Excavator 3D integrated laser and radio positioning guidance system
An excavator 3D integrated laser and radio positioning guidance system (Ex_3D_ILRPGS) comprising: a mobile radio positioning system receiver configured to obtain 2D horizontal coordinates of the excavator, a bucket-to-machine-body positioning system configured to obtain coordinates of the boom, the stick and the bucket of the excavator, a laser detector configured to receive at least one laser beam and configured to provide a local vertical coordinate with a substantially high accuracy, and an on-board navigational system configured to receive and to integrate the 2D horizontal coordinates of the excavator obtained by the mobile radio positioning system receiver, the coordinates of the boom, the stick and the bucket of the excavator obtained by the bucket-to-machine-body positioning system, and the local vertical coordinate obtained by the laser detector, and configured to guide the cutting edge of the bucket of the excavator with substantially high vertical accuracy.
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The current invention relates to position tracking and machine control systems, and, more specifically, to a combination of laser systems and radio positioning systems configured to complement each other in order to optimize the tracking and machine control capabilities of prior art systems.
BACKGROUND ARTIn recent times there have been advances in the area of radio ranging or pseudolite machine control systems. However, the radio ranging or pseudolite machine control systems have limited, up to centimeter accuracy.
For example, Trimble introduced a family of machine control systems including the GCS300 with a single elevation control, the GCS400 having a dual elevation control, the GCS500 with a cross slope control, the GCS600 having a cross slope and elevation control, and finally, the GCS900 that provides a full 3D control up to centimeter accuracy. In another example, Trimble also introduced the SiteVision HEX machine control systems. Trimble's version 5.0 SiteVision System comprises a 3D machine guidance and control system for use on dozers, scrapers, motor graders, compactors, and excavators. The SiteVision HEX machine control systems use GPS technology. A GPS receiver installed on the dozer or grader continually computes the exact position of GPS antennas installed on each end of the machine's blade. An on-board computer determines the exact position of each blade tip and compares the positions to design elevation. It then computes the cut or fills to grade. This information is displayed on the in-cab screen, and the cut/fill data is passed to the SiteVision light bars, which guide the operator up or down for grade and right or left of a defined alignment.
In recent times there have been also advances in rotating laser systems including plane lasers and fan laser systems. Plane lasers provide a reference plane of light. Fan lasers provide one or more planes of light that are rotated about an axis, from which a difference in elevation can be derived. The common technique for deriving the difference in elevation is by determining the difference in time between detection of two or more fan beams. These systems, such as the Trimble Laser Station and Topcon Laser Zone systems provide accurate, up to millimeters differences in elevation. For excavators during a digging operation the critical accuracy is a vertical accuracy.
What is needed is to combine the radio-ranging systems with the laser-based systems to provide excavators with up to millimeters vertical accuracy.
DISCLOSURE OF THE INVENTIONThe present invention provides systems and methods for 3-D integrated laser and radio positioning and guidance of an excavator. The excavator comprises: a frame comprising a cab member horizontally pivoted about a tread member, a boom pivotally mounted at a proximal end to the cab by a first pivot means, a stick pivotally mounted at a proximal end to a distal end of the boom by a second pivot means, and a bucket pivotally mounted at a proximal end to a distal end of the stick by a third pivot means. A distal end of the bucket defines a cutting edge which is used to excavate dirt in response to movement of the bucket towards the frame.
One aspect of the present invention is directed to an excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS).
In one embodiment, the excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS) of the present invention comprises: a mobile radio positioning system receiver configured to obtain 2D horizontal coordinates of the excavator; a bucket-to-machine-body positioning system configured to determine the position coordinates of the boom, the stick and the bucket of the excavator relative to the machine body; a laser detector configured to receive at least one laser beam and configured to provide a local vertical coordinate with a substantially high accuracy; and an on-board navigational system configured to receive and to integrate the 2D horizontal coordinates of the excavator obtained by the mobile radio positioning system receiver, the position coordinates of the boom, the stick and the bucket of the excavator obtained by the bucket-to-machine-body positioning system, and the local vertical coordinate obtained by the laser detector, and configured to guide the cutting edge of the bucket of the excavator with substantially high vertical accuracy.
In one embodiment of the present invention, the mobile radio positioning system receiver is selected from the group consisting of: {an autonomous satellite receiver; a Virtual Reference Station (VRS)-based differential satellite positioning system receiver; a Wide Area Augmentation Service (WAAS)-based differential satellite positioning system receiver; a Real Time Kinematic (RTK)-based satellite positioning system receiver; an Omni STAR-High Performance (HP)-based differential satellite positioning system receiver; and a pseudolite receiver}.
In one embodiment of the present invention, the satellite receiver is selected from the group consisting of: {a Global Positioning System (GPS) receiver; a GLONASS receiver, a Global Navigation Satellite System (GNSS) receiver; and a combined GPS-GLONASS receiver}.
In one embodiment of the present invention, the bucket-to-machine-body positioning system is selected from the group consisting of: {an angle (tilt) sensor; an in-cylinder measurement sensor; a potentiometer sensor; and a cable encoder}.
In one embodiment of the present invention, the laser detector further comprises: a single slope planar laser detector configured to receive a single slope plane laser beam from a single slope plane laser transmitter.
In another embodiment of the present invention, the laser detector further comprises: a dual slope planar laser detector configured to receive a dual slope plane laser beam from a dual slope plane laser transmitter.
In an additional embodiment of the present invention, the laser detector further comprises: a single sloping fan laser detector configured to receive a single sloping fan laser beam from a single sloping fan laser transmitter.
Yet, in one more embodiment of the present invention, the laser detector further comprises: a fan laser detector configured to receive at least two fan laser beams from a fan laser transmitter. In this embodiment of the present invention, the on-board navigational system is configured to compute the difference in height between the fan laser transmitter and the fan laser detector to increase the vertical accuracy of the Ex—3D_ILRPGS system.
In one embodiment of the present invention, the on-board navigational system further comprises: an on-board computer configured to calculate the difference between an actual position of the cutting edge of the bucket and a design surface, and configured to control the position of the cutting edge of the bucket by controlling hydraulics valves configured to operate the cutting edge of the bucket.
In one embodiment, the excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS) of the present invention further comprises: an on-board display system configured to display the movement of the bucket of the excavator, wherein a vertical coordinate of the cutting edge of the bucket is displayed with an accuracy substantially similar to a vertical accuracy of the laser beam.
In one embodiment, the excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS) of the present invention further comprises: a remotely located control station configured to remotely operate the excavator, and a communication link configured to link the remotely located control station and the on-board navigational system of the Ex—3D_ILRPGS system. In this embodiment of the present invention, the on-board navigational system is configured to transmit an excavator real time positioning data to the remotely located control station via the communication link, and the on-board navigational system is configured to receive at least one control signal from the remotely located control station via the communication link. The wireless communication link is selected from the group consisting of: {a cellular link; a radio; a private radio band; a SiteNet 900 private radio network; a wireless Internet; a satellite wireless communication link; and an optical wireless link}.
In this embodiment of the present invention, the remotely located control station further comprises: a display configured to display movements of the bucket of the remotely controlled excavator.
Another aspect of the present invention is directed to a method of operating an excavator with substantially high vertical accuracy by using an Ex—3D_ILRPGS system.
In one embodiment, the method of the present invention comprises: (A) obtaining 2D horizontal coordinates of the excavator by using the mobile radio positioning system receiver; (B) determining the position coordinates of the boom, the stick and the bucket of the excavator relative to the machine body by using the bucket-to-machine-body positioning system; (C) obtaining a local vertical coordinate with a substantially high accuracy by using the laser detector configured to receive at least one laser beam from a laser transmitter; (D) receiving and integrating the 2D horizontal coordinates of the excavator obtained by the mobile radio positioning system receiver, the position coordinates of the boom, the stick and the bucket of the excavator obtained by the bucket-to-machine-body positioning system, and the local vertical coordinate obtained by the laser detector by using the on-board navigational system; and (E) guiding the cutting edge of the bucket of the excavator with substantially high vertical accuracy by using the on-board navigational system.
In one embodiment of the present invention, the step (A) further comprises: (A1) selecting the mobile radio positioning system receiver from the group consisting of: {an autonomous satellite receiver; a Virtual Reference Station (VRS)-based differential satellite positioning system receiver; a Wide Area Augmentation Service (WAAS)-based differential satellite positioning system; receiver a Real Time Kinematic (RTK)-based satellite positioning system receiver; an Omni STAR-High Performance (HP)-based differential satellite positioning system receiver; and a pseudolite receiver}. In this embodiment of the present invention, the step (A) further comprises: (A2) selecting the satellite receiver from the group consisting of: {a Global Positioning System (GPS) receiver; a GLONASS receiver, a Global Navigation Satellite System (GNSS) receiver; and a combined GPS-GLONASS receiver}.
In one embodiment of the present invention, wherein the mobile radio positioning system receiver further comprises a satellite receiver and a pseudolite receiver; the step (A) further comprises: obtaining a first horizontal coordinate of the excavator by using the satellite receiver, and obtaining a second horizontal coordinate of the excavator by using the pseudolite receiver.
In one embodiment of the present invention, the step (B) further comprises: (B1) selecting at least one position sensor from the group consisting of: {a tilt sensor; an in-cylinder measurement sensor; a potentiometer; and a cable encoder}.
In one embodiment of the present invention, the step (C) further comprises: (C1) receiving a single slope plane laser beam from a single slope plane laser transmitter by using a single slope planar laser detector. In another embodiment of the present invention, the step (C) further comprises: (C2) receiving a dual slope plane laser beam from a dual slope plane laser transmitter by using a dual slope planar laser detector. In one more embodiment of the present invention, the step (C) further comprises: (C3) receiving a single sloping fan laser beam from a single sloping fan laser transmitter by using a single sloping fan laser detector. Yet, in an additional embodiment of the present invention, the step (C) further comprises: (C4) receiving at least two fan laser beams from a fan laser transmitter by using a fan laser detector; wherein the on-board navigational system is configured to compute the difference in height between the fan laser transmitter and the fan laser detector to increase the vertical accuracy of the Ex—3D_ILRPGS system.
In one embodiment of the present invention, the step (D) further comprises: (D1) using an on-board computer to calculate the difference between an actual position of the cutting edge of the bucket and a design surface.
In one embodiment of the present invention, the step (E) further comprises: (E1) using the on-board navigational system to control the position of the cutting edge of the bucket by controlling hydraulics valves configured to operate the cutting edge of the bucket. In another embodiment of the present invention, the step (E) further comprises: (E2) using a remotely located control station to remotely operate the excavator. In one more embodiment of the present invention, the step (E) further comprises: (E3) using a communication link to connect the remotely located control station and the on-board navigational system of the Ex—3D_ILRPGS system; (E4) transmitting an excavator real time positioning data to the remotely located control station via the communication link; and (E5) receiving at least one control signal from the remotely located control station via the communication link. In this embodiment of the present invention, the step (E3) further comprises: (E3, 1) selecting the wireless communication link from the group consisting of: {a cellular link; a radio; a private radio band; a SiteNet 900 private radio network; a wireless Internet; a satellite wireless communication link; and an optical wireless link}.
In one embodiment, wherein the excavator further includes an on-board display system, the method of the present invention further comprises: (F) displaying the movement of the bucket of the excavator by using an on-board display system, wherein a vertical coordinate of a cutting edge of the bucket is displayed with accuracy substantially similar to a vertical accuracy of the laser beam.
In one embodiment, wherein the remotely located control station further includes a display system, the method of the present invention further comprises: (H) displaying the movement of the bucket of the excavator by using the control station display system, wherein a vertical coordinate of a cutting edge of the bucket is displayed with an accuracy substantially similar to a vertical accuracy of the laser beam.
One more aspect of the present invention is directed to a method of operating an excavator with improved vertical accuracy by using the Ex—3D_ILRPGS system, wherein 3D coordinates of the excavator are obtained by using a mobile radio positioning system receiver; and wherein a local vertical coordinate is obtained with a substantially high accuracy by using a laser detector configured to receive at least one laser beam from a laser transmitter.
In one embodiment, the method of the present invention comprises: (A) obtaining 3D coordinates of the excavator by using the mobile radio positioning system receiver; (B) determining the position coordinates of the boom, the stick and the bucket of the excavator relative to the machine body by using the bucket-to-machine-body positioning system; (C) obtaining a local vertical coordinate with a substantially high accuracy by using the laser detector configured to receive at least one laser beam from a laser transmitter; (D) receiving and integrating 3D coordinates of the excavator obtained by the mobile radio positioning system receiver, the position coordinates of the boom, the stick and the bucket of the excavator relative to the machine body obtained by the bucket-to-machine-body positioning system, and the local vertical coordinate obtained by the laser detector by using an on-board navigational system in order to improve vertical accuracy of the mobile radio positioning system receiver; and (E) guiding the cutting edge of the bucket of the excavator with improved vertical accuracy by using the on-board navigational system.
Yet, one more aspect of the present invention is directed to a method of operating an excavator with improved vertical accuracy by using the Ex—3D_ILRPGS system and by assigning weight functions to different measurements.
In one embodiment of the present invention, the method comprises: (A) obtaining a set of 3D coordinates measurements of the excavator by making a plurality measurements by using the mobile radio positioning system receiver; (B) obtaining position coordinates of the boom, the stick and the bucket of the excavator by utilizing the bucket-to-machine-body positioning system; (C) obtaining a set of local vertical coordinate measurements with a substantially high accuracy by making a plurality measurements by using the laser detector configured to receive at least one laser beam from a laser transmitter; (D) selecting a weight function configured to assign a 3D weight function to the set of 3D measurements obtained by using the mobile radio positioning system receiver, and configured to assign a vertical weight function to the set of local vertical coordinate measurements obtained by using the laser detector; (E) integrating the set of 3D coordinates measurements of the excavator with 3D weight function, and the set of the local vertical coordinate measurements with the vertical weight function by using the on-board navigational system in order to improve vertical accuracy of the mobile radio positioning system receiver; and (F) guiding the cutting edge of the bucket of the excavator with improved vertical accuracy by using the on-board navigational system.
The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
Reference now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific-details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present invention.
Some portions of the detailed descriptions which follow are presented in terms of a mobile radio positioning system receiver, a laser-based positioning system, and an on-board navigational system. These descriptions and representations are the means used by those skilled in the navigational system arts to most effectively convey the substance of their work to others skilled in the art.
In one embodiment of the present invention,
In one embodiment of the present invention, the excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS) 10 further comprises: the mobile radio positioning system receiver 12 configured to obtain 2D horizontal coordinates of the excavator 14, and the bucket-to-machine-body positioning system 16 configured to determine the position of the bucket cutting edge 30 relative to the machine body 33.
Referring still to
In one embodiment of the present invention, the satellite receiver (not shown) is selected from the group consisting of: {a Global Positioning System (GPS) receiver; a GLONASS receiver, a Global Navigation Satellite System (GNSS) receiver; and a combined GPS-GLONASS receiver}.
The Global Positioning System (GPS) is a system of satellite signal transmitters that transmits information from which an observer's present location and/or the time of observation can be determined. The GPS system is fully described in the document ICD-GPS-200: GPS Interface Control Document, ARINC Research, 1997, GPS Joint Program Office, which is incorporated by reference herein.
Another satellite-based navigation system is called the Global Orbiting Navigational System (GLONASS), which can operate as an alternative or supplemental system. The GLONASS system was placed in orbit by the former Soviet Union and now maintained by the Russian Republic.
As disclosed in the European Commission “White Paper on European transport policy for 2010”, the European Union will develop an independent satellite navigation system GALILEO as a part of a global navigation satellite infrastructure (GNSS).
Reference to a radio positioning system (RADPS) herein refers to a Global Positioning System (GPS), to a Global Orbiting Navigation System (GLONASS), to GALILEO System, and to any other compatible Global Navigational Satellite System (GNSS) satellite-based system that provides information by which an observer's position and the time of observation can be determined, all of which meet the requirements of the present invention, and to a ground based radio positioning system such as a system comprising of one or more pseudolite transmitters.
After the RADPS receiver determines the coordinates of i-th satellite by demodulating the transmitted ephemeris parameters, the RADPS receiver can obtain the solution of the set of the simultaneous equations for its unknown coordinates (x0, y0, z0) and for unknown time bias error (cb). The RADPS receiver can also determine velocity of a moving platform.
Referring still to
In one embodiment, the mobile radio positioning system receiver 12 (of
The differential GPS receiver can obtain the differential corrections from different sources. Referring still to
The fixed Base Station (BS) placed at a known location determines the range and range-rate measurement errors in each received GPS signal and communicates these measurement errors as corrections to be applied by local users. The Base Station (BS) has its own imprecise clock with the clock bias CB
Referring still to
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Indeed, the Virtual Base Station (VBS) is configured to deliver a network-created correction data to a multiplicity of rovers via a concatenated communications link consisting of a single cellular connection, and a radio transmission or broadcasting system. The location of the radio transmitting system can be co-located with a GPS Base Station designated as the position of the local Virtual Reference Station. This GPS Base Station determines its position using GPS, and transmits its location to the VRS Base Station via a cellular link between the local GPS Base Station and the VRS Base Station. It enables the VRS Base Station to generate differential corrections as if such differential corrections were actually being generated at the real GPS Base Station location. An article “Long-Range RTK Positioning Using Virtual Reference Stations,” by Ulrich Vollath, Alois Deking, Herbert Landau, and Christian Pagels, describing VRS in more details, is incorporated herein as a reference in its entirety, and can be accessed at the following URL: http://trl.trimble.com/dscgi/ds.py/Get/File-93152/KIS2001-Paper-LongRange.pdf.
Referring still to
The Omni STAR-HP (High Performance) solution is a dual frequency GPS augmentation service that provides robust and reliable high performance GPS positioning. By using dual frequency GPS observations, Omni STAR-HP can measure the true ionospheric error at the reference station and user location, substantially eliminating this effect in positioning accuracy. Using these iono-free measurements with other information contained in the GPS receiver carrier phase data, the OmniSTAR-HP solution is able to create a wide area positioning solution of unmatched accuracy and performance in selected areas. Published accuracies are 0.2 meter horizontal (Hz) and 0.3 meter vertical (Z).
Referring still to
Referring still to
The following discussion is focused on a GPS receiver, though the same approach can be used for a GLONASS receiver, for a GPS/GLONASS combined receiver, GALILEO receiver, or any other RADPS receiver.
Referring still to
In one embodiment of the present invention, the bucket-to-machine-body positioning system 16 is configured to determine the position of the bucket cutting edge 30 relative to the machine body 33 by using the tilt (angle) sensor 18 attached to the boom 36, the tilt (angle) sensor 20 attached to the stick 38, and the tilt (angle) sensor 22 attached to the bucket 40.
A tilt sensor manufactured by SignalQuest, Inc., located in Lebanon, N.H., 03766, USA, can be used for the purposes of the present invention. SignalQuest, Inc. manufactures embedded micro-sensors. For instance, the SQ-SEN-001P series sensors produce continuous on-off contact closures when in motion. When at rest, it will either settle in an open or closed state. It is sensitive to both tilt (static acceleration) and vibration (dynamic acceleration). The sensor can be easily used to produce a series of CMOS or TTL level logic pulses using a single resistor to limit current. This signal can be used to interrupt (wake up) a microcontroller or can be counted to estimate the amount and duration of activity. The sensor is fully passive, requires no signal conditioning, and can be easily used in a microcontroller interrupt circuit that draws 0.25 uA of continuous current. Another sensor manufactured by SignalQuest, Inc. is the SQ-SI-360DA Solid-State MEMS Inclinometer. SQ-SI-360DA Solid-State MEMS Inclinometer provides both an analog voltage output and digital serial output corresponding directly to a full-scale range of 360εc of pitch angle or +80εc of pitch and roll angle.
In one embodiment of the present invention, the bucket-to-machine-body positioning system 16 is configured to determine the position of the bucket cutting edge 30 relative to the machine body 33 by using cable encoders (not shown) that measure the extension of the hydraulic rams. Trimble Navigation LTD manufactures CE21 that uses cable encoders.
A cable encoder for the purposes of the present invention can be implemented by using an optical incremental encoder. Optical incremental encoder is a linear/angular position sensor that uses light and optics to sense motion. Optical encoders can provide position information at high speeds. Most rotary optical encoders consist of a glass disk with equally spaced markings, a light source mounted on one side of the disk, and a photo detector mounted on the other side. The components of rotary optical encoders are typically packaged in a rugged enclosed housing protecting the light path and electronics from dust and other materials frequently present in hostile industrial environments. When the disk rotates, the markings on the disk temporarily obscure the passage of light causing the encoder to output a pulse. The number of pulses generated by the encoder per revolution dictates the resolution of the encoder. The resolution of encoders (their PPR, pulses per revolution), typically ranges from a few PPR to as high as a few hundred thousand PPR. Because the markings on the disk are uniformly distributed, encoders always generate a pulse in response to a known incremental move in position. Subsequently, the position of an object can be measured by connecting the output of an encoder to a counter that increments or decrements every time the encoder generates a pulse. The value of the counter indicates the position of the object quantized to the resolution of the encoder. That is, if an encoder generates 10 pulses per revolution, the resolution of the position measurement can be no better than 1/10 th of a revolution.
To detect the direction of motion and increase the effective resolution of the encoder, a second photo detector is added and a mask is inserted between the glass disk and the photo detectors (not illustrated). The two photo detectors and the mask are arranged so that two sine waves (which are out of phase by 90°) are generated as the encoder shaft is rotated. These quadrature signals as they are called are either sent out of the encoder directly as analog sine wave signals or squared using comparators to produce digital outputs. To increase the resolution of the encoder, a method called interpolation is applied to either or both the sine wave or square wave outputs. Interpolation typically results in an increased encoder resolution of 2 to 25 times the fundamental resolution of the glass disk. Direction is derived by simply looking at the timing of the quadrature signals from the encoder.
A variation on the standard rotary encoder is the hollow shaft encoder. Hollow shaft encoders are self contained encoders without a shaft. Instead of coupling to a shaft to measure position, hollow shaft encoders simply mount over the shaft to be measured. Subsequently, hollow shaft encoders eliminate the resonance associated with couplings and simplify the difficulties of alignment. Linear optical encoders sense linear motion. Linear encoders replace the rotating disk with a stationary scale marked at equally spaced intervals. The scale of a linear encoder can be constructed from glass, metal or tape (metal, plastic . . . ). The markings on the scale are read with a moving head assembly that contains the light source and photo detectors. The resolution of a linear encoder is specified in units of distance and is dictated by the distance between markings. Linear encoders are available in lengths from several centimeters to hundreds of meters and resolutions as low as a micron (or less).
The laser optical encoder is another type of motion sensor. Although these devices use a different measurement approach internally, they offer the same functionality as standard encoders. Of the variety of motion sensors available, encoders provide the best accuracy and speed for a reasonable price and are readily available from numerous manufacturers.
In one embodiment of the present invention, the bucket-to-machine-body positioning system 16 is configured to determine the position of the bucket cutting edge 30 relative to the machine body 33 by using the position sensing cylinders (in-cylinder measurement) where the length of the cylinder is determined by using methods like time of flight or other methods to measure the distance from one end of the cylinder to the other.
In one embodiment of the present invention, the bucket-to-machine-body positioning system 16 is configured to determine the position of the bucket cutting edge 30 relative to the machine body 33 by using a potentiometer which is a type of bridge circuit for measuring voltages. The original potentiometers are divided into four main classes: the constant resistance potentiometer, the constant current potentiometer, the microvolt potentiometer and the thermocouple potentiometer.
There are also systems in development that use a mix, for example a potentiometer on the boom, a tilt sensor on the stick (with integrated laser detector) and a position sensing cylinder on the bucket. Manufacturers of “bucket to machine body” sub systems include Mikrofyn, Prolec, Axiomatic and Trimble.
Referring still to
More specifically, according to the U.S. Pat. No. 6,433,866, the laser transmitter 50 (of
In another embodiment of the present invention, referring still to
In one embodiment of the present invention,
Referring still to
In one embodiment of the present invention, the on-board navigational system (28 of
In one embodiment, the excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS) of the present invention further comprises: an on-board display system (29 of
In one embodiment, the excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS) of the present invention further comprises: a remotely located control station (60 of
In one embodiment of the present invention, referring still to
In one embodiment of the present invention, the wireless communication link (62 of
In one embodiment of the present invention, the wireless communication link (62 of
In one additional embodiment, the wireless communication link (62 of
The wireless communication link (62 of
In one embodiment of the present invention, a cellular telephone communication means can be used to get a wireless access to the Internet in order, for example, to broadcast the real time coordinates of the self-surveying laser transmitter position on a special web-site.
The wireless communication device (63 of
In one embodiment of the present invention, the wireless communication device (63 of
Another aspect of the present invention is directed to a method of operating an excavator with substantially high vertical accuracy. The method of the present invention can be performed by using the excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS) 10 of
In one embodiment, the method of the present invention comprises (not shown): (A) obtaining 2D horizontal coordinates of the excavator by using the mobile radio positioning system receiver (12 of
In one embodiment of the present invention, the step (A) further comprises (not shown, please see discussion above): (Al) selecting the mobile radio positioning system receiver (12 of
In one embodiment of the present invention, wherein the mobile radio positioning system receiver (12 of
In one embodiment of the present invention, the step (B) further comprises: (B1) selecting the bucket-to-machine-body positioning system (16 of
In one embodiment of the present invention, more specifically, the step (C) of obtaining the local vertical coordinate with substantially high accuracy further comprises: (C1) receiving the single slope plane laser beam (26 of
In one embodiment of the present invention, more specifically, the step (C) of obtaining the local vertical coordinate with substantially high accuracy further comprises: (C2) receiving the dual slope plane laser beam (not shown) from the dual slope plane laser transmitter (50 of
In one embodiment of the present invention, more specifically, the step (C) of obtaining the local vertical coordinate with substantially high accuracy further comprises: (C3) receiving the single sloping fan laser beam (76 of
In one embodiment of the present invention, more specifically, the step (C) of obtaining the local vertical coordinate with substantially high accuracy further comprises: (C4) receiving at least two fan laser beams (74 and 76 of
In one embodiment of the present invention, the step (D) of receiving and integrating the 2D horizontal coordinates of the excavator obtained by the mobile radio positioning system receiver, the position coordinates of the boom, the stick and the bucket of the excavator obtained by the bucket-to-machine-body positioning system, and the local vertical coordinate obtained by the laser detector further comprises: (D1) using the on-board computer (not shown) to calculate the difference between an actual position of the cutting edge of the bucket (30 of
In one embodiment of the present invention, the step (E) of guiding the cutting edge of the bucket of the excavator with substantially high vertical accuracy further comprises: (El) using the on-board navigational system (28 of
In one embodiment of the present invention, the step (E) of guiding the cutting edge (30 of
In one embodiment, wherein the excavator further includes the on-board display system (29 of
In one embodiment, wherein the remotely located control station (60 of
One more aspect of the present invention is directed to a method of operating an excavator with improved vertical accuracy by using the Ex—3D_ILRPGS system, wherein 3D coordinates of the excavator are obtained by using a mobile radio positioning system receiver; and wherein a local vertical coordinate is obtained with a substantially high accuracy by using a laser detector configured to receive at least one laser beam from a laser transmitter.
In one embodiment of the present invention, the method comprises (not shown): (A) obtaining 3D coordinates of the excavator by using the mobile radio positioning system receiver; (B) obtaining position coordinates of the boom, the stick and the bucket of the excavator by utilizing the bucket-to-machine-body positioning system; (C) obtaining a local vertical coordinate with a substantially high accuracy by using the laser detector configured to receive at least one laser beam from a laser transmitter; (D) receiving and integrating the 3D coordinates of the excavator obtained by the mobile radio positioning system receiver, the coordinates of the boom, the stick and the bucket of the excavator obtained by the bucket-to-machine-body positioning system, and the local vertical coordinate obtained by the laser detector by using an on-board navigational system in order to improve vertical accuracy of the mobile radio positioning system receiver; and (E) guiding the cutting edge of the bucket of the excavator with improved vertical accuracy by using the on-board navigational system.
Yet, one more aspect of the present invention is directed to a method of operating an excavator with improved vertical accuracy by using the Ex—3D_ILRPGS system and by assigning weight functions to different measurements.
A weight function is a mathematical device used when performing a sum, integral, or average in order to give some elements more of a “weight” than others. They occur frequently in statistics and analysis, and are closely related to the concept of a measure. Weight functions can be constructed in both discrete and continuous settings.
In the discrete setting, a weight function w: A→ is a positive function defined on a discrete set A, which is typically finite or countable. The weight function w(a):=1 corresponds to the unweighted situation in which all elements have equal weight. One can then apply this weight to various concepts.
If
f: A→
is a real-valued function, then the unweighted sum of f on A is
but for a weight function
w: A→,
the weighted sum is
One common application of weighted sums arises in numerical integration.
If B is a finite subset of A, one can replace the unweighted cardinality |B| of B by the weighted cardinality
If A is a finite non-empty set, one can replace the unweighted mean or average
by the weighted mean or weighted average
In this case only the relative weights are relevant. Weighted means are commonly used in statistics to compensate for the presence of bias.
The terminology weight function arises from mechanics: if one has a collection of n objects on a lever, with weights
w1, . . . wn
(where weight is now interpreted in the physical sense) and locations
x1, . . . xn,
then the lever will be in balance if the fulcrum of the lever is at the center of mass
which is also the weighted average of the positions xi.
In one embodiment, the method of the present invention comprises: (A) obtaining a set of 3D coordinates measurements of the excavator by making a plurality measurements by using the mobile radio positioning-system receiver; (B) obtaining position coordinates of the boom, the stick and the bucket of the excavator by utilizing the bucket-to-machine-body positioning system; (C) obtaining a set of local vertical coordinate measurements with a substantially high accuracy by making a plurality measurements by using the laser detector configured to receive at least one laser beam from a laser transmitter; (D) selecting a weight function configured to assign a 3D weight function to a set of 3D measurements obtained by using the mobile radio positioning system receiver, and configured to assign a vertical weight function to a set of local vertical coordinate measurements obtained by using the laser detector; (E) integrating the set of 3D coordinates measurements of the excavator with the 3D weight function, and the set of the local vertical coordinate measurements with the vertical weight function by using the on-board navigational system in order to improve vertical accuracy of the mobile radio positioning system receiver; and (F) guiding the cutting edge of the bucket of the excavator with improved vertical accuracy by using the on-board navigational system.
EXAMPLES1) Benching on a point of known height and then catching the beam to get a known height on the beam for both flat surface and sloping surfaces.
2) Stopping in the beam and averaging a number of GPS positions with reference to the beam to get an elevation on the beam (or elevation and orientation on a sloping beam)
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents
Claims
1. An excavator 3D integrated laser and radio positioning guidance system (Ex—3D_ILRPGS); wherein an excavator further comprises: a frame comprising a cab member horizontally pivoted about a tread member; a boom pivotally mounted at a proximal end to said cab by a first pivot means; a stick pivotally mounted at a proximal end to a distal end of said boom by a second pivot means; and a bucket pivotally mounted at a proximal end to a distal end of said stick by a third pivot means; wherein a distal end of said bucket defines a cutting edge which is used to excavate dirt in response to movement of said bucket towards said frame; said Ex—3D_ILRPGS comprising:
- a mobile radio positioning system receiver configured to obtain 2D horizontal coordinates of said excavator;
- a bucket-to-machine-body positioning system configured to obtain position coordinates of said boom, said stick and said bucket of said excavator;
- a laser detector configured to receive at least one laser beam and configured to provide a local vertical coordinate with a substantially high accuracy; and
- an on-board navigational system configured to receive and to integrate said 2D horizontal coordinates of said excavator obtained by said mobile radio positioning system receiver, said position coordinates of said boom, said stick and said bucket of said excavator obtained by said bucket-to-machine-body positioning system, and said local vertical coordinate obtained by said laser detector, and configured to guide said cutting edge of said bucket of said excavator with substantially high vertical accuracy.
2. The system of claim 1, wherein said mobile radio positioning system receiver is selected from the group consisting of: {an autonomous satellite receiver; a Virtual Reference Station (VRS)-based differential satellite positioning system receiver; a Wide Area Augmentation Service (WAAS)-based differential satellite positioning system receiver; a Real Time Kinematic (RTK)-based satellite positioning system receiver; an Omni STAR-High Performance (HP)-based differential satellite positioning system receiver; and a pseudolite receiver}; and wherein said satellite receiver is selected from the group consisting of: {a Global Positioning System (GPS) receiver; a GLONASS receiver, a Global Navigation Satellite System (GNSS) receiver; and a combined GPS-GLONASS receiver}.
3. The system of claim 1, wherein said bucket-to-machine-body positioning system is selected from the group consisting of: {a tilt sensor; an in-cylinder measurement sensor; a potentiometer; and a cable encoder}.
4. The system of claim 1, wherein said laser detector further comprises:
- a single slope planar laser detector configured to receive a single flat plane laser beam from a single flat plane laser transmitter.
5. The system of claim 1, wherein said laser detector further comprises:
- a single slope planar laser detector configured to receive a single sloping plane laser beam from a single sloping plane laser transmitter.
6. The system of claim 1, wherein said laser detector further comprises:
- a dual slope planar laser detector configured to receive a dual slope plane laser beam from a dual slope plane laser transmitter.
7. The system of claim 1, wherein said laser detector further comprises:
- a single sloping fan laser detector configured to receive a single sloping fan laser beam from a single sloping fan laser transmitter, wherein said on-board navigational system is configured to compute the difference in height between said fan laser transmitter and said fan laser detector to increase the vertical accuracy of said Ex—3D_ILRPGS system.
8. The system of claim 1, wherein said laser detector further comprises:
- a fan laser detector configured to receive at least two fan laser beams from a fan laser transmitter; wherein said on-board navigational system is configured to compute the difference in height between said fan laser transmitter and said fan laser detector to increase the vertical accuracy of said Ex—3D_ILRPGS system.
9. The system of claim 1 further comprising:
- an on-board display system configured to display the movement of said bucket of said excavator, wherein a vertical coordinate of a cutting edge of said bucket is displayed with accuracy substantially similar to a vertical accuracy of said laser beam.
10. The system of claim 9, wherein said on-board navigational system further comprises:
- an on-board computer configured to calculate the difference between an actual position of said cutting edge of said bucket and a design surface, and wherein said on-board display system is configured to display said actual position of said cutting edge of said bucket relative to said design surface.
11. The system of claim 1, wherein said on-board navigational system further comprises:
- an on-board computer configured to calculate the difference between an actual position of said cutting edge of said bucket and a design surface, and configured to control said position of said cutting edge of said bucket by controlling hydraulics valves configured to operate said cutting edge of said bucket.
12. The system of claim 1 further comprising:
- a remotely located control station configured to remotely operate said excavator; and
- a communication link configured to link said remotely located control station and said on-board navigational system of said Ex—3D_ILRPGS system;
- wherein said on-board navigational system is configured to transmit an excavator real time positioning data to said remotely located control station via said communication link, and wherein said on-board navigational system is configured to receive at least one control signal from said remotely located control station via said communication link; and wherein said wireless communication link is selected from the group consisting of: {a cellular link; a radio; a private radio band; a SiteNet 900 private radio network; a wireless Internet; a satellite wireless communication link; and an optical wireless link}.
13. The system of claim 11, wherein said remotely located control station further comprises:
- a display configured to display said remotely controlled excavator.
14. A method of operating an excavator with substantially high vertical accuracy by using an Ex—3D_ILRPGS system; wherein said excavator further comprises: a frame comprising a cab member horizontally pivoted about a tread member; a boom pivotally mounted at a proximal end to said cab by a first pivot means; a stick pivotally mounted at a proximal end to a distal end of said boom by a second pivot means; and a bucket pivotally mounted at a proximal end to a distal end of said stick by a third pivot means; wherein a distal end of said bucket defines a cutting edge which is used to excavate dirt in response to movement of said bucket towards said frame; said Ex—3D_ILRPGS system comprising: a mobile radio positioning system receiver, a bucket-to-machine-body positioning system, a laser detector, and an on-board navigational system; said method comprising:
- (A) obtaining 2D horizontal coordinates of said excavator by using said mobile radio positioning system receiver;
- (B) obtaining position coordinates of said boom, said stick and said bucket of said excavator by utilizing said bucket-to-machine-body positioning system;
- (C) obtaining a local vertical coordinate with a substantially high accuracy by using said laser detector configured to receive at least one laser beam from a laser transmitter;
- (D) receiving and integrating said 2D horizontal coordinates of said excavator obtained by said mobile radio positioning system receiver, said position coordinates of said boom, said stick and said bucket of said excavator obtained by said bucket-to-machine-body positioning system, and said local vertical coordinate obtained by said laser detector by using said on-board navigational system; and
- (E) guiding said cutting edge of said bucket of said excavator with substantially high vertical accuracy by using said on-board navigational system.
15. The method of claim 14, wherein said step (A) of obtaining 2D horizontal coordinates of said excavator by using said mobile radio positioning system receiver further comprises:
- (A1) selecting said mobile radio positioning system receiver from the group consisting of: {an autonomous satellite receiver; a Virtual Reference Station (VRS)-based differential satellite positioning system receiver; a Wide Area Augmentation Service (WAAS)-based differential satellite positioning system receiver; a Real Time Kinematic (RTK)-based satellite positioning system receiver; an Omni STAR-High Performance (HP)-based differential satellite positioning system receiver; and a pseudolite receiver}; and
- (A2) selecting said satellite receiver from the group consisting of: {a Global Positioning System (GPS) receiver; a GLONASS receiver, a Global Navigation Satellite System (GNSS) receiver; and a combined GPS-GLONASS receiver}.
16. The method of claim 14, wherein said mobile radio positioning system receiver further comprises a satellite receiver and a pseudolite receiver; wherein said satellite receiver is configured to obtain a first horizontal coordinate of said excavator; and wherein said pseudolite receiver is configured to obtain a second horizontal coordinate of said excavator; and wherein said step (A) of obtaining 2D horizontal coordinates of said excavator by using said mobile radio positioning system receiver further comprises:
- (A3) selecting said mobile radio positioning system receiver from the group consisting of: {an autonomous satellite receiver; a Virtual Reference Station (VRS)-based differential satellite positioning system receiver; a Wide Area Augmentation Service (WAAS)-based differential satellite positioning system receiver; a Real Time Kinematic (RTK)-based satellite positioning system receiver; and an Omni STAR-High Performance (HP)-based differential satellite positioning system receiver}; and
- (A4) selecting said satellite receiver from the group consisting of: {a Global Positioning System (GPS) receiver; a GLONASS receiver, a Global Navigation Satellite System (GNSS) receiver; and a combined GPS-GLONASS receiver}.
17. The method of claim 14, wherein said step (B) further comprises:
- (B1) selecting said bucket-to-machine-body positioning system from the group consisting of: {a tilt sensor; an in-cylinder measurement sensor; a potentiometer; and a cable encoder}.
18. The method of claim 14, wherein said step (C) of obtaining said local vertical coordinate with said substantially high accuracy further comprises:
- (C1) receiving a single slope plane laser beam from a single slope plane laser transmitter by using a single slope planar laser detector.
19. The method of claim 14, wherein said step (C) of obtaining said local vertical coordinate with said substantially high accuracy further comprises:
- (C2) receiving a dual slope plane laser beam from a dual slope plane laser transmitter by using a dual slope planar laser detector.
20. The method of claim 14, wherein said step (C) of obtaining said local vertical coordinate with said substantially high accuracy further comprises:
- (C3) receiving a single sloping fan laser beam from a single sloping fan laser transmitter by using a single sloping fan laser detector.
21. The method of claim 14, wherein said step (C) of obtaining said local vertical coordinate with said substantially high accuracy further comprises:
- (C4) receiving at least two fan laser beams from a fan laser transmitter by using a fan laser detector; wherein said on-board navigational system is configured to compute the difference in height between said fan laser transmitter and said fan laser detector to increase the vertical accuracy of said Ex—3D_ILRPGS system.
22. The method of claim 14, wherein said step (D) further comprises:
- (D1) using an on-board computer to calculate the difference between an actual position of said cutting edge of said bucket and a design surface.
23. The method of claim 14, wherein said step (E) of guiding said cutting edge of said bucket of said excavator with substantially high vertical accuracy further comprises:
- (E1) using said on-board navigational system to control said position of said cutting edge of said bucket by controlling hydraulics valves configured to operate said cutting edge of said bucket.
24. The method of claim 14, wherein said step (E) of guiding said cutting edge of said bucket of said excavator with substantially high vertical accuracy further comprises:
- (E2) using a remotely located control station to remotely operate said excavator.
25. The method of claim 14, wherein said step (E) of guiding said cutting edge of said bucket of said excavator with substantially high vertical accuracy further comprises:
- (E3) using a communication link to link said remotely located control station and said on-board navigational system of said Ex—3D_ILRPGS system;
- (E4) transmitting an excavator real time positioning data to said remotely located control station via said communication link; and
- (E5) receiving at least one control signal from said remotely located control station via said communication link.
26. The method of claim 25, wherein said step (E3) further comprises:
- (E3, 1) selecting said wireless communication link from the group consisting of: {a cellular link; a radio; a private radio band; a SiteNet 900 private radio network; a wireless Internet; a satellite wireless communication link; and an optical wireless link}.
27. The method of claim 14 further comprising:
- (F) displaying the movement of said bucket of said excavator by using an on-board display system, wherein a vertical coordinate of a cutting edge of said bucket is displayed with accuracy substantially similar to a vertical accuracy of said laser beam.
28. The method of claim 14 further comprising:
- (H) displaying the movement of the bucket of the excavator by using a control station display system, wherein a vertical coordinate of a cutting edge of said bucket is displayed with accuracy substantially similar to a vertical accuracy of said laser beam.
29. A method of operating an excavator with improved vertical accuracy by using an Ex—3D_ILRPGS system; wherein said excavator further comprises: a frame comprising a cab member horizontally pivoted about a tread member; a boom pivotally mounted at a proximal end to said cab by a first pivot means; a stick pivotally mounted at a proximal end to a distal end of said boom by a second pivot means; and a bucket pivotally mounted at a proximal end to a distal end of said stick by a third pivot means; wherein a distal end of said bucket defines a cutting edge which is used to excavate dirt in response to movement of said bucket towards said frame; said Ex—3D_ILRPGS system comprising: a mobile radio positioning system receiver, a bucket-to-machine-body positioning system, a laser detector, and an on-board navigational system; wherein 3D coordinates of said excavator are obtained by using said mobile radio positioning system receiver; and wherein a local vertical coordinate is obtained with a substantially high accuracy by using said laser detector configured to receive at least one laser beam from a laser transmitter; said method comprising:
- (A) obtaining 3D coordinates of said excavator by using said mobile radio positioning system receiver;
- (B) obtaining position coordinates of said boom, said stick and said bucket of said excavator by utilizing said bucket-to-machine-body positioning system;
- (C) obtaining a local vertical coordinate with a substantially high accuracy by using said laser detector configured to receive at least one laser beam from a laser transmitter;
- (D) receiving and integrating said 3D coordinates of said excavator obtained by said mobile radio positioning system receiver, said coordinates of said boom, said stick and said bucket of said excavator obtained by said bucket-to-machine-body positioning system, and said local vertical coordinate obtained by said laser detector by using an on-board navigational system in order to improve vertical accuracy of said mobile radio positioning system receiver; and
- (E) guiding said cutting edge of said bucket of said excavator with improved vertical accuracy by using said on-board navigational system.
30. The method of claim 29, wherein said mobile radio positioning system receiver further comprises a satellite receiver and a pseudolite receiver; wherein said satellite receiver is configured to obtain at least one coordinate of said excavator; and wherein said pseudolite receiver is configured to obtain at least one coordinate of said excavator; and wherein said mobile radio positioning system receiver is configured to obtain 3D coordinates of said excavator; and wherein said step (A) of obtaining 3D coordinates of said excavator by using said mobile radio positioning system receiver further comprises:
- (A1) selecting said mobile radio positioning system receiver from the group consisting of: {an autonomous satellite receiver; a Virtual Reference Station (VRS)-based differential satellite positioning system receiver; a Wide Area Augmentation Service (WAAS)-based differential satellite positioning system receiver; a Real Time Kinematic (RTK)-based satellite positioning system receiver; and an Omni STAR-High Performance (HP)-based differential satellite positioning system receiver}; and
- (A2) selecting said satellite receiver from the group consisting of: {a Global Positioning System (GPS) receiver; a GLONASS receiver, a Global Navigation Satellite System (GNSS) receiver; and a combined GPS-GLONASS receiver}.
31. A method of operating an excavator with improved vertical accuracy by using an Ex—3D_ILRPGS system and by assigning weight functions to different measurements; wherein said excavator further comprises: a frame comprising a cab member horizontally pivoted about a tread member; a boom pivotally mounted at a proximal end to said cab by a first pivot means; a stick pivotally mounted at a proximal end to a distal end of said boom by a second pivot means; and a bucket pivotally mounted at a proximal end to a distal end of said stick by a third pivot means; wherein a distal end of said bucket defines a cutting edge which is used to excavate dirt in response to movement of said bucket towards said frame; said Ex—3D_ILRPGS system comprising: a mobile radio positioning system receiver, a bucket-to-machine-body positioning system, a laser detector, and an on-board navigational system; said method comprising:
- (A) obtaining a set of 3D coordinates measurements of said excavator by making a plurality of measurements by using said mobile radio positioning system receiver;
- (B) obtaining position coordinates of said boom, said stick and said bucket of said excavator by utilizing said bucket-to-machine-body positioning system;
- (C) obtaining a set of local vertical coordinate measurements with a substantially high accuracy by making a plurality measurements by using said laser detector configured to receive at least one laser beam from a laser transmitter;
- (D) selecting a weight function configured to assign a 3D weight function to said set of 3D measurements obtained by using said mobile radio positioning system receiver, and configured to assign a vertical weight function to said set of local vertical coordinate measurements obtained by using said laser detector;
- (E) integrating said set of 3D coordinates measurements of said excavator with said 3D weight function, and said set of the local vertical coordinate measurements with said vertical weight function by using said on-board navigational system in order to improve vertical accuracy of said mobile radio positioning system receiver; and
- (F) guiding said cutting edge of said bucket of said excavator with improved vertical accuracy by using said on-board navigational system.
Type: Application
Filed: Aug 24, 2006
Publication Date: Feb 28, 2008
Applicant:
Inventor: Mark E. Nichols (Christchurch)
Application Number: 11/509,995
International Classification: E02F 5/02 (20060101);