Method and apparatus for control of hydraulic systems
An apparatus and method for controlling hydraulic systems. The control apparatus (module) accepts a variety of input forms, and the output is user-configurable to control both sides of an attached coil. The master module is programmable via a graphical user interface defining states and conditions triggering transitions between states. The master module may be combined with slave modules on a connection bus to control many subsystems. Reprogramming of the master module may occur in the field by use of flash memory, and input/output characteristics may be adjusted during operation of the system, allowing adjustment of systems exhibiting nonlinear response characteristics.
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The following invention relates generally to methods of and apparatus for controlling systems utilizing hydraulic power. More specifically, the instant invention relates to hydraulic control of multiple systems including resetting hydraulic parameters according to a flexible rule set.
BACKGROUND OF THE INVENTIONTypical systems under hydraulic control encompass a huge universe and include garbage trucks, nut harvesters, rock crushers, tub grinders, drilling machines, compactors, and grape harvesters. Control systems for hydraulic devices such as these have been developed and are currently in use. The major problem attending control of such devices is the lack of small-scale control of the systems. Large-scale control is simple: lifting, lowering, shaking, etc. Small-scale control can be analogized to fine motor control in humans, e.g., how much force to use when setting something down, or how much force to use when shaking fruit or nuts from a tree.
Lack of small-scale control results in damage: trees shaken too hard are uprooted; garbage cans set down too hard crack under the force; and workpieces are overground or overdrilled. Such damage can be avoided by the use of “smart” controllers: a controller that, for example, (1) picks up a receptacle, empties it, and, remembering where the ground is, sets it down without damaging it, or (2) harvests nuts by shaking the trees without damaging the tree. Unfortunately, smart controllers are rare, and, if unable to be modified subsequently, must of necessity define parameters based on extreme conditions, which is inefficient, since it can lead to oversizing, overpowering, or worse, inadequate performance.
SUMMARY OF THE INVENTIONThe present invention is characterized by its use of a master module having the ability to accept a variety of inputs and be programmed by a user to produce appropriate outputs. More specifically, the present invention includes a master control module that controls several subsystem devices. The master module may be located on a bus with other slave devices/modules, each controlled by the master module. Several slave devices/modules (e.g., input, output, network bridge, memory, etc.) may be controlled with one master module.
The master module accepts a variety of inputs, equipped with analog inputs, digital inputs, and universal inputs, which accept a variety of sensor devices. It has both on/off and proportional outputs, in which both the high and low sides of a connected coil may be controlled. LEDs indicate the state of each connection.
Programming takes place through a graphical user interface on a computer (or other input device). The program is in a visual format, allowing the user to specify several nodes through which the sequence travels and the transitional sequences that direct the path from one node to another. The input/output profile is depicted graphically, and the user may adjust the curve itself by adjusting the points on the curve. Adjustments may also be made while the controller is running. Thus, control of nonlinear response or of output having unknown characteristics may be achieved. Flash memory allows reprogramming in the field.
During operation, additional modules allow collection and storage of time-stamped (if desired) device data, which may be transferred to a PC for subsequent display, manipulation, and analysis. Other modules allow data transfer between devices that use different bus protocols and control of devices located on a bus utilizing a different protocol.
OBJECTS OF THE INVENTIONIt is a primary object of the present invention to provide a new and novel method and apparatus to allow “intelligent” configuration and control of hydraulic systems.
It is a further object of the present invention to provide a method and apparatus as characterized above utilizing a graphical user interface that may be programmed by a user without advanced knowledge of high-level programming languages, and thus avoids high outside programming costs.
It is a further object of the present invention to provide a method and apparatus as characterized above that provides for control of systems with nonlinear response characteristics in real time, while the system is in operation.
It is a further object of the present invention to provide a method and apparatus as characterized above that allows a user to control both high and low sides of an attached valve coil.
It is a further object of the present invention to provide a method and apparatus as characterized above that is versatile with respect to acceptable input forms.
It is a further object of the present invention to provide a method and apparatus as characterized above that indicates the state of the accompanying system via LED display.
It is a further object of the present invention to provide a method and apparatus as characterized above that collects and stores data from the active system for subsequent transfer to an external PC for manipulation and analysis.
It is a further object of the present invention to provide a method and apparatus as characterized above that may be integrated into a connection bus to control other modules according to the same programming.
It is a further object of the present invention to provide a method and apparatus as characterized above to provide a link that communicate with and capture data from devices located on a connection bus having a different bus protocol.
It is a further object of the present invention to provide a method and apparatus as characterized above to provide a link that allows control of a device located on a connection bus that utilizes a different bus protocol.
Viewed from a first vantage point, it is an object of the present invention to provide a system for control of and bidirectional communication between a central controller and a plurality of subsystems operatively dispersed on the system, comprising, in combination: each subsystem linked to both the controller and a work-performing device, having hydraulic fluid controlling operation of the device, the controller including means to modify operating criteria on each subsystem, the hydraulic fluid integrated in the system and distributed to each subsystem in accordance with the criteria as modified by the controller to effect change to the hydraulic fluid controlled device.
Viewed from a second vantage point, it is an object of the present invention to provide a method for programming logic sequences, the steps including: orienting a plurality of reference points in a graphical user interface; specifying a state for each reference point; designating one of the reference points as a starting point; and identifying conditions under which transition between reference points occurs, wherein the plurality of reference points and the conditions form a logic sequence depicted in the graphical user interface.
Viewed from a third vantage point, it is an object of the present invention to provide a system for creating a universal microprocessor-based control system for hydraulics, comprising, in combination: a master module having a plurality of inputs and outputs; a plurality of slave modules, wherein each slave module has a plurality of inputs and outputs; a connection bus interposed between the master module and the plurality of slave modules, the connection bus transmitting information therebetween; a work-performing device connected to at least one of the outputs on the master module or the slave module, wherein the work-performing device has hydraulic fluid controlling operation of the device.
Viewed from a fourth vantage point, it is an object of the present invention to provide a method for graphically defining and managing input/output functions for a controller, the steps including: connecting a controller and a work-performing device displaying output for the work-performing device as a function of input in a graphical format; specifying a plurality of movable points on the graphical format; and allowing control of nonlinear response of the work-performing device by the controller via movement of the plurality of movable points.
Viewed from a fifth vantage point, it is an object of the present invention to provide a control apparatus for hydraulic valve systems, comprising, in combination: analog input means; non-analog input means; and output means responsive to input received by the analog input means and the non-analog input means, wherein the analog input means and the non-analog input means share a common portal.
Viewed from a sixth vantage point, it is an object of the present invention to provide a control apparatus for hydraulic valve systems, comprising, in combination: input means having a single portal, wherein the input means are responsive to inputs comprising analog input and non-analog input; and output means responsive to t h e inputs received by the input means.
Viewed from a seventh vantage point, it is an object of the present invention to provide a control apparatus for control of hydraulic valves, comprising, in combination: input means, the input means programmable by a user; and output means responsive to the input means, wherein the output means include a coil having a high side and a low side and means for controlling both sides.
Viewed from a seventh vantage point, it is an object of the present invention to provide a module for linking a control system having a network which alters hydraulic means, comprising, in combination: network connection means; nonvolatile memory means communicating through the network communication means to store a plurality of data streams sent through the network connected through the network connection means; and output means to export stored data from the nonvolatile memory means.
Viewed from a eighth vantage point, it is an object of the present invention to provide a network bridge module for a hydraulic equipment control system which spans between first and second networks respectively having first and second protocols, comprising, in combination: a first network connection means; a second network connection means; and relay means, wherein the relay means allow communication between the first connection means connected to the first network and the second connection means connected to the second network, and wherein control messages sent over the first network to a device on the second network through the relay means effect control of the device on the second network.
Viewed from a ninth vantage point, it is an object of the present invention to provide a user-interface module for a hydraulic device control system, comprising in combination: network communication means, wherein the network communication means receives programming from an external source having an output, the output monitored by display means, wherein content of the display means is determined by programming received over a network through the network communication means; and input means feeding the network, the input means responsive to manual external input, wherein the manual external input is controlled from a series of choices contained on the display means.
Viewed from a tenth vantage point, it is an object of the present invention to provide a system for control of hydraulic devices, comprising in combination: a master module having inputs and outputs, the master module programmable by a user; and a plurality of slave modules, the plurality of slave modules chosen from the group consisting of: modules providing additional inputs; modules providing additional outputs; modules providing a user-interface into the system; modules providing nonvolatile memory storage; modules providing a network bridge between the system and a network utilizing a different protocol than the system; modules providing a display of system status; and modules providing a combination of additional inputs and additional outputs.
These and other objects will be made manifest when considering the following detailed specification when taken in conjunction with the appended drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
Considering the drawings, wherein like reference numerals denote like parts throughout the various drawing figures, reference numeral 10 is directed to the control system according to the present invention.
In its essence, the control system 10 is comprised of a master module 100 having multiple inputs 106, including analog, digital, and universal inputs. Universal inputs are programmable; they accept input from various types of sensors. Outputs 104 on the master module 100 include both on/off and proportional outputs. These outputs 104 allow a multitude of different output configurations to be programmed. LED indicator lights 110a-g on the master module 100 display the status of the various connections. The master module 100 may be used on its own or it may be combined with a plurality of slave modules 200a-h for control over a larger system (
Master module 100 is programmable by use of a graphical programming environment 150 (
One embodiment of the control system 10 is provided in
A second potential embodiment is shown in
Referring now to
Preferably, the power supply for the master module 100 operates over the full range of 8.5 Vdc to 32 Vdc and may be configured for high current applications. Output connections 104 for the master module 100 shown in
Input connections 106 for the master module 100 as shown include three analog/potentiometer inputs, eight digital (on/off) inputs, and three universal inputs. Each universal input may be programmed to accept analog voltage/current input, quadrature pulse input, counter pulse input, or RPM pulse input through the programming environment 150. Thus, any of several types of sensors may be connected to the master module 100.
The master module 100 connects to other devices (i.e., slave devices 200a-h) preferably via CAN bus connector 108a. An RS-232 port 108b allows connection to a PC on which the programming environment 150 is configured or to an external display.
Finally, a plurality of LEDs 110a-g are present on the master module 100. As shown, the master module 100 has a power LED 110a, a status LED 110b, eight digital input status LEDs 110c, six high-side output driver status LEDs 110d, three proportional output driver status LEDs 110e, and two CAN bus LEDs 110f,g. Each LED indicates status for its associated component (color descriptions are exemplary):
-
- Power LED 110a: Blinks if the power supply voltage is above +30 Vdc. Turns off if the power supply voltage drops below +8.0 Vdc.
- Status LED 110b: This LED is programmable and is commonly used for error status or blink codes.
- Digital Input Status 110c: Turns on when the corresponding input is activated. Inputs can be programmed as active high or low.
- High-Side Output Driver Status 110d: Turns on when the corresponding High-side output is activated. Blinks once per second for an open circuit. Blinks four times per second for a short circuit.
- Proportional Output Driver Status 110e: This LED displays minimum to maximum current status for the corresponding PWM output. The LED will display from red to green as the current changes from 0% to 100% (50% displaying yellow).
- CAN Bus LED: Module Status (MS) 110f:
- Off—There is no power applied to the module.
- On green—The module is operating in a normal condition.
- Flashing green—Device in standby state. May need commissioning.
- Flashing red—Recoverable Fault.
- On red—Module has an unrecoverable fault.
- Flashing Red/Green—Device is in self-test.
- CAN Bus LED: Network Status (NS) 110g:
- Off—Device is not on-line.
- Flashing green—Device on-line; no established connection to other nodes.
- On green—Device on-line; established connection to other nodes.
- Flashing red—One or more connections are in a timed-out state.
- On red—The device has detected an error rendering it incapable of communicating on the network.
As shown in
Aspects of the inputs 106 and outputs 104 are controlled in the programming environment 150 (
The output groups are similarly configured, shown in
Dither is a rapid, small movement of the spool about the desired shift point. It is intended to keep the spool moving to avoid stiction and average out hysterisis. Dither must be large and slow enough to make the spool move and small and fast enough not to cause pulsing or resonance in the system. The goal is to provide just enough dither to fix the problems without creating new ones.
Low-frequency pulse-width modulation (PWM) (typically less than 300 Hz) generates dither as a by-product of the PWM process. The amount of dither changes as the average coil current changes, reaching a maximum at 50% duty cyde. This may result in too much dither at some current levels and not enough at other levels. Different spools have different responses to the same dither current. Changing the PWM frequency will allow adjustment of the dither, but the amplitude and frequency of the dither cannot be independently adjusted. When the PWM frequency is high enough (typically above 5 kHz), the coil current will not have time to change significantly, and no byproduct dither is produced. Addition of dither during high-frequency PWM can thus be regulated, unlike during low-frequency PWM. The dither amplitude and frequency may be independently adjusted for maximum positive effect with minimal problems.
The programming environment 150 is used to program operations for the master module 100. The programming environment 150 utilizes a graphical interface and requires knowledge of the PC's operating system, light programming, and electro-hydraulics. At the outset, states 52 are entered, along with transitions 54 connecting the states 52, on the programming screen 50. Each transition 54 connects two states 52. States 52 are points in the program in which a particular logic sequence is repeated until a transition condition 56 is met. When the transition condition 56 is met, the program will change states 52. The states 52 and transitions 54 form a picture of the program that will be executed, shown in
The master module 100 may be used alone, or it may be used as in
To create a larger system, one may add a digital input module 200a, a high-side output module 200b, an analog input module 200e, or a universal I/O module 200g. One may also connect and communicate with additional master modules 100.
The digital input module 200a (
The high-side output module 200b (
The analog input module 200e (
The universal I/O module 200g (
An interface module 200c (
A memory module 200d (
A bridge module 200f (
An external display 200h may be connected directly to the base connection bus 202 to monitor the entire system.
The interface for the programming environment 150 allows easy addition of modules to the system (
Moreover, having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.
Claims
1. A system for control of and bidirectional communication between a central controller and a plurality of subsystems operatively dispersed on said system, comprising, in combination:
- each said subsystem linked to said controller, either directly or using communication bus means, and a work-performing device, having hydraulic fluid controlling operation of said device,
- said controller including means to modify operating criteria on said subsystem,
- said hydraulic fluid integrated in said system and distributed to each said subsystem in accordance with said criteria as modified by said controller to effect change to said hydraulic fluid controlled device.
2. The system of claim 1 wherein said central controller alters hydraulic fluid flow at each device via means for setting limits on each said subsystem to control fluid demand.
3. The system of claim 2 wherein said controller includes means to modify valve throughput at each said device.
4. A method for programming logic sequences, the steps including:
- orienting a plurality of reference points in a graphical user interface, said graphical user interface shown on a display;
- specifying a state for each of said plurality of reference points;
- designating one of said plurality of reference points as a starting point; and
- identifying conditions under which transition between reference points occurs, wherein said plurality of reference points and said conditions form a logic sequence depicted in said graphical user interface.
5. The method of claim 4 further including the steps of
- saving said logic sequence; and
- transferring said logic sequence to a controller, wherein said controller operates a work-performing device according to said logic sequence.
6. The method of claim 4 further including the steps of
- saving said logic sequence; and
- transferring said logic sequence to a fluidic circuit which operatively conditions a system formed from plural elements each influenced by said circuit.
7. A system for creating a universal microprocessor-based control system for hydraulics, comprising, in combination:
- a master module having a plurality of inputs and outputs;
- a plurality of slave modules, wherein each slave module has a plurality of inputs and outputs;
- a connection bus interposed between said master module and said plurality of slave modules, said connection bus transmitting information therebetween;
- a work-performing device connected to at least one of said outputs on said master module or said slave module, either directly or using communication bus means, wherein said work-performing device has hydraulic fluid controlling operation of said device.
8. (canceled)
9. A control apparatus for hydraulic valve systems, comprising, in combination:
- analog input means;
- non-analog input means; and
- output means responsive to input received by said analog input means and said non-analog input means, wherein said analog input means and said non-analog input means hare are received by a single common portal.
10. The apparatus of claim 9 wherein said input recognized by said non-analog input means comprises pulse inputs.
11. A control apparatus for hydraulic valve systems, comprising, in combination:
- input means having a single portal, wherein said input means are responsive to inputs comprising analog input and non-analog input; and
- output means responsive to said inputs received by said input means, whereby said single portal receives either analog input or non-analog input.
12. A control apparatus for control of hydraulic valves, comprising, in combination:
- input means, said input means programmable by a user; and
- output means responsive to said input means, wherein said output means includes a coil having a high side and a low side and means for controlling both said sides, said means for controlling both said sides including parameters for said high side and said low side, said parameters entered by a user.
13. The control apparatus of claim 12 wherein said output means produces either an output having a constant supply source voltage or a PWM output that sinks current to ground at a pulse-width-modulated frequency.
14. The control apparatus of claim 12 wherein said PWM output may be configured to a particular current range.
15. The control apparatus of claim 14 wherein said frequency is between 19 kHz and 20 kHz.
16. (canceled)
17. A module for linking a control system having a network which alters hydraulic means, comprising, in combination:
- network connection means, said network connection means receiving programming from an external source having an output, said programming allowing selection of data types to be collected;
- nonvolatile memory means communicating through said network communication means to store a plurality of data streams sent through the network connected through said network connection means, said data streams corresponding to said selection of data types and stored according to said programming; and
- output means to export stored data from said nonvolatile memory means.
18. The module of claim 17 further comprising clock means, said clock means supplementing said plurality of data streams with a time stamp.
19. The module of claim 18 wherein said nonvolatile memory means is divided into partitions to store said plurality of data streams simultaneously, each said data stream sequestered in a separate partition.
20. The module of claim 19 wherein any of said plurality of data streams comprises trend data, event data, fault data, or any combination thereof.
21. The module of claim 20 wherein any of said plurality of data streams comprises raw data.
22. The module of claim 21 wherein any of said plurality of data streams comprises data that has been manipulated or supplemented.
23. The module of claim 22 wherein said output means interface with an external data manipulation and/or viewing means.
24. A network bridge module for a hydraulic equipment control system which spans between first and second networks respectively having first and second protocols, comprising, in combination:
- a first network connection means;
- a second network connection means; and
- relay means, wherein said relay means allow communication between said first connection means connected to the first network and said second connection means connected to the second network, and wherein control messages sent over the first network to a device on the second network through said relay means effect control of the device on the second network, wherein said first and second protocols differ from one another.
25. The network bridge module of claim 24 wherein information from the device on the second network is collected by a device on the first network for use by the hydraulic equipment control system.
26. (canceled)
27. The control apparatus of claim 12 wherein said input means includes means having a single portal, wherein said input means are responsive to inputs comprising analog input and non-analog input.
28. The control apparatus of claim 27 wherein said output means produces either an output having a constant supply source voltage or a PWM output that sinks current to ground at a pulse-width-modulated frequency.
29. The control apparatus of claim 27 wherein said PWM output may be configured to a particular current range.
30. The control apparatus of claim 29 wherein said frequency is between 19 kHz and 20 kHz.
31. (canceled)
32. A system for control of hydraulic devices, comprising in combination:
- a master module having inputs and outputs, said master module programmable by a user; and
- a plurality of slave modules, said plurality of slave modules chosen from the group consisting of:
- modules providing additional inputs;
- modules providing additional outputs;
- modules providing a user-interface into said system;
- modules providing nonvolatile memory storage;
- modules providing a network bridge between said system and a network utilizing a different protocol than said system;
- modules providing a display of system status; and
- modules providing a combination of additional inputs and additional outputs,
- whereby the hydraulic devices are controlled by said master module in combination with said plurality of slave modules.
33. A control apparatus for control of hydraulic valves, comprising, in combination:
- input means, said input means programmable by a user; and
- output means responsive to said input means, wherein said output means includes a coil having a high side and a low side and means for controlling both said sides, and wherein said output means produces either an output having a constant supply source voltage or a PWM output that sinks current to ground at a pulse-width-modulated frequency, and wherein a dither frequency is superimposed on said frequency.
34. A control apparatus for control of hydraulic valves, comprising, in combination:
- input means, said input means programmable by a user, and said input means includes means having a single portal, wherein said input means are responsive to inputs comprising analog input and non-analog input; and
- output means responsive to said input means, wherein said output means includes a coil having a high side and a low side and means for controlling both said sides, and wherein said output means produces either an output having a constant supply source voltage or a PWM output that sinks current to ground at a pulse-width-modulated frequency, and wherein a dither frequency is superimposed on said frequency.
35. A system for controlling a plurality of hydraulic devices, comprising, in combination:
- a plurality of hydraulic devices; and
- a master controller connected to each said hydraulic device, either directly or using communication bus means, wherein said master controller is programmed to control aspects of each said hydraulic device and wherein said master controller includes means to re-program said master controller with respect to any of said plurality of hydraulic devices during use.
36. A control apparatus for control of hydraulic valves, comprising, in combination:
- input means; and
- output means responsive to said input means, said output means comprising output groups, said output groups having means for specifically controlling parameters about output from said output means.
37. The control apparatus of claim 36 further comprising means for controlling parameters about input received through said input means.
38. A method of programming logic sequences in a graphical user interface shown on a display, the steps including:
- defining at least two states, each said state represented by a graphical element; and
- specifying at least one transition between pairs of said at least two states, said transition represented as a connection between said states,
- whereby the graphically represented logic sequence forms a picture of a program to be executed.
39. The method of claim 38 further including the steps of:
- identifying transition conditions associated with each said transition; and
- labeling each said transition with an associated said transition condition.
40. The method of claim 39 further including the step of:
- labeling each said state with a caption.
41. The method of claim 40 further including the step of:
- indicating a starting point for the logic sequence in a graphical manner, said starting point represented in said caption.
42. A graphically formed logic programming sequence, comprising, in combination:
- at least two states, each said state represented by a singular element;
- a plurality of transitions, each said transition graphically connecting a pair of said states; and
- a plurality of transition conditions, each said transition associated with at least one said transition condition, each said transition condition adjacent to said associated transition.
Type: Application
Filed: Mar 2, 2005
Publication Date: Jul 7, 2005
Applicant:
Inventors: Rob Hulse (Nevada City, CA), Bruce Rasmus (Grass Valley, CA), Brian Tetzlaff (Santa Monica, CA)
Application Number: 11/071,430