carry out excavation with use of the bucket 200a, without changing a position of the backhoe 200 in a translational direction, by at least one selected from the group consisting of turning, movement of an arm, and movement of a boom. In order to facilitate understanding of the invention, the example of FIG. 8 illustrates a case where the raking region a21 and the excavation target region a22 each have a rectangular shape. However, the shape of the raking region a21 and the excavation target region a22 is not limited to that illustrated in FIG. 8. The raking region a21 and the excavation target region a22 may each have another shape that is different from the rectangular shape.

An excavation range a23 is, as described earlier, a range through which the bucket 200a passes in the excavation operation. As described earlier, the backhoe 200 pushes the bucket 200a into the object at an excavation point p21 far from the backhoe 200, and then linearly moves the bucket 200a in a direction toward the backhoe 200 so as to scoop the object 300. This causes the excavation range a23 to have a rectangular shape in which a set of long sides is parallel to the direction toward the backhoe 200. Note that a direct distance (long side of the excavation range a23) for which the bucket 200a is moved during excavation is determined in accordance with a capacity of the bucket 200a and an amount of deposition of the object.

FIG. 9 is a diagram illustrating the excavation operation carried out by the backhoe 200, as viewed from an arrow A1 direction in FIG. 8. In FIG. 9, a height D at the excavation point p21 is a height of the object 300 in a case where an arrow H direction (upward direction in the vertical direction) is positive. An average gradient G in the excavation range a23 indicates a gradient from a far position p21 toward a near position p22 in the excavation range a23, the gradient being calculated from (i) an average height at the excavation point p21 that is the far position in the excavation range a23 and (ii) an average height at the near position p22 in the excavation range a23.

(Work Process for Excavation and Movement)

FIG. 10 is a flowchart illustrating a work process S3 that is carried out by the control apparatus 40 according to the second example embodiment and that is an example work process for excavation and movement of an object.

In a step S30, the acquisition section 41 acquires the information pertaining to the deposition state of the object 300. The information pertaining to the deposition state includes, for example, the height of the object 300 and information pertaining to a gradient of the height of the object. For example, the acquisition section 41 acquires, via the communication section 46, information indicative of a result of measurement by the sensor 202.

The information that is acquired by the acquisition section 41 includes, for example, information indicative of the height of the object 300 at each of a plurality of points included in the excavation target region a22. The plurality of points included in the excavation target region a22 may be, for example, a plurality of points arranged in a grid pattern for each predetermined unit distance. The predetermined unit distance may be, for example, several tens of centimeters. In this case, each of regions arranged in a grid pattern is referred to as a “point”. The “height” at the point may be represented by, for example, an average height of heights measured in a region, or may be represented by a height at a certain position (e.g., a central part) in the region. For example, “excavation point p21” described earlier may be a region around the excavation point p21, the region being one of the regions arranged in a grid pattern. In the following description, the plurality of points included in the excavation target region a22 are also referred to as a plurality of “excavation points”.

In a step S31, the evaluation section 42 derives the height D and the average gradient G at each of the excavation points with reference to the information acquired in the step S30.

(Derivation of Average Gradient G)

For example, the evaluation section 42 derives, by the following method, the average gradient G at the excavation point p21 included in the excavation target region a22. First, the evaluation section 42 specifies the excavation range a23 corresponding to the excavation point p21. The excavation range a23 corresponding to the excavation point p21 is a range through which the bucket 200a passes in the excavation operation in which the backhoe 200 pushes the bucket 200a into the excavation point p21 and linearly moves the bucket 200a in the direction toward the backhoe 200 so as to scoop the object 300. In other words, the excavation range a23 corresponding to the excavation point p21 is a range represented by a rectangle in which a set of long sides is parallel to the direction toward the backhoe 200 and in which one of short sides passes through the excavation point p21. In this case, the excavation point p21 is the far position in the excavation range a23, and a position on an opposite side of the short side passing through the excavation point p21 is the near position p22 in the excavation range a23. In the following description, the excavation point p21 is also referred to as the far position p21 in the excavation range a23.

Next, the evaluation section 42 derives (i) an average height D1 at the far position p21 in the specified excavation range a23, (ii) an average height D2 at the near position p22 in the excavation range a23, (iii) a distance L1 from the backhoe 200 to the far position p21, and (iv) a distance L2 from the backhoe 200 to the near position p22.

The average gradient G is an average gradient of the height of the excavation range a23 in the direction toward the backhoe 200 and is represented by the following Equation (G1):

G=(D2−D1)/(L1−L2)  (G1a)

Alternatively, expression of the above equation in degrees)(°) results in the following:

G(°)=arctan{(D2−D1)/(L1−L2)}  (G1b)

In a case where the far position in the excavation range a23 is a short side including the excavation point p21 as in the example embodiment illustrated in FIG. 8, the average height D1 at the far position in the excavation range a23 may be the average height at the excavation point p21. However, the present invention is not limited to such a configuration. The average height L2 at the near position p22 in the excavation range a23 may be, for example, an average height in the regions arranged in a grid pattern and including the near position p22 in the excavation range a23. However, the present invention is not limited to such a configuration.

In a step S32, the evaluation section 42 derives an evaluation value representing ease of excavation of the object 300. Note here that the evaluation value is, as described above, a value representing ease of excavation. For example, a greater evaluation value indicates that excavation at the point is easier, and a smaller evaluation value indicates that excavation at the point is more difficult.

In this example, the evaluation section 42 evaluates ease of excavation with reference to the height of the object 300 and the gradient of the height of the object. More specifically, for example, for each of a plurality of excavation points p21 included in the excavation target region a22, the evaluation section 42 derives the evaluation value with reference to the average height D1 and the average gradient G in the excavation range a23 corresponding to each of the excavation points p21, the average height D1 and the average gradient G each having been derived in the step S31.

Furthermore, for example, the evaluation section 42 may evaluate ease of excavation with reference to an evaluation value concerning the average gradient G of the height in the excavation range a23 and an evaluation value concerning the average height D1 at the far position in the excavation range a23 and the average height Dx in the excavation target region a22.

Note that the evaluation value derived by the evaluation section 42 is not limited to the example described above, and may be a value derived by another method. For example, the average gradient G in the excavation range a23 corresponding to each of the excavation points p21 may be used as the evaluation value. The evaluation value may be, for example, an evaluation value concerning the average gradient of the height in the excavation range a23 and configured to increase as a gradient value toward the backhoe 200 is greater. For another example, a combination of the average gradient G and the average height D1 in the excavation range a23 may be used as the evaluation value.

Furthermore, for example, the evaluation section 42 may calculate the evaluation value with reference to the average gradient G in the excavation target region a22 and a difference in height ΔD (delta D). In this case, for example, the evaluation section 42 calculates the difference in height ΔD as below. First, the evaluation section 42 calculates the average height Dx in the excavation target region a22. The average height Dx in the excavation target region a22 is an average value of heights measured by the sensor 202 for each of division regions into which the excavation target region a22 has been divided.

The difference in height (difference in depth) ΔD is a difference between the average height D1 at the far position in the excavation range a23 and the average height Dx in the excavation target region a22. The difference in height ΔD is represented by the following Equation (G2):

ΔD=D1−Dx  (G2)

In a step S33, the specification section 43 determines whether the evaluation value is less than a predetermined threshold at all the excavation points p21 for which the evaluation value has been derived. In a case where the evaluation value is less than the threshold at all the excavation points p21 (YES in the step S33), the specification section 43 proceeds to a process in a step S34. In contrast, in a case where there is an excavation point p21 at which the evaluation value is not less than the threshold (NO in the step S33), the specification section 43 proceeds to a process in a step S35. In other words, in a case where the evaluation value is less than the threshold at all the excavation points p21, the control apparatus 40 proceeds to the process in the step S34 and causes the backhoe 200 to move the object 300. In contrast, in a case where the excavation point p21 at which the evaluation value is not less than the threshold exists, the control apparatus 40 proceeds to the process in the step S35 and excavates the object 300.

In the step S34, the specification section 43 specifies an origin and a destination that satisfy a predetermined condition. A process, carried out by the specification section 43 in the step S34, for specifying the origin and the destination will be described later in detail. Upon completion of the process in the step S34, the specification section 43 proceeds to a process in a step S36.

In the step S35, the instruction section 44 instructs the backhoe 200 to excavate the object 300, so that the object 300 is excavated. Specifically, in order for the object 300 to be excavated, the instruction section 44 generates a control signal for moving the arm of the backhoe 200, and transmits the control signal to the controller 201. Upon completion of the process in the step S35, the instruction section 44 proceeds to a process in a step S37.

In the step S36, the instruction section 44 instructs the backhoe 200 to move the object 300 to the specified destination and causes the backhoe 200 to move the object 300. Specifically, in order for the object 300 to move to the destination, the instruction section 44 generates a control signal for moving the arm of the backhoe 200, and transmits the control signal to the controller 201. Upon completion of the process in the step S36, the instruction section 44 proceeds to the process in the step S37.

In the step S37, the control apparatus 40 makes a determination as to whether to end the work. The determination may be made by, for example, whether a range and/or an amount of the object that has been excavated by the backhoe 200 satisfies/satisfy a predetermined condition. Note that whether to end the work does not necessarily need to be determined by the above method, but may be determined by another method. In a case where the work is to be ended (YES in the step S37), the control apparatus 40 ends the process. In contrast, in a case where the work is not to be ended (NO in the step S37), the control apparatus 40 returns to the process in the step S30.

FIG. 11 is a flowchart illustrating an example of the process in the step S34 in FIG. 10, that is, a process in which the specification section 43 specifies the origin and the destination. In this example, from among the plurality of excavation points p21 included in the excavation target region a22, the specification section 43 specifies, as the origin, an excavation point p21 that satisfies the predetermined condition.

In a step S40, from among the plurality of excavation points p21 included in the excavation target region a22, the specification section 43 specifies, as a candidate for the origin, an excavation point p21 higher than the other excavation points p21. In this case, in other words, the origin of the object 300 is a position at which the object 300 in the excavation target region a22 has a greater height than at another position. For example, the specification section 43 sets, as the origin, an excavation point p21 at which the object 300 has a greatest height. Alternatively, the specification section 43 may set, as the origin, an excavation point p21 at which the object is deposited in a larger amount than at the other excavation points p21. For example, the specification section 43 may set, as the origin of the object 300, an excavation point at which the object is deposited in a largest amount. The specification section 43 may specify, as the origin, a single candidate or a plurality of candidates.

In a step S41, from among the plurality of excavation points p21 included in the excavation target region a22, the specification section 43 specifies, as a candidate for the destination, an excavation point p21 lower than the other excavation points p21. In this case, in other words, the destination of the object 300 is a position at which the object 300 in the excavation target region a22 has a lower height than at another position. For example, the specification section 43 sets, as the destination, an excavation point p21 at which the object 300 has a lowest height. Alternatively, the specification section 43 may set, as the destination, an excavation point p21 at which the object is deposited in a smaller amount than at the other excavation points p21. For example, the specification section 43 may set, as the destination of the object 300, an excavation point at which the object is deposited in a smallest amount. Furthermore, the specification section 43 may specify a candidate for the origin from among the plurality of excavation points p21 in accordance with a distance from the excavation apparatus 200 and/or a distance to a region that is determined to be dangerous (a passage area for a worker, a traveling area for a dump truck, etc., or a building such as a watchtower). The specification section 43 may specify, as the destination, a single candidate or a plurality of candidates.

In a step S42, the specification section 43 selects, from among the plurality of candidates, the origin and the destination with reference to a distance. For example, among a plurality of destination candidates, the specification section 43 specifies, as the destination, a destination candidate that satisfies a predetermined condition. Specifically, for example, among the plurality of destination candidates, the specification section 43 specifies, as the destination, a destination candidate that has a relatively short distance traveled from the origin. For example, the specification section 43 selects, as a combination of the origin and the destination, a combination in which a distance between the origin and the destination is not more than a predetermined threshold. Note that the origin and the destination do not necessarily need to be selected by the above method, but may be selected by another method.

In a step S43, the specification section 43 determines whether the object 300 is movable. For example, the specification section 43 determines whether there is any obstacle or the like on a movement track of the bucket 200a, and determines, in a case where there is no obstacle or the like, that the object 300 is movable. Note that whether the object 300 is movable does not necessarily need to be determined by the above method, but may be determined by another method. In a case where the object 300 is movable (YES in the step S43), the specification section 43 proceeds to a process in a step S44. In contrast, in a case where the object 300 is not movable (NO in the step S43), the specification section 43 returns to the process in the step S42.

In the step S44, the specification section 43 specifies, as a combination of the origin and the destination of which combination the backhoe 200 is to be instructed, the combination of the origin and the destination, the combination having been selected in the step S42.

(Effect of Control System 4 or 5)

As described above, the control system 4 or 5 according to the present example embodiment employs a configuration such that ease of excavation of the object 300 is evaluated with reference to information pertaining to a deposition state. Thus, according to the control system 4 or 5 according to the present example embodiment, by moving the object 300 with reference to ease of excavation that has been evaluated with reference to the height of the object 300 and the gradient of the height of the object 300, it is possible to bring about an effect of forming the object 300 in a shape that allows the object 300 to be easily excavated, and achieving higher excavation efficiency.

Third Example Embodiment

A third example embodiment of the present invention will be described in detail with reference to the drawings. Note that members having functions identical to those of the respective members described in the first or second example embodiment are given respective identical reference numerals, and a description of those members is not repeated.

A control apparatus 40B according to the third example embodiment of the present invention differs from the control apparatus 40 according to the second example embodiment described earlier in details of (i) the process for specifying the origin and the destination of the object 300 (process in the step S34 in FIG. 10) and (ii) the process for moving the object 300 (process in the step S36 in FIG. 10). The following description will discuss these processes with reference to the drawings.

FIG. 12 is a diagram for describing a process for specifying an origin and a destination of an object 300 according to the present example embodiment. In this example, first, the specification section 43 specifies, as the destination (end point p32), a point at which the object 300 has a lowest height in an excavation target region a22. Next, the specification section 43 calculates a raking line L30 that connects a turning center P1 of a backhoe 200 with the end point p32. Furthermore, from among points satisfying the following three conditions, the specification section 43 specifies, as the origin (starting point p31), for example, a point at which the object 300 has a greatest height.

• • The points are located on the raking line L30.
  • The points are located in a raking region a21. The starting point may be or need not be included in the excavation target region a22. Note, however, that the starting point needs to be included in the raking region a21. Note also that the end point needs to be included in the excavation target region a22.
  • The starting point is located at a point that is not less than a predetermined distance away from the end point (because the starting point and the end point that are too close to each other bring about less raking effect). The predetermined distance can be set in consideration of various conditions.

In the example of FIG. 12, a distance between the starting point p31 and the turning center P1 of the backhoe 200 is longer than a distance between the end point p32 and the turning center P1. In this case, for example, under control by the control apparatus 40, by moving a bucket 200a along a raking line L1 from the back toward the front when viewed from the backhoe 200, the backhoe 200 carries out a raking operation with respect to the object 300 so as to move, to the front side, the object 300 that is deposited on the back side.

A positional relationship between the starting point and the end point of the raking operation is not limited to the example illustrated in FIG. 12. The starting point and the end point of the raking operation may alternatively be in a positional relationship such that the distance between the starting point and the turning center of the backhoe 200 is shorter than the distance between the end point and the turning center.

FIG. 13 is a diagram illustrating another example of the origin and the destination of the object 300 according to the present example embodiment. In the example of FIG. 13, a distance between a starting point p41 and the turning center P1 of the backhoe 200 is shorter than a distance between an end point p42 and the turning center P1. In this case, for example, under control by the control apparatus 40, by linearly moving the bucket 200a from the front toward the back when viewed from the backhoe 200, the backhoe 200 carries out a pushing operation with respect to the object 300 so as to move, to the back side, the object 300 that remains on the front side.

FIG. 14 is another diagram illustrating an example of movement of the object 300 according to the present example embodiment. In the example of FIG. 14, a distance between a starting point p51 and the turning center P1 of the backhoe 200 is longer than a distance between an end point p52 and the turning center P1. In this case, for example, under control by the control apparatus 40, by moving the bucket 200a from the starting point p51 to the end point p52 so as to draw a curve, the backhoe 200 carries out the raking operation with respect to the object 300 so as to move, to the front side, the object 300 that is deposited on the back side. As described above, the raking operation is not limited to an operation of linearly moving the bucket 200a, but may be an operation of moving the object between any two points.

Fourth Example Embodiment

A fourth example embodiment of the present invention will be described in detail with reference to the drawings. Note that members having functions identical to those of the respective members described in the first to third example embodiments are given respective identical reference numerals, and a description of those members is not repeated. The fourth example embodiment of the present invention describes a first example of an evaluation function that is used by the evaluation section 42 to evaluate ease of excavation.

FIG. 15 is an example of a diagram obtained by three-dimensionally plotting an evaluation function P for evaluating ease of excavation according to the fourth example embodiment of the present invention. The evaluation function P is a function whose variables are G, D, and Dx, and is represented by the following Expression (1):

$\begin{array}{cc}P\left(G,D\right)=\left(1-\alpha \right)·\frac{1}{1+\exp \left(-\mathrm{aG}\right)}+\alpha ·\frac{1}{1+\exp \left(-b\left(D-\mathrm{Dx}\right)\right)}& \mathrm{Expression}\left(1\right)\end{array}$ $\begin{array}{c}a=-\frac{1}{G_0}·\ln \frac{0.5-\tau }{0.5+\tau }\\ b=-\frac{1}{D_0}·\ln \frac{0.5-\tau }{0.5+\tau }\end{array}$

where: the variable G is an average gradient)(° in an excavation range, the variable D is a height (m) at an excavation point, and the variable Dx is an average height (m) in an excavation target region; and a and b are coefficients. A constant G₀ included in the coefficient a is a constant that is greater than 0 and that has a dimension of an angle (°), and a constant D₀ included in the coefficient b is a constant that is greater than 0 and that has a dimension identical to a dimension of the height (m). τ included in the coefficients a and b is a parameter satisfying 0<τ<0.5, and determines weighting of the constant G₀ and the constant D₀. α is a parameter satisfying 0≤α≤1.0, and determines weighting of a first term and a second term.

The first term in the above Expression (1) is a term that evaluates the average gradient with use of a sigmoid function. The sigmoid function is a function that transforms an input value G into a value from 0 to 1. FIG. 16 is a graph illustrating a calculated value of the sigmoid function in the first term. The average gradient G in the excavation range has a positive value in a case where the height increases in a direction toward an excavator. Thus, in a case where a is constant, a greater average gradient G causes the first term to have a greater value. Since a rising gradient that increases toward the excavator facilitates excavation, a greater average gradient G is configured to be given a greater evaluation value.

The second term in the above Expression (1) is a term that evaluates a difference in height on a surface of an object with use of the sigmoid function. As the height D at the excavation point becomes greater than the average height Dx in the excavation target region, the second term has a greater value. Excavation carried out with priority given to a point that is as high as possible makes it possible to further prevent or reduce concentrated selection of points having a low height. This makes it possible to maintain a shape that allows the object to be easily excavated. Thus, greater (D−Dx) is configured to be given a higher evaluation value. Note that also for the second term, a curve as shown in FIG. 16 is obtained by plotting (D−Dx) on the horizontal axis, though not illustrated.

As described above, a greater average gradient G and a greater height D at the excavation point result in an increase in calculated value of the evaluation function P (see FIG. 15). Note that the constants can be set, for example, as follows: G₀=20.0 (°), D₀=length (m) of bucket of excavator, τ=0.3, and α=0.2. The length of a bucket of the excavator is the length of the bucket in a direction in which an arm extends.

Fifth Example Embodiment

A fifth example embodiment of the present invention will be described in detail with reference to the drawings. Note that members having functions identical to those of the respective members described in the first to fourth example embodiments are given respective identical reference numerals, and a description of those members is not repeated. The fifth example embodiment of the present invention describes a second example of the evaluation function that is used to evaluate ease of excavation.

FIG. 17 is an example of a diagram obtained by three-dimensionally plotting an evaluation function P for evaluating ease of excavation according to the fifth example embodiment of the present invention. The evaluation function P is a function whose variables are G, D, and Dx, and is represented by the following Expression (2): Definitions of G, D, and Dx in the expression are identical to the definitions described in the fourth example embodiment.

$\begin{array}{cc}P\left(G,D\right)=\left(1-\alpha \right)·\frac{1}{1+\exp \left(-\mathrm{aG}\right)}+\alpha ·\exp \left(-{b\left(D-\mathrm{Dx}\right)}^2\right)& \mathrm{Expression}\left(2\right)\end{array}$ $\begin{array}{c}a=-\frac{1}{G_0}·\ln \frac{0.5-\tau }{0.5+\tau }\\ b=-\frac{1}{D_0^2}·\ln \left(0.5-\tau \right)\end{array}$

As compared with Expression (1) shown in the fourth example embodiment, in the above Expression (2), a first term is identical to the first term in Expression (1), and a second term is replaced with an exponential expression that is a convex function. The second term is replaced with the exponential expression because a point whose height is close to an average height Dx in an excavation target region is given a high evaluation value in order to prioritize excavation while avoiding a locally high point or a locally low point. In this case, the avoided locally high point or locally low point is flattened later by raking.

In the exponential expression (excluding a) of the second term, a value from 0 to 1 is given to an input value (D−Dx). FIG. 18 is a graph illustrating a calculated value of the exponential expression (excluding a) of the second term for evaluating the height. Note that a coefficient b in the second term is different from b shown in the fourth example embodiment. Since a calculated value of the first term shows a curve similar to the curve of the first term in Expression (1) shown in the fourth example embodiment, a description thereof is omitted.

As described above, a greater average gradient G and a height D at the excavation point closer to the average height Dx in the excavation target region result in an increase in calculated value of the evaluation function P (see FIG. 17). Note that a constant G₀, a constant D₀, τ, and α may be similar to those in the fourth example embodiment, and an example setting of the constants may also be similar to, for example, the example setting shown in the fourth example embodiment.

Sixth Example Embodiment

A sixth example embodiment of the present invention will be described in detail with reference to the drawings. Note that members having functions identical to those of the respective members described in the first to fifth example embodiments are given respective identical reference numerals, and a description of those members is not repeated. The sixth example embodiment of the present invention describes a third example of the evaluation function that is used to evaluate ease of excavation.

FIG. 19 is an example of a diagram obtained by three-dimensionally plotting an evaluation function P for evaluating ease of excavation according to the sixth example embodiment of the present invention. The evaluation function P is a function whose variables are G, D, and Dx, and is represented by the following Expression (3): Definitions of G, D, and Dx in the expression are identical to the definitions described in the fourth example embodiment.

$\begin{array}{cc}P\left(G,D\right)=\left(1-\alpha \right)·F_g\left(G\right)+\alpha ·F_d\left(D\right)& \mathrm{Expression}\left(3\right)\end{array}$ $F_g\left(G\right)=\{\begin{array}{cc}1& \mathrm{if}\frac{G_0}{2\tau }<G\\ \frac{\tau }{G_0}G+0.5& \mathrm{else}\mathrm{if}-\frac{G_0}{2\tau }\le G\le \frac{G_0}{2\tau }\\ 0& \mathrm{others}\end{array}$ $F_g\left(D\right)=\{\begin{array}{cc}1& \mathrm{if}\frac{D_0}{2\tau }+\mathrm{Dx}<D\\ \frac{\tau }{D_0}\left(D-\mathrm{Dx}\right)+0.5& \mathrm{else}\mathrm{if}\mathrm{Dx}-\frac{D_0}{2\tau }\le D\le \mathrm{Dx}+\frac{D_0}{2\tau }\\ 0& \mathrm{others}\end{array}$

Expression (3) is an evaluation formula for deriving an evaluation value with use of a linear function instead of a sigmoid function. That is, Expression (3) is obtained by replacing a sigmoid function part of Expression (1) with the linear function. More specifically, the sigmoid function part of the first term in Expression (1) described in the fourth example embodiment is replaced with a function F g (G), and the sigmoid function part of the second term in Expression (1) described in the fourth example embodiment is replaced with a function F d (D).

FIG. 20 is a calculated value of the function F g (G) in a case where the variable G in the first term is plotted on the horizontal axis. As illustrated in Expression (3) and FIG. 20, in a range of −(G₀/2τ)≤G≤G₀/2τ, the calculated value linearly increases as the variable G increases. The calculated value which is smaller than a lower limit of this range reaches 0, and the calculated value which is in a range exceeding an upper limit of this range reaches 1. That is, in Expression (3), in a region in which the variable G has a small absolute value, the calculated value changes more gradually with respect to a change in variable G than in Expression (1). Also for the function F_d(D) of the second term, in a region in which the variable D has a small absolute value, the calculated value changes more gradually with respect to a change in variable D than in Expression (1). This results in the evaluation function in which the evaluation value less changes with respect to a change in input.

As described above, a greater average gradient G and a greater height D at an excavation point result in a gradual increase, in a certain range, in calculated value of the evaluation function P represented by Expression (3) (see FIG. 19). Note that a constant G₀, a constant D₀, τ, and α may be similar to those in the fourth example embodiment, and an example setting of the constants may also be similar to, for example, the example setting shown in the fourth example embodiment.

Seventh Example Embodiment

A seventh example embodiment of the present invention will be described in detail with reference to the drawings. Note that members having functions identical to those of the respective members described in the first to sixth example embodiments are given respective identical reference numerals, and a description of those members is not repeated. The seventh example embodiment of the present invention describes a fourth example of the evaluation function that is used to evaluate ease of excavation.

FIG. 21 is an example of a diagram obtained by three-dimensionally plotting an evaluation function P for evaluating ease of excavation according to the seventh example embodiment of the present invention. The evaluation function P is a function whose variables are G and D, and is represented by the following Expression (4): Definitions of G, D, and Dx in the expression are identical to the definitions described in the fourth example embodiment.

$\begin{array}{cc}P\left(G,D\right)=\left(1-\alpha \right)·F_g\left(G\right)+\alpha ·H_d\left(D\right)& \mathrm{Expression}\left(4\right)\end{array}$ $F_g\left(G\right)=\{\begin{array}{cc}1& \mathrm{if}\frac{G_0}{2\tau }<G\\ \frac{\tau }{G_0}G+0.5& \mathrm{else}\mathrm{if}-\frac{G_0}{2\tau }\le G\le \frac{G_0}{2\tau }\\ 0& \mathrm{others}\end{array}$ $H_d\left(D\right)=\{\begin{array}{cc}1-❘\frac{\tau +0.5}{\mathrm{Dx}+D_0}D❘& \mathrm{if}❘D❘\le \frac{\mathrm{Dx}+D_0}{\tau +0.5}\\ 0& \mathrm{others}\end{array}$

Expression (4) is obtained by replacing, with a function H_d(D), the function F_d(D) of the second term in Expression (3) in the sixth example embodiment. As illustrated in FIG. 22, H_d(D) is a function in which a calculated value reaches a maximum value at Dx and decreases as D is further away from Dx. Equation (4) is an evaluation function in which as in the case of Expression (2) according to the fifth example embodiment, for the second term concerning the height, a point whose height is close to an average height Dx in an excavation target region is given a high evaluation value in order to prioritize excavation while avoiding a locally high point or a locally low point.

As described above, a greater average gradient G and a height D at the excavation point closer to the average height Dx in the excavation target region result in an increase, in a certain range, in calculated value of the evaluation function P represented by Expression (4) (see FIG. 21). Note that a constant G₀, a constant D₀, τ, and α may be similar to those in the fourth example embodiment, and an example setting of the constants may also be similar to, for example, the example setting shown in the fourth example embodiment.

[Software Implementation Example]

Some or all of the functions of each of the control apparatuses 1, 3, 20, 40, and 40B, the first control apparatus 50, and the second control apparatus 60 (hereinafter referred to as “control apparatus 1 etc.”) may be realized by hardware such as an integrated circuit (IC chip) or may be alternatively realized by software.

In the latter case, the control apparatus 1 etc. is realized by, for example, a computer that executes instructions of a program that is software realizing the functions. FIG. 10 illustrates an example of such a computer (hereinafter referred to as “computer C”). The computer C includes at least one processor C1 and at least one memory C2. The memory C2 stores a program P for causing the computer C to operate as the control apparatus 1 etc. In the computer C, the functions of the control apparatus 1 etc. are realized by the processor C1 reading the program P from the memory C2 and executing the program P.

The processor C1 may be, for example, a central processing unit (CPU), a graphic processing unit (GPU), a digital signal processor (DSP), a micro processing unit (MPU), a floating point number processing unit (FPU), a physics processing unit (PPU), a microcontroller, or a combination thereof. The memory C2 may be, for example, a flash memory, a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof.

Note that the computer C may further include a random access memory (RAM) in which the program P is loaded when executed and/or in which various kinds of data are temporarily stored. The computer C may further include a communication interface for transmitting and receiving data to and from another apparatus. The computer C may further include an input/output interface for connecting the computer C to an input/output apparatus(es) such as a keyboard, a mouse, a display, and/or a printer.

The program P can also be recorded in a non-transitory tangible storage medium M from which the computer C can read the program P. Such a storage medium M may be, for example, a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like. The computer C can acquire the program P via the storage medium M. The program P can be transmitted via a transmission medium. The transmission medium may be, for example, a communication network, a broadcast wave, or the like. The computer C can acquire the program P also via the transmission medium.

[Additional Remark 1]

The present invention is not limited to the foregoing example embodiments, but may be altered in various ways by a skilled person within the scope of the claims. For example, the present invention also encompasses, in its technical scope, any example embodiment derived by appropriately combining technical means disclosed in the foregoing example embodiments.

[Additional Remark 2]

The whole or part of the example embodiments disclosed above can also be described as below. Note, however, that the present invention is not limited to the following supplementary notes.

(Supplementary Note 1)

A control method including: (a) acquiring information pertaining to a deposition state of an object deposited; (b) specifying a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and (c) instructing an excavator to move the object to the destination.

The above configuration makes it possible to achieve higher work efficiency by making an object easily excavatable.

(Supplementary Note 2)

The control method according to Supplementary note 1, further including (d) evaluating ease of excavation of the object with reference to the information pertaining to the deposition state, wherein in (b), the destination is specified with reference to the ease of excavation.

According to the above configuration, by moving the object to the destination that is specified with reference to the ease of excavation of the object, it is possible to form the object in a shape that allows the object to be easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 3) The control method according to Supplementary note 2, wherein the information pertaining to the deposition state includes a height of the object and information pertaining to a gradient of the height of the object, and in (d), the ease of excavation is evaluated with reference to the height of the object and the gradient of the height of the object.

According to the above configuration, by moving the object to a destination that is specified with reference to the ease of excavation which is evaluated with reference to the height of the object and the gradient of the height of the object, it is possible to form the object in a shape that allows the object to be easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 4)

The control method according to Supplementary note 3, wherein in (d), the ease of excavation is evaluated with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region.

According to the above configuration, by evaluating the ease of excavation with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 5)

The control method according to any one of Supplementary notes 2 to 4, wherein in (b), among a plurality of destination candidates, a destination candidate for which a result of evaluation of the ease of excavation in (d) is relatively low is specified as the destination.

According to the above configuration, by moving the object to the destination that is specified on the basis of the result of evaluation, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 6)

The control method according to any one of Supplementary notes 1 to 5, wherein the destination of the object is a position at which the height of the object in the excavation target region is lower than at another position.

According to the above configuration, by specifying, as the destination, a position at which the height of the object in the excavation target region is lower than at another position, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 7)

The control method according to any one of Supplementary notes 1 to 6, wherein the excavation target region is a region in which the object is deposited and in which excavation is capable of being carried out.

The above configuration makes it possible to achieve higher work efficiency by making an object easily excavatable.

(Supplementary Note 8)

A control apparatus including: an acquisition means that acquires information pertaining to a deposition state of an object deposited; a specification means that specifies a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and an instruction means that instructs an excavator to move the object to the destination.

The above configuration makes it possible to achieve higher work efficiency by making an object easily excavatable.

(Supplementary Note 9)

The control apparatus according to Supplementary note 8, further including an evaluation means that evaluates ease of excavation of the object with reference to the information pertaining to the deposition state, wherein the specification means specifies the destination with reference to the ease of excavation.

According to the above configuration, by moving the object to the destination that is specified with reference to the ease of excavation of the object, it is possible to form the object in a shape that allows the object to be easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 10)

The control apparatus according to Supplementary note 9, wherein the information pertaining to the deposition state includes a height of the object and information pertaining to a gradient of the height of the object, and the evaluation means evaluates the ease of excavation with reference to the height of the object and the gradient of the height of the object.

According to the above configuration, by moving the object to a destination that is specified with reference to the ease of excavation which is evaluated with reference to the height of the object and the gradient of the height of the object, it is possible to form the object in a shape that allows the object to be easily excavated, and to achieve higher excavation efficiency.

(Supplementary note 11)

The control apparatus according to Supplementary note 10, wherein the evaluation means evaluates the ease of excavation with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region.

According to the above configuration, by evaluating the ease of excavation with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 12)

The control apparatus according to any one of Supplementary notes 9 to 11, wherein among a plurality of destination candidates, the specification means specifies, as the destination, a destination candidate for which a result of evaluation of the ease of excavation by the evaluation means is relatively low.

According to the above configuration, by moving the object to the destination that is specified on the basis of the result of evaluation, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 13)

The control apparatus according to any one of Supplementary notes 8 to 12, wherein the destination of the object is a position at which the height of the object in the excavation target region is lower than at another position.

According to the above configuration, by specifying, as the destination, a position at which the height of the object in the excavation target region is lower than at another position, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 14)

The control apparatus according to any one of Supplementary notes 7 to 13, wherein the excavation target region is a region in which the object is deposited and in which excavation is capable of being carried out.

The above configuration makes it possible to achieve higher work efficiency by making an object easily excavatable.

(Supplementary Note 15)

A control system including: an acquisition means that acquires information pertaining to a deposition state of an object deposited; a specification means that specifies a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and an instruction means that instructs an excavator to move the object to the destination.

The above configuration makes it possible to achieve higher work efficiency by making an object easily excavatable.

(Supplementary Note 16)

The control system according to Supplementary note 15, further including an evaluation means that evaluates ease of excavation of the object with reference to the information pertaining to the deposition state, wherein the specification means specifies the destination with reference to the ease of excavation.

According to the above configuration, by moving the object to the destination that is specified with reference to the ease of excavation of the object, it is possible to form the object in a shape that allows the object to be easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 17)

The control system according to Supplementary note 16, wherein the information pertaining to the deposition state includes a height of the object and information pertaining to a gradient of the height of the object, and the evaluation means evaluates the ease of excavation with reference to the height of the object and the gradient of the height of the object.

According to the above configuration, by moving the object to a destination that is specified with reference to the ease of excavation which is evaluated with reference to the height of the object and the gradient of the height of the object, it is possible to form the object in a shape that allows the object to be easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 18)

The control system according to Supplementary note 17, wherein the evaluation means evaluates the ease of excavation with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region.

According to the above configuration, by evaluating the ease of excavation with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 19)

The control system according to any one of Supplementary notes 16 to 18, wherein among a plurality of destination candidates, the specification means specifies, as the destination, a destination candidate for which a result of evaluation of the ease of excavation by the evaluation means is relatively low.

According to the above configuration, by moving the object to the destination that is specified on the basis of the result of evaluation, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 20)

The control system according to any one of Supplementary notes 15 to 19, wherein the destination of the object is a position at which the height of the object in the excavation target region is lower than at another position.

According to the above configuration, by specifying, as the destination, a position at which the height of the object in the excavation target region is lower than at another position, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 21)

The control system according to any one of Supplementary notes 15 to 20, further including a sensor that measures the information pertaining to the deposition state. According to the above configuration, by moving the object to the destination that is specified in accordance with the information pertaining to the deposition state, the information having been measured by the sensor, it is possible to form the object in a shape that allows the object to be easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 22)

The control system according to any one of Supplementary notes 15 to 213, wherein the excavation target region is a region in which the object is deposited and in which excavation is capable of being carried out.

The above configuration makes it possible to achieve higher work efficiency by making an object easily excavatable.

(Supplementary Note 23)

The control method according to Supplementary note 4, wherein the evaluation value concerning the average gradient of the height in the excavation range is an evaluation value that is configured to increase as a gradient value toward the excavator is greater.

According to the above configuration, by specifying the destination of the object with reference to the evaluation value that is configured to increase as a gradient value toward the excavator is greater, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 24)

The control method according to any one of Supplementary notes 1 to 6, wherein an origin of the object is a position at which the height of the object in the excavation target region is higher than at another position.

According to the above configuration, by specifying, as the origin, a position at which the height of the object in the excavation target region is higher than at another position, it is possible to form the object in a shape that allows the object to be more easily excavated, and to achieve higher excavation efficiency.

(Supplementary Note 25)

A non-transitory computer-readable storage medium storing therein a program for causing a computer to function as a control means that controls an excavator and as an acquisition means that acquires information pertaining to a deposition state of an object deposited; a specification means that specifies a destination of the object in an excavation target region with reference to the acquired information pertaining to the deposition state of the object; and an instruction means that instructs the excavator to move the object to the destination.

The above configuration brings about an effect similar to that brought about by Supplementary note 1.

(Supplementary Note 26)

A program for causing a computer to function as a control means that controls an excavator and as an acquisition means that acquires information pertaining to a deposition state of an object deposited; a specification means that specifies a destination of the object in an excavation target region with reference to the acquired information pertaining to the deposition state of the object; and an instruction means that instructs the excavator to move the object to the destination.

[Additional Remark 3]

The whole or part of the example embodiments disclosed above can also be expressed as follows.

A control apparatus including at least one processor, the at least one processor carrying out: an acquisition process for acquiring information pertaining to a deposition state of an object deposited; a specification process for specifying a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and an instruction process for instructing an excavator to move the object to the destination.

Note that the control apparatus may further include a memory, which may store a program for causing the at least one processor to carry out the acquisition process, the specification process, and the instruction process. The program may be stored in a non-transitory tangible computer-readable storage medium.

REFERENCE SIGNS LIST

• • 1, 3, 40, 40B Control apparatus
  • 2, 4, 5 Control system
  • 10, 21, 30, 41, 51 Acquisition section
  • 11, 22, 32, 43, 61 Specification section
  • 12, 23, 33, 44, 62 Instruction section
  • 46, 53, 63 Communication section
  • 47, 54, 64 Memory
  • 31, 42, 52 Evaluation section
  • 50 First control apparatus
  • 60 Second control apparatus
  • 100 Communication network
  • 200 Backhoe
  • 200a Bucket
  • 201 Controller
  • 202 Sensor
  • 300 Object
  • a21 Raking region
  • a22 Excavation target region
  • a23 Excavation range
  • P1 Turning center
  • p21 Excavation point
  • S1, S2 Control method

Claims

1. A control method comprising:

(a) acquiring information pertaining to a deposition state of an object deposited;

(b) specifying a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and

(c) instructing an excavator to move the object to the destination.

2. The control method according to claim 1, further comprising (d) evaluating ease of excavation of the object with reference to the information pertaining to the deposition state, wherein

in (b), the destination is specified with reference to the ease of excavation.

3. The control method according to claim 2, wherein

the information pertaining to the deposition state includes a height of the object and information pertaining to a gradient of the height of the object, and

in (d), the ease of excavation is evaluated with reference to the height of the object and the gradient of the height of the object.

4. The control method according to claim 3, wherein in (d), the ease of excavation is evaluated with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region.

5. The control method according to claim 2, wherein in (b), among a plurality of destination candidates, a destination candidate for which a result of evaluation of the ease of excavation in (d) is relatively low is specified as the destination.

6. The control method according to claim 1, wherein the destination of the object is a position at which the height of the object in the excavation target region is lower than at another position.

7. The control method according to claim 1, wherein the excavation target region is a region in which the object is deposited and in which excavation is capable of being carried out.

8. A control apparatus comprising at least one processor, the at least one processor carrying out:

an acquisition process for acquiring information pertaining to a deposition state of an object deposited;

a specification process for specifying a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and

an instruction process for instructing an excavator to move the object to the destination.

9. The control apparatus according to claim 8, wherein the at least one processor further carries out an evaluation process for evaluating ease of excavation of the object with reference to the information pertaining to the deposition state, and

in the specification process, the at least one processor specifies the destination with reference to the ease of excavation.

10. The control apparatus according to claim 9, wherein

the information pertaining to the deposition state includes a height of the object and information pertaining to a gradient of the height of the object, and

in the evaluation process, the at least one processor evaluates the ease of excavation with reference to the height of the object and the gradient of the height of the object.

11. The control apparatus according to claim 10, wherein in the evaluation process, the at least one processor evaluates the ease of excavation with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region.

12. The control apparatus according to claim 9, wherein in the specification process, among a plurality of destination candidates, the at least one processor specifies, as the destination, a destination candidate for which a result of evaluation of the ease of excavation in the evaluation process is relatively low.

13. The control apparatus according to claim 8, wherein the destination of the object is a position at which the height of the object in the excavation target region is lower than at another position.

14. The control apparatus according to claim 8, wherein the excavation target region is a region in which the object is deposited and in which excavation is capable of being carried out.

15. A control system comprising at least one processor, the at least one processor carrying out:

an acquisition process for acquiring information pertaining to a deposition state of an object deposited;

a specification process for specifying a destination of the object in an excavation target region, the destination being in accordance with the deposition state; and

an instruction process for instructing an excavator to move the object to the destination.

16. The control system according to claim 15, wherein the at least one processor further carries out an evaluation process for evaluating ease of excavation of the object with reference to the information pertaining to the deposition state, and

in the specification process, the at least one processor specifies the destination with reference to the ease of excavation.

17. The control system according to claim 16, wherein

the information pertaining to the deposition state includes a height of the object and information pertaining to a gradient of the height of the object, and

in the evaluation process, the at least one processor evaluates the ease of excavation with reference to the height of the object and the gradient of the height of the object.

18. The control system according to claim 17, wherein in the evaluation process, the at least one processor evaluates the ease of excavation with reference to an evaluation value concerning an average gradient of the height in an excavation range and an evaluation value concerning an average height at a far position in the excavation range and an average height in the excavation target region.

19. The control system according to claim 16, wherein in the specification process, among a plurality of destination candidates, the at least one processor specifies, as the destination, a destination candidate for which a result of evaluation of the ease of excavation in the evaluation process is relatively low.

20.-22. (canceled)

23. A non-transitory computer-readable storage medium storing therein a program for causing a computer to carry out the acquisition process, the specification process, and the instruction process according to claim 8.