A control method and system of an electro-hydraulic system of a rock drilling machine arm

Abstract

A kind of rock drilling mechanical arm electro-hydraulic system control method, comprising the following steps: establishing the action model of rock drilling mechanical arm, and determining the standard control parameter of electro-hydraulic system according to action model;Based on target control parameter received by main control module, and utilize target control parameter and closed loop feedback parameter to calculate fuzzy parameter;Fuzzy parameter is carried out fuzzy processing to obtain control variable;Control variable is carried out clear processing to obtain actual control parameter, and standard control parameter is corrected to obtain final control parameter using actual control parameter;Final control parameter is used to control electro-hydraulic system, and electro-hydraulic system is driven to act.The present application provides a kind of rock drilling mechanical arm electro-hydraulic system control method and system, generates fuzzy parameter based on target control parameter and closed loop feedback parameter, obtains accurate final control data by fuzzy control, so as to be able to control mechanical arm to reach target blasthole position accurately and smoothly, improve the positioning accuracy of rock drilling robot, and response speed is fast.

Description

Technical Field

[0001] This invention relates to the field of rock drilling robot technology, specifically to a rock drilling robotic arm electro-hydraulic system control method and system. Background Technology

[0002] A rock drilling robotic arm is a seven-degree-of-freedom articulated robotic arm primarily used to drive a drill rod at its end effector to create boreholes at target locations. Controlling the robotic arm to reach the target position involves the coordinated movement of its various telescopic and rotary joints; specifically, controlling the extension and retraction of each telescopic joint and the rotation of each rotary joint. These joint variations are controlled by the extension and retraction of the piston rods in the hydraulic cylinders within the joints. Because rock drilling robotic arms are heavy-duty industrial robotic arms, and their hydraulic drive system is extremely unstable and susceptible to various factors such as changes in the hydraulic oil medium, oil leaks in the hydraulic cylinders, and unstable operation of the relief valve, displacement deviations can occur during the movement of the hydraulic cylinder piston rods. Current technologies for controlling the voltage system of rock drilling robotic arms cannot effectively address this problem. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method and system for controlling an electro-hydraulic system of a rock drilling robot. Based on target control parameters and closed-loop feedback parameters, fuzzy parameters are generated, and precise final control data is obtained through fuzzy control. This enables the robot to accurately and smoothly reach the target borehole position, improving the positioning accuracy of the rock drilling robot and providing a fast response speed.

[0004] To achieve the above objectives, the specific solution adopted by the present invention is as follows: a control method for an electro-hydraulic system of a rock drilling robot arm, comprising the following steps: Establish a motion model for the rock drilling robot arm, and determine the standard control parameters of the electro-hydraulic system based on the motion model; Receive target control parameters and closed-loop feedback parameters of the electro-hydraulic system, and use the target control parameters and closed-loop feedback parameters to calculate fuzzy parameters; The control variables are obtained by performing fuzzy processing on the fuzzy parameters; The control variables are clarified to obtain the actual control parameters; The final control parameters are obtained by correcting the standard control parameters using the actual control parameters. The electro-hydraulic system is controlled using the final control parameters to drive its actions.

[0005] As a further optimization of the above-mentioned control method for the electro-hydraulic system of the rock drilling manipulator: the standard control parameters include proportional gain P, integral time constant I, and derivative time constant D; the fuzzy parameters include e, which characterizes the displacement deviation of the hydraulic cylinder in the electro-hydraulic system, and the rate of change of e ec; and the control variables include dynamic proportional gain, dynamic integral time constant, and dynamic derivative time constant.

[0006] As a further optimization of the above-mentioned control method for the electro-hydraulic system of the rock drilling robot arm, specific methods for obtaining control variables by fuzzy processing of fuzzy parameters include: Determine multiple first-standardized numerical intervals; Construct a two-dimensional fuzzy reference surface, and then represent the first standardized numerical interval in the fuzzy reference surface after fractalization; The fuzzy parameters are mapped onto the fuzzy reference surface, and the membership degree of the fuzzy parameters with respect to the first standardized numerical interval is calculated. The fuzzy parameters are adjusted based on their membership degree. The original variables are generated based on the adjusted fuzzy parameters; The original variables are standardized to obtain the control variables.

[0007] As a further optimization of the above-mentioned electro-hydraulic system control method for rock drilling robots, the methods for standardizing the original variables include: Determine multiple second-standardized numerical intervals; Construct multiple two-dimensional variable reference surfaces corresponding to the original variables; The second standardized numerical interval is then quantified and reflected in the variable reference plane; Map the original variables onto the variable reference plane and calculate the membership degree of the original variables with respect to the second standardized numerical interval; standardize the original variables to the second standardized numerical interval based on the membership degree of the original variables.

[0008] As a further optimization of the above-mentioned control method for the electro-hydraulic system of the rock drilling robot, the specific methods for obtaining control variables by fuzzy processing of fuzzy parameters also include: The standardized control variables are adjusted according to the time progression of controlling the electro-hydraulic system.

[0009] As a further optimization of the above-mentioned electro-hydraulic system control method for rock drilling robots, methods for adjusting the standardized control variables according to the time process include: In the early stage of the time process, increase the dynamic proportional gain, decrease the dynamic integral time constant, and increase the dynamic derivative time constant; in the middle stage of the time process, decrease the dynamic proportional gain, increase the dynamic integral time constant, and decrease the dynamic derivative time constant. In the later stages of the time process, increase the dynamic proportional gain, increase the dynamic integral time constant, and decrease the dynamic derivative time constant.

[0010] As a further optimization of the above-mentioned control method for the electro-hydraulic system of the rock drilling robot arm, the method for obtaining the actual control parameters by clarifying the control variables is as follows: In the formula, U O To clarify the actual control parameters, M i For membership degree, F i The value is in the fuzzy universe.

[0011] As a further optimization of the above-mentioned control method for the electro-hydraulic system of a rock drilling robot arm: a control system for the electro-hydraulic system of a rock drilling robot arm, based on the above control method, the system comprising: The main control module is used to build motion models and receive and transmit target control parameters; A fuzzy controller is used to perform fuzzy processing on fuzzy parameters to obtain control variables and generate final control parameters. The feedback module is used to collect closed-loop feedback parameters and transmit them to the main control module.

[0012] Beneficial effects: This invention generates fuzzy parameters based on target control parameters and closed-loop feedback parameters, and obtains accurate final control data through fuzzy control, thereby enabling the robotic arm to accurately and smoothly reach the target borehole position, improving the positioning accuracy of the rock drilling robot, and providing a fast response speed. Attached Figure Description

[0013] Figure 1 It is a block diagram of the control system;

[0014] Figure 2 This is a schematic diagram of the fuzzy reference surface corresponding to the displacement deviation e of the hydraulic cylinder;

[0015] Figure 3 This is a schematic diagram of the fuzzy reference surface corresponding to the rate of change ec of the hydraulic cylinder displacement deviation e;

[0016] Figure 4 It is ΔK P Schematic diagram of the corresponding fuzzy reference surface;

[0017] Figure 5 K I Schematic diagram of the corresponding fuzzy reference surface;

[0018] Figure 6 It is K D A schematic diagram of the corresponding fuzzy reference surface. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] A method for controlling the electro-hydraulic system of a rock drilling robot arm, comprising S1 to S6.

[0021] S1. Establish a motion model for the rock drilling robot arm and determine the standard control parameters of the electro-hydraulic system based on the motion model. The motion model for the rock drilling robot arm can adopt the method disclosed in Chinese patent document "CN113894790A"—a motion control method for a rock drilling robot arm based on end-effector posture constraints. By establishing geometrical mathematical models of two triangular hydraulic cylinders for the rock drilling robot arm, the functional relationships between the boom pitch and swing joints and the corresponding double-triangular hydraulic cylinder extension displacement functions, and the relationship between the beam swing joint and the corresponding single-triangular hydraulic cylinder extension displacement function, are found. This achieves the goal of obtaining real-time information on the extension displacement changes of the corresponding hydraulic cylinders from the real-time information of the joint angles. This is a disclosed prior art and will not be elaborated further here.

[0022] S2. Receive the target control parameters and the closed-loop feedback parameters of the electro-hydraulic system, and calculate the fuzzy parameters using the target control parameters and the closed-loop feedback parameters. The target control parameters are the parameters that need to be controlled by the electro-hydraulic system and can be generated by the host computer; the closed-loop feedback parameters are mainly the motion parameters of the rock drilling robot arm's end effector, including joint values ​​and other data, which can be acquired through the encoder built into the electro-hydraulic system.

[0023] In this embodiment, the standard control parameters include the proportional gain P, the integral time constant I, and the derivative time constant D. The fuzzy parameters include e, which characterizes the displacement deviation of the hydraulic cylinder in the electro-hydraulic system, and the rate of change of e ec. The control variables include the dynamic proportional gain, the dynamic integral time constant, and the dynamic derivative time constant. The selection of standard control parameters is a conventional design practice in the field of automation control technology and will not be elaborated further here. Based on the standard control parameters, the control variables should include K, which corresponds to the proportional gain P, the integral time constant I, and the derivative time constant D. P K I K D The three control variables are each initialized with a value K. P0 K I0 K D0 and variable ΔK P ΔK I ΔK D They are jointly obtained, and the specific relationship is as follows:

[0024] S3. Perform fuzzy processing on the fuzzy parameters to obtain the control variables. Specific methods include S31 to S36.

[0025] S31. Determine multiple first standardized numerical intervals. In this embodiment, seven first standardized numerical intervals are set for both e and ec, which are respectively represented as negative large (NB), negative medium (NM), negative small (NS), zero (ZO), positive small (PS), positive medium (PM), and positive large (PB).

[0026] S32. Construct a two-dimensional fuzzy reference surface, and represent the first standardized numerical intervals into the fuzzy reference surface after classification. During classification, different classification methods are determined according to different first standardized numerical intervals. Specifically, the NB interval corresponding to e uses a Gaussian plane, the PB interval uses an S-shaped plane, and the remaining intervals use triangular planes, which can overlap with each other. The resulting fuzzy reference surface can be as follows: Figure 2 As shown; the NB interval corresponding to ec uses a Z-shaped plane, the PB interval uses an S-shaped plane, and the remaining intervals use a triangular plane, which can intersect and overlap with each other. The resulting fuzzy reference surface can be as follows: Figure 3 As shown.

[0027] S33. Map the fuzzy parameters onto the fuzzy reference surface and calculate the membership degree of the fuzzy parameters with respect to the first standardized numerical interval. After determining the fuzzy reference surface, e and ec can be mapped onto the fuzzy reference surface, and the membership degree can be determined, i.e., which plane in the fuzzy reference surface the values ​​of e and ec lie in.

[0028] S34. Adjust the fuzzy parameters according to their membership degrees. Based on the membership degrees of the fuzzy parameters, the fuzzy parameters can be optimized to more accurately optimize the target control parameters. In this embodiment, the control range of the fuzzy parameters is finally determined to be [-3, 3].

[0029] S35. Generate the original variables based on the adjusted fuzzy parameters, i.e., generate K. P0 K I0 K D0 .

[0030] S36. Standardize the original variables to obtain control variables. Methods for standardizing the original variables include S361 to S365.

[0031] S361. Determine multiple second-standardized numerical intervals. The method for determining the second-standardized numerical intervals is the same as that for the first-standardized numerical intervals, namely negative large (NB), negative medium (NM), negative small (NS), zero (ZO), positive small (PS), positive medium (PM), and positive large (PB).

[0032] S362. Construct multiple two-dimensional variable reference surfaces corresponding to the original variables. The NB interval uses a Z-shaped plane, the PB interval uses an S-shaped plane, and the remaining membership function intervals all use triangular planes. The variable reference surfaces are as follows: Figure 4 , 5 As shown in Figure 6.

[0033] S363. The second standardized numerical interval is then represented in the variable reference plane.

[0034] S364. Map the original variables onto the variable reference plane and calculate the membership degree of the original variables with respect to the second standardized numerical interval.

[0035] S365. Standardize the original variables to the second standardized numerical range based on their membership degrees. In this embodiment, ΔK is... P ΔK I ΔK D Mapped onto the variable reference plane, and will determine ΔK. P The control range is [-3,3], ΔK I The control range is [-0.06, 0.06], ΔK D The control range is [-0.3, 0.3].

[0036] Subsequently, the standardized control variables are adjusted according to the time progression of controlling the electro-hydraulic system. Specifically, the adjustment methods for the standardized control variables based on the time progression include: in the early stage of the time progression, increasing the dynamic proportional gain, decreasing the dynamic integral time constant, and increasing the dynamic derivative time constant; in the middle stage of the time progression, decreasing the dynamic proportional gain, increasing the dynamic integral time constant, and decreasing the dynamic derivative time constant; and in the later stage of the time progression, increasing the dynamic proportional gain, increasing the dynamic integral time constant, and decreasing the dynamic derivative time constant. A detailed analysis follows.

[0037] Because K P The value of K determines the response speed of the electro-hydraulic system; as K increases... P The value of K can improve the response speed of the hydraulic cylinder and reduce the steady-state error of the entire electro-hydraulic system. However, an excessively large K... P A value of K will cause a large overshoot in the electro-hydraulic system, and vice versa. P A value that is too small will slow down the response speed of the electro-hydraulic system, resulting in an excessively long settling time. For the entire electro-hydraulic system, in the early stages of the time process, it is desirable to take a larger value for K initially when the electrical signal is received. P The value enables the hydraulic cylinder to respond quickly; in the middle of the time process, by reducing K... P The value maintains a stable speed for the hydraulic cylinder; in the later stages of the process, K is increased. PThis improves the tracking accuracy of the hydraulic cylinder.

[0038] In electro-hydraulic system control, K I Its main function is to eliminate the steady-state deviation of the entire electro-hydraulic system. Due to the numerous nonlinear factors in the electro-hydraulic system, integral action may lead to integral saturation in the initial stage of regulation, causing overshoot. Therefore, to prevent integral saturation in the early stages of the time process, K... I The effect should be reduced; in the middle of the time process, for the stability of the electro-hydraulic system, K I The effect of K should be moderate; in the later stages of the time process, in order to reduce static error, I Its role should be strengthened.

[0039] In electro-hydraulic systems, K D It regulates the dynamic characteristics of the system in the form of prediction. In the early stages of the time process, K should be increased. D This reduces the overshoot of the hydraulic system; in the middle of the time process, K should be appropriately reduced. D The effect remains constant over a period of time; later in the course of time, K... D The value should be reduced to avoid K. D The problem of excessively large values ​​causing excessively long adjustment times.

[0040] Based on the above analysis, adjusting the control variables according to the time process can ensure that the rock drilling robot can respond quickly and operate smoothly when finally controlled, thus achieving the effect of ensuring the control accuracy of the rock drilling robot.

[0041] S4. The control variables are then processed to obtain the actual control parameters. The method for obtaining the actual control parameters by processing the control variables is as follows: In the formula, U O To clarify the actual control parameters, M i For membership degree, F i The value is in the fuzzy universe.

[0042] S5. The standard control parameters are corrected using the actual control parameters to obtain the final control parameters. In the process of controlling an electro-hydraulic system, in addition to the core actual control parameters, there are other parameters that are related to the actual control parameters. Therefore, it is necessary to correct the standard control parameters using the actual control parameters. The specific content of the standard control parameters is conventional technology in this field and will not be elaborated here.

[0043] S6. Control the electro-hydraulic system using the final control parameters to drive its actions. Specifically, the final control parameters are input into the electro-hydraulic system's controller, which then controls the system's actions based on these parameters.

[0044] Please see Figure 2 A control system for an electro-hydraulic system of a rock drilling robot arm, based on the above-mentioned control method, includes a main control module, a fuzzy controller, and a feedback module.

[0045] The main control module is used to build motion models and receive and transmit target control parameters.

[0046] A fuzzy controller is used to process fuzzy parameters to obtain control variables and generate final control parameters. These final control parameters are then converted from digital signals to analog signals and input into the electro-hydraulic system to control its actions, thereby driving the rock drilling arm.

[0047] The feedback module is used to collect closed-loop feedback parameters and transmit them to the main control module. The feedback module may include an encoder, an angle / displacement converter, and an A / D converter for collecting motion data from the end effector of the rock drilling robot arm.

[0048] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling the electro-hydraulic system of a rock drilling robot arm, characterized in that, Includes the following steps: A motion model of the rock drilling robot arm is established, and the standard control parameters of the electro-hydraulic system are determined based on the motion model. The standard control parameters include proportional gain P, integral time constant I, and derivative time constant D. The fuzzy parameters include e, which characterizes the displacement deviation of the cylinder in the electro-hydraulic system, and the rate of change of e ec. The control variables include dynamic proportional gain, dynamic integral time constant, and dynamic derivative time constant. Receive target control parameters and closed-loop feedback parameters of the electro-hydraulic system, and use the target control parameters and closed-loop feedback parameters to calculate fuzzy parameters; The control variables are obtained by performing fuzzy processing on the fuzzy parameters; Specific methods for obtaining control variables by fuzzy processing of fuzzy parameters include: Determine multiple first-standardized numerical intervals; Construct a two-dimensional fuzzy reference surface, and then represent the first standardized numerical interval in the fuzzy reference surface after fractalization; The fuzzy parameters are mapped onto the fuzzy reference surface, and the membership degree of the fuzzy parameters with respect to the first standardized numerical interval is calculated. The fuzzy parameters are adjusted based on their membership degree. The original variables are generated based on the adjusted fuzzy parameters; Control variables are obtained by standardizing the original variables; methods for standardizing the original variables include: Determine multiple second-standardized numerical intervals; Construct multiple two-dimensional variable reference surfaces corresponding to the original variables; The second standardized numerical interval is then quantified and reflected in the variable reference plane; Map the original variables onto the variable reference plane and calculate the membership degree of the original variables with respect to the second standardized numerical interval; The original variables are standardized to the second standardized numerical range based on their membership degree. The standardized control variables are adjusted according to the time progression of the electro-hydraulic system control. Methods for adjusting standardized control variables based on the time progression include: In the early stages of the time process, increase the dynamic proportional gain, decrease the dynamic integral time constant, and increase the dynamic derivative time constant; In the middle of the time process, reduce the dynamic proportional gain, increase the dynamic integral time constant, and decrease the dynamic derivative time constant; In the later stages of the time process, increase the dynamic proportional gain, increase the dynamic integral time constant, and decrease the dynamic derivative time constant; The control variables are clarified to obtain the actual control parameters; The final control parameters are obtained by correcting the standard control parameters using the actual control parameters. The electro-hydraulic system is controlled using the final control parameters to drive its actions.

2. The electro-hydraulic system control method for a rock drilling robot arm as described in claim 1, characterized in that, The method for obtaining actual control parameters by clarifying control variables is as follows: ， In the formula, The actual control parameters after clarification. For membership degree, The value is in the fuzzy universe.

3. A control system for an electro-hydraulic system of a rock drilling robot arm, based on the control method as described in claim 1, characterized in that, The system includes: The main control module is used to build motion models and receive and transmit target control parameters; A fuzzy controller is used to perform fuzzy processing on fuzzy parameters to obtain control variables and generate final control parameters. The feedback module is used to collect closed-loop feedback parameters and transmit them to the main control module.

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