A shotcrete mechanical arm, control system and control method

Abstract

The present application relates to the technical field of engineering machinery, and discloses a spraying mechanical arm, a control system and a control method, which are used for wet spraying engineering vehicles for concrete in tunnels. The end of the mechanical arm is connected to a spray gun, and includes a telescopic arm, a large arm and a small arm connected in sequence; one end of the telescopic arm is installed on the body of the engineering vehicle; one end of the large arm is connected to the other end of the telescopic arm through a first rotary joint; the other end of the large arm is connected to one end of the small arm through a second rotary joint; the spray gun is connected to the small arm through a third rotary joint; and also includes a first inclination sensor respectively arranged on the large arm and a second inclination sensor arranged on the small arm, the measuring axis of the first inclination sensor is parallel to the rotation axis of the first rotary joint and is in the same direction, and the measuring axis of the second inclination sensor is parallel to the rotation axis of the second rotary joint and is in the same direction. The mechanical arm structure of the present invention can achieve the maximum decoupling between the movement of each joint and the position and posture of the spray head, and the structure is simple and easy to implement.

Description

Technical Field

[0001] The present invention belongs to the technical field of engineering machinery, and in particular relates to a spraying mechanical arm, a control system and a control method. Background Art

[0002] Concrete spraying is widely used in mining and transportation tunnel construction. Traditional spraying technology often uses a remote control to control the movement of a robotic arm to complete the horizontal or vertical linear movement of the spray gun, and sprays the concrete while the robotic arm moves horizontally and vertically. However, this method has too high technical requirements for the operator and the control accuracy is too low, so it is necessary to realize the automatic movement of the spray gun in the horizontal or vertical direction.

[0003] According to the spraying trajectory of the spraying manipulator, the existing technical solutions generally divide the structure of the manipulator into three parts: vertical motion mechanism, horizontal motion mechanism and spray gun circle drawing mechanism. The lifting of the upper arm and the leveling of the telescopic arm constitute the vertical motion trajectory of the spraying manipulator. The operator controls the movement of the oil cylinder piston of the lifting of the upper arm and the leveling of the telescopic arm through the handle to make the spray gun complete the vertical movement; the telescopic movement of the telescopic arm constitutes the horizontal motion trajectory of the spraying manipulator; the spray circle drawing mechanism constitutes the spray circle drawing trajectory of the spraying manipulator. The relationship between the movement of each joint of the traditional structure of the manipulator and the posture of the nozzle is coupled, which makes the operation difficult. Several joints need to be adjusted at the same time to complete the change of posture according to the expected path.

[0004] Since shotcrete manipulators generally use hydraulically driven joints, the valve-controlled hydraulic system controls the displacement, speed and force of the load, and the hydraulic system often uses a high-precision position sensor to measure the position. However, in actual applications, installing a position sensor in a proportional valve-controlled cylinder will make the system complex, and reduce reliability and efficiency. Summary of the invention

[0005] The present invention provides a shotcrete robot arm to solve at least one of the above technical problems.

[0006] The technical solution adopted by the present invention is:

[0007] The present invention provides a spraying mechanical arm, which is used for a wet spraying engineering vehicle for concrete in a tunnel, wherein the end of the mechanical arm is connected with a spray gun, and comprises a telescopic arm, a large arm, and a small arm which are connected in sequence;

[0008] One end of the telescopic arm is mounted on the body of the engineering vehicle;

[0009] One end of the upper arm is connected to the other end of the telescopic arm via a first swivel joint;

[0010] The other end of the upper arm is connected to one end of the lower arm via a second swivel joint;

[0011] The spray gun is connected to the forearm via a third swivel joint;

[0012] It also includes a first inclination sensor respectively arranged on the upper arm and a second inclination sensor respectively arranged on the lower arm, the measuring axis of the first inclination sensor is parallel to and in the same direction as the rotation axis of the first swivel joint, and the measuring axis of the second inclination sensor is parallel to and in the same direction as the rotation axis of the second swivel joint.

[0013] As a preferred embodiment of the present invention, the rotation axes of the first swivel joint, the second swivel joint and the third swivel joint are all parallel to the extension direction of the telescopic arm.

[0014] As a preferred embodiment of the present invention, a swing link and a fourth swing joint are further provided between the spray gun and the third swing joint, one end of the swing link is connected to the third swing joint, and the other end is connected to the fourth swing joint, the spray gun is connected to the swing link via the fourth swing joint, and the rotation axis of the fourth swing joint is in the vertical direction.

[0015] As a preferred embodiment of the present invention, it also includes a third inclination sensor installed on the connecting rod between the third swivel joint and the spray gun, and the measuring axis of the third inclination sensor is parallel to the rotation axis of the third swivel joint and is in the same direction.

[0016] As a preferred embodiment of the present invention, a fifth swivel joint is provided between the telescopic arm and the body of the engineering vehicle, and a rotation axis of the fifth swivel joint is along a vertical direction.

[0017] The present invention also provides a shotcrete mechanical arm control system for controlling the aforementioned shotcrete mechanical arm, comprising a remote controller, a controller and an actuator;

[0018] The remote controller is used to send the movement speed of the end of the robotic arm in the horizontal direction and the vertical direction to the controller;

[0019] The controller is used to receive the motion speed data of the remote controller and the measured values ​​of the first inclination sensor, the second inclination sensor and the third inclination sensor, and can convert the motion speed data to obtain the corresponding target joint angle, and output a control signal according to the error between each target joint angle and the corresponding measured value of the first inclination sensor, the second inclination sensor and the third inclination sensor and the error conversion rate;

[0020] The actuator is used to drive the first rotary joint, the second rotary joint and the third rotary joint to move to a target joint angle according to a control signal output by the controller.

[0021] The present invention also provides a method for controlling the posture of a shotcrete robot arm, using the aforementioned shotcrete robot arm control system, characterized in that it includes:

[0022] S1: Establishing a tunnel coordinate system OXYZ, adjusting the extension direction of the telescopic arm along the OX direction, wherein the OX direction represents a direction parallel to the tunnel surface to be sprayed; the OY direction represents a direction perpendicular to the surface to be sprayed; and the OZ direction represents a direction perpendicular to the ground;

[0023] S2: Determine the period t of the controller executing the control program, and send the movement speed v of the end of the robot arm in the OY direction to the controller through the remote controller. y and the velocity v in the OZ direction z ;

[0024] S3: The movement speed v of the end of the robot arm y 、v z Converted into the position of the end of the small arm relative to the front end of the large arm in the OY direction and the OZ direction at time t;

[0025] S4: obtaining a target rotation angle α of the first rotary joint and a target rotation angle β of the second rotary joint according to the position of the end of the forearm relative to the front end of the upper arm in the OY direction and the OZ direction;

[0026] S5: The target rotation angles α and β of the first rotary joint and the second rotary joint are respectively compared with the measured values ​​jd of the first inclination sensor and the second inclination sensor. 1′ and jd 2′ Perform position closed-loop control to make the boom and forearm reach the target position;

[0027] S6: According to the measurement value jd of the third inclination sensor 3’ Determine the angle between the spray gun and the surface to be sprayed, and adjust the third swivel joint to make the spray gun perpendicular to the surface to be sprayed.

[0028] As a preferred embodiment of the present invention, in step S4, the formula for calculating the target rotation angle α of the first rotary joint and the target rotation angle β of the second rotary joint is:

[0029] At time t, the position of the end of the forearm relative to the front end of the upper arm in the OXYZ coordinate system is:

[0030] Z t =Z0+v z t;

[0031] Y t =Y0+v y t;

[0032] Where: Zt , Y t They respectively represent the distances of the end of the forearm relative to the front end of the large arm on the Y axis and the Z axis in the OXYZ coordinate system at time t, Z0 and Y0 are initial values, and t represents time;

[0033] By geometric method, we can get:

[0034] d1 sinα-d2 sinβ=Z t ;

[0035] d1 cosα+d2 cosβ=Y t ;

[0036] Where: d1 is the length of the upper arm, d2 is the length of the lower arm;

[0037] When you need to change the distance between the spray gun and the surface to be sprayed, use v z =0, v y ≠0; when the height of the spray gun relative to the ground needs to be changed, v z ≠0, v y =0;

[0038] Solving the above equations together, we get:

[0039] When Z t ≥0,

[0040] α=cos -1 (s-D1-D2) / (2*d1*d2)-cos -1 (s-D1+D2) / (2*d2*S)+cos -1 (Y t / S);

[0041] β=cos -1 (s-D1+D2) / (2*d2*S)-cos -1 (Y t / S);

[0042] When Z t <0,

[0043] α=cos -1 (s-D1-D2) / (2*d1*d2)-cos -1 (s-D1+D2) / (2*d2*S)-cos -1 (Y t / S);

[0044] β=cos -1 (s-D1+D2) / (2*d2*S)+cos -1 (Y t / S);

[0045] Where D1 = d1 2 ; D2 = d2 2 ; s = Z t 2 +Y t 2 ;

[0046] As a preferred embodiment of the present invention, in step S5, the target angles jd1 and jd2 of the first inclination sensor and the second inclination sensor are calculated according to the target rotation angle α of the first swivel joint and the target rotation angle β of the second swivel joint, and the target angles jd1 and jd2 of the first inclination sensor and the second inclination sensor are compared with the current measurement value jd 1’ and jd 2’ The error between the first and second inclination sensors is compensated for by an error angle to perform position closed-loop control; if the current measured values ​​jd 1’ and jd 2’ equal to the target angles jd1 and jd2, the upper arm and the lower arm reach the target position; if the current measured values ​​jd of the first inclination sensor and the second inclination sensor are 1’ and jd 2’ If the target angles jd1 and jd2 are not equal, the error angle compensation will continue until the current measured value jd 1’ and jd 2’ Equal to the target angles jd1 and jd2.

[0047] Due to the adoption of the above technical solution, the beneficial effects achieved by the present invention are as follows:

[0048] 1. The present invention changes the structure of the mechanical arm to achieve maximum decoupling of the joint movements, making the operation simpler and clearer, and reducing the technical requirements for the operator. Specifically, the telescopic arm is installed on the body of the engineering vehicle, and the telescopic arm moves forward and backward in a direction parallel to the surfaces to be sprayed on both sides of the tunnel. The first swivel joint and the second swivel joint can be driven by hydraulic swivel to make the upper arm and the lower arm rotate around the rotation axis of the first swivel joint and the second swivel joint respectively, thereby controlling the vertical distance between the spray gun and the surface to be sprayed and the vertical height between the spray gun and the ground. The third swivel joint is used to drive the spray gun to rotate until it is perpendicular to the surface to be sprayed to prevent the spray slurry from rebounding.

[0049] The first inclination sensor and the second inclination sensor can be used to measure the angles of the upper arm and the lower arm that cannot be decoupled. Specifically, the corresponding angle is obtained according to the relative positions of the first swivel joint and the second swivel joint in the vehicle coordinate system, and a position closed loop is formed with the measurement values ​​of the first inclination sensor and the second inclination sensor to control the movement of the spray gun in the horizontal or vertical direction. At the same time, the third inclination sensor on the nozzle is used to automatically maintain the nozzle posture angle, thereby achieving the maximum decoupling between the movement of each joint and the position and posture of the nozzle. At the same time, the structure is simple and easy to implement.

[0050] 2. The control system of the entire shotcrete robot arm sends the movement speed of the end of the robot arm in the horizontal or vertical direction to the controller through the remote control, and executes the control program periodically. In the control program, the movement speed of the end of the robot arm is converted into a target position, and the corresponding target joint angle is calculated based on the position. The error between the measured values ​​of the first inclination sensor and the second inclination sensor and the error conversion rate are used as the duty cycle of PWM through fuzzy control, and then the actuator is controlled to drive the joint movement so that the end of the robot arm reaches the target position. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present application and do not constitute an improper limitation of the present invention. In the drawings:

[0052] Figure 1 A structural diagram of the initial position of a shotcrete mechanical arm provided in an embodiment of the present invention;

[0053] Figure 2 A structural diagram of the working position of the shotcrete mechanical arm provided in an embodiment of the present invention;

[0054] Figure 3a A structural diagram of a first position of a boom provided by an embodiment of the present invention;

[0055] Figure 3b A structural diagram of a second position of a large arm provided in an embodiment of the present invention;

[0056] Figure 3c A structural diagram of a third position of a boom provided by an embodiment of the present invention;

[0057] Figure 3d A structural diagram of a fourth position of a large arm provided in an embodiment of the present invention;

[0058] Figure 4 A schematic flow chart of a method for controlling the posture of a shotcrete robot arm provided in an embodiment of the present invention.

[0059] in,

[0060] 1-mechanical arm; 11-telescopic arm; 12-big arm; 13-small arm; 14-spray gun;

[0061] 2-first inclination sensor; 3-second inclination sensor; 4-third inclination sensor;

[0062] 5-first rotary joint; 6-second rotary joint; 7-third rotary joint; 8-fourth rotary joint. DETAILED DESCRIPTION

[0063] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0064] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0065] In addition, in the description of the present invention, it should be understood that the orientations or positional relationships indicated by the terms "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0066] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0067] In the present invention, unless otherwise clearly specified and limited, the first feature "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0068] The present invention provides a spraying mechanical arm, which is used for a wet spraying engineering vehicle for concrete in a roadway. The end of the mechanical arm 1 is connected to a spray gun, and comprises a telescopic arm 11, a large arm 12, and a small arm 13 connected in sequence. One end of the telescopic arm 11 is installed on the body of the engineering vehicle. During use, the extension direction of the telescopic arm 11 is parallel to the roadway surface to be sprayed, and the telescopic arm 11 performs forward and backward telescopic movement. One end of the large arm 12 is connected to the other end of the telescopic arm 11 through a first rotary joint 5, and the other end of the large arm 12 is connected to one end of a small arm 13 through a second rotary joint 6. The spray gun 14 is connected to the small arm 13 through a third rotary joint 7.

[0069] In one embodiment, the rotation axes of the first swivel joint 5, the second swivel joint 6 and the third swivel joint 7 are parallel to the extension direction of the telescopic arm 11. Assume that the end is facing the surface to be sprayed and the front end is away from the surface to be sprayed. The upper arm 12 and the lower arm 13 generally move in a zigzag shape, and the end of the upper arm 12 can rotate around the direction of the telescopic arm 11, so that the end of the upper arm 12 can face the surface to be sprayed. The front end of the lower arm 13 is driven by the second swivel joint 6, so that the end of the lower arm 13 reaches the target spraying position, thereby controlling the vertical distance between the spray gun 14 and the surface to be sprayed and the vertical height between the spray gun 14 and the ground, and then adjusting the spray gun 14 to be perpendicular to the surface to be sprayed through the third swivel joint 7 to prevent the problem of high rebound rate of the spray slurry. That is, in the roadway coordinate system, the vertical distance between the spray gun 14 and the surface to be sprayed and the vertical height between the spray gun 14 and the ground are controlled by fine-tuning, and then a forward and backward movement is completed along the forward and backward movement to complete the spraying operation in a certain area, and the operation of the surface to be sprayed is completed in a repeated cycle.

[0070] The mechanical arm 1 further includes a first inclination sensor 2 provided at the upper arm 12 and a second inclination sensor 3 provided at the lower arm 13, wherein the measuring axis of the first inclination sensor 2 is parallel to and in the same direction as the rotation axis of the first rotary joint 5, and the measuring axis of the second inclination sensor 3 is parallel to and in the same direction as the rotation axis of the second rotary joint 6. The measurement values ​​of the first inclination sensor 2 and the second inclination sensor 3 are the rotation angles of the first rotary joint 5 and the second rotary joint 6, i.e., the angles between the upper arm 12 and the lower arm 13 and the initial positions.

[0071] In one embodiment, a swing link and a fourth swing joint 8 are further provided between the spray gun 14 and the third swing joint 7, one end of the swing link is connected to the third swing joint 7, and the other end is connected to the fourth swing joint 8, the spray gun 14 is connected to the swing link through the fourth swing joint 8, and the rotation axis of the fourth swing joint 8 is in the vertical direction. The fourth swing joint 8 can swing forward and backward relative to the roadway surface to be sprayed, and is used to adjust the spray gun 14 to be perpendicular to the surface to be sprayed, or spray forward along the direction of movement of the vehicle body.

[0072] In one embodiment, the spraying robot arm 1 further includes a third inclination sensor 4 installed on the connecting rod between the third swivel joint 7 and the spray gun 14, and the measuring axis of the third inclination sensor 4 is parallel to and in the same direction as the rotation axis of the third swivel joint 7. The third inclination sensor 4 is used to measure the angle between the spray gun 14 and the surface to be sprayed, so as to ensure that the spray gun 14 can be rotated to be perpendicular to the surface to be sprayed, so as to realize the automatic maintenance of the posture angle of the spray gun 14.

[0073] In one embodiment, a fifth swivel joint is provided between the telescopic arm 11 and the body of the engineering vehicle, and the rotation axis of the fifth swivel joint is in the vertical direction. The fifth swivel joint can drive the telescopic arm 11 to rotate parallel to the surface to be sprayed. Of course, it is understandable that, in the case of not providing the fifth swivel joint, the telescopic arm 11 can also be perpendicular to the surface to be sprayed by controlling the movement of the vehicle body.

[0074] In one embodiment, the present invention provides a method for controlling the posture of a shotcrete robot arm 1, using the aforementioned shotcrete robot arm control system, characterized in that it includes:

[0075] S1: Establishing a tunnel coordinate system OXYZ, adjusting the extension direction of the telescopic arm 11 to be along the OX direction, wherein the OX direction represents a direction parallel to the tunnel surface to be sprayed; the OY direction represents a direction perpendicular to the surface to be sprayed; and the OZ direction represents a direction perpendicular to the ground;

[0076] S2: Determine the period t of the controller executing the control program, and send the movement speed v of the end of the robot arm 1 in the OY direction to the controller through the remote controller. y and the velocity v in the OZ direction z ;

[0077] S3: The movement speed v of the end of the robot arm 1 is increased y 、v z Converted into the position of the end of the small arm 13 relative to the front end of the large arm 12 in the OY direction and the OZ direction at time t;

[0078] S4: Obtaining a target rotation angle α of the first rotary joint 5 and a target rotation angle β of the second rotary joint 6 according to the position of the end of the forearm 13 relative to the front end of the upper arm 12 in the OY direction and the OZ direction;

[0079] S5: The target rotation angles α and β of the first rotary joint 5 and the second rotary joint 6 are respectively compared with the measured values ​​jd of the first inclination sensor 2 and the second inclination sensor 3 1’ and jd 2’ Perform position closed-loop control to make the upper arm 12 and the lower arm 13 reach the target position;

[0080] S6: According to the measurement value jd of the third inclination sensor 4 3’ The angle between the spray gun 13 and the surface to be sprayed is determined, and the third swivel joint 7 is adjusted to make the spray gun 13 perpendicular to the surface to be sprayed.

[0081] As a preferred embodiment of the present invention, in step S3, the formula for calculating the target rotation angle α of the first rotary joint 5 and the target rotation angle β of the second rotary joint 6 is:

[0082] At time t, the position of the end of the small arm 13 relative to the front end of the large arm 12 in the OXYZ coordinate system is:

[0083] Z t =Z0+v z t;

[0084] Y t =Y0+v y t;

[0085] Where: Z t , Y t They respectively represent the distances of the end of the small arm 13 relative to the front end of the large arm 12 on the Y axis and the Z axis in the OXYZ coordinate system at time t, Z0 and Y0 are initial values, and t represents time;

[0086] By geometric method, we can get:

[0087] d1 sinα-d2 sinβ=Z t ;

[0088] d1 cosα+d2 cosβ=Y t ;

[0089] Wherein: d1 is the length of the upper arm 12, d2 is the length of the lower arm 13;

[0090] When it is necessary to change the distance between the spray gun 13 and the surface to be sprayed, z =0,v y ≠0; when it is necessary to change the height of the spray gun 13 relative to the ground, v z ≠0, v y =0;

[0091] Solving the above equations together, we get:

[0092] When Z t ≥0,

[0093] α=cos -1 (s-D1-D2) / (2*d1*d2)-cos -1 (s-D1+D2) / (2*d2*S)+cos -1 (Y t / S);

[0094] β=cos -1 (s-D1+D2) / (2*d2*S)-cos -1 (Y t / S);

[0095] When Z t <0,

[0096] α=cos -1 (s-D1-D2) / (2*d1*d2)-cos -1 (s-D1+D2) / (2*d2*S)-cos -1 (Y t / S);

[0097] β=cos -1 (s-D1+D2) / (2*d2*S)+cos -1 (Y t / S);

[0098] Where D1 = d1 2 ; D2 = d2 2 ; s = Z t 2 +Y t 2 ;

[0099] As a preferred embodiment of the present invention, in step S5, the target angles jd1 and jd2 of the first inclination sensor 2 and the second inclination sensor 3 are calculated according to the target rotation angle α of the first swivel joint 5 and the target rotation angle β of the second swivel joint 6, and the target angles jd1 and jd2 of the first inclination sensor 2 and the second inclination sensor 3 are compared with the current measurement value jd 1’ and jd 2’ The error between them is compensated for by an error angle to perform position closed-loop control; if the current measurement values ​​jd of the first inclination sensor 2 and the second inclination sensor 3 are 1’ and jd 2’ equal to the target angles jd1 and jd2, the upper arm 12 and the lower arm 13 reach the target position; if the current measurement values ​​jd of the first inclination sensor 2 and the second inclination sensor 3 are 1’ and jd 2’ If the target angles jd1 and jd2 are not equal, the error angle compensation will continue until the current measured value jd 1’ and jd 2′ Equal to the target angles jd1 and jd2.

[0100] The formula for converting the obtained target rotation angles α and β into the corresponding target angles jd1 and jd2 measured by the first inclination sensor 2 and the second inclination sensor 3 is:

[0101] When -90°≤α<270°, jd1=90°-α; when 270°≤α<360°, jd1=450°-α;

[0102] When -360°≤α<-270°, jd1=-270°-α;

[0103] When -90°≤β<270°, jd2=90°-β; when 270°≤β<360°, jd2=450°-β;

[0104] When -360°≤β<-270°, jd2=-270°-β.

[0105] Taking the upper arm 12 as an example, for α, when α>0, Figure 3a , 0°≤α<90°, jd1=90°-α, then 0° <jd1≤90°;

[0106] Figure 3b In the case of 90°≤α<180°, jd1=90°-α, at this time -90° <jd1≤0°;

[0107] Figure 3c In the case of 180°≤α<270°, jd1=90°-α, at this time -180° <jd1≤-90°;

[0108] Figure 3d In the case of 270°≤α<360°, jd1=450°-α, then 90° <jd1≤180°。

[0109] Anything not described in the present invention can be achieved by adopting or drawing on existing technologies.

[0110] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0111] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for controlling the posture of a shotcrete robot arm, characterized in that: Based on the shotcrete robot arm control system, the shotcrete robot arm control system is used to control the shotcrete robot arm; The spraying mechanical arm is used for wet spraying engineering vehicles for roadways. The end of the mechanical arm is connected to a spray gun, including a telescopic arm, a large arm, and a small arm connected in sequence; one end of the telescopic arm is installed on the body of the engineering vehicle; One end of the boom is connected to the other end of the telescopic arm through a first swivel joint; the other end of the boom is connected to one end of the forearm through a second swivel joint; the spray gun is connected to the forearm through a third swivel joint; the spraying mechanical arm also includes a first inclination sensor provided on the boom and a second inclination sensor provided on the forearm, respectively, a measuring axis of the first inclination sensor is parallel to and in the same direction as the rotation axis of the first swivel joint, and a measuring axis of the second inclination sensor is parallel to and in the same direction as the rotation axis of the second swivel joint; The control system of the shotcrete robot arm includes a remote controller, a controller and an actuator; the remote controller is used to send the movement speed of the end of the robot arm in the horizontal direction and the vertical direction to the controller; the controller is used to receive the movement speed data of the remote controller, and the measurement values ​​of the first inclination sensor, the second inclination sensor and the third inclination sensor, and can convert the movement speed data to obtain the corresponding target joint angle, and output the control signal according to the error between each target joint angle and the measurement value of the corresponding first inclination sensor, the second inclination sensor and the third inclination sensor and the error conversion rate; The actuator is used to drive the first rotary joint, the second rotary joint and the third rotary joint to move to a target joint angle according to a control signal output by the controller; The posture control method of the shotcrete mechanical arm comprises: S1: Establish the tunnel coordinate system OXYZ, and adjust the extension direction of the telescopic arm along the OX direction, where the OX direction represents the direction parallel to the tunnel surface to be sprayed; the OY direction represents the direction perpendicular to the surface to be sprayed; and the OZ direction represents the direction perpendicular to the ground; S2: Determine the cycle t of the controller executing the control program, and send the movement speed v of the end of the robot arm in the OY direction to the controller through the remote control y and the velocity v in the OZ direction z ; S3: Set the movement speed v of the end of the robot arm y 、v z Converted into the position of the end of the forearm relative to the front end of the upper arm in the OY direction and the OZ direction at time t; S4: Obtaining a target rotation angle α of the first rotary joint and a target rotation angle β of the second rotary joint according to the position of the end of the forearm relative to the front end of the upper arm in the OY direction and the OZ direction; S5: The target rotation angles α and β of the first rotary joint and the second rotary joint are respectively compared with the measured values ​​jd of the first inclination sensor and the second inclination sensor. 1’ and jd 2’ Perform position closed-loop control to make the boom and forearm reach the target position; S6: Based on the measured value jd of the third inclination sensor 3’ Determine the angle between the spray gun and the surface to be sprayed, and adjust the third swivel joint to make the spray gun perpendicular to the surface to be sprayed; In step S3, the formula for calculating the target rotation angle α of the first rotary joint and the target rotation angle β of the second rotary joint is: At time t, the position of the end of the forearm relative to the front end of the upper arm in the OXYZ coordinate system is: Z t =Z0+v z t; Y t =Y0+v y t; Where: Z t , Y t They respectively represent the distances of the end of the forearm relative to the front end of the large arm on the Y axis and the Z axis in the OXYZ coordinate system at time t, Z0 and Y0 are initial values, and t represents time; By geometric method we get: d1sinα-d2inβ=Z t ; d1cosα+d2cosβ=Y t ; Where: d1 is the length of the upper arm, d2 is the length of the lower arm; When you need to change the distance between the spray gun and the surface to be sprayed, use v z =0, v y ≠0; when the height of the spray gun relative to the ground needs to be changed, v z ≠0, v y =0; Solving the above equations together, we get: When Z t ≥0, α=cos -1 (s-D1-D2) / (2*d1*d2)-cos -1 (sD1+D2) / (2*d2*S)+cos -1 (Y t / S); β=cos -1 (s-D1+D2) / (2*d2*S)-cos -1 (Y t / S); When Z t <0, α=cos -1 (s-D1-D2) / (2*d1*d2)-cos -1 (s-D1+D2) / (2*d2*S)-cos -1 Y t / S); β=cos -1 (s-D1+D2) / (2*d2*S)+cos -1 (Y t / S); Where D1 = d1 2 ; D2 = d2 2 ; s = Z t 2 +Y t 2 ; .

2. The method for controlling the posture of a shotcrete robot arm according to claim 1, characterized in that: In step S5, the target angles jd1 and jd2 of the first inclination sensor and the second inclination sensor are calculated according to the target rotation angle α of the first swivel joint and the target rotation angle β of the second swivel joint, and the target angles jd1 and jd2 of the first inclination sensor and the second inclination sensor are compared with the current measurement value jd 1’ and jd 2’ The error between the first and second inclination sensors is compensated for by an error angle to perform position closed-loop control; if the current measured values ​​jd 1’ and jd 2’ equal to the target angles jd1 and jd2, the upper arm and the lower arm reach the target position; if the current measured values ​​jd of the first inclination sensor and the second inclination sensor are 1’ and jd 2’ If the target angles jd1 and jd2 are not equal, the error angle compensation will continue until the current measured value jd 1’ and jd 2’ Equal to the target angles jd1 and jd2.

3. A shotcrete robot arm, controlled based on the posture control method of a shotcrete robot arm according to any one of claims 1 to 2, characterized in that: The spraying mechanical arm is used for wet spraying engineering vehicles for roadways. The end of the mechanical arm is connected to a spray gun, including a telescopic arm, a large arm, and a small arm connected in sequence; one end of the telescopic arm is installed on the body of the engineering vehicle; One end of the boom is connected to the other end of the telescopic arm through a first swivel joint; the other end of the boom is connected to one end of the forearm through a second swivel joint; the spray gun is connected to the forearm through a third swivel joint; the spraying mechanical arm also includes a first inclination sensor provided on the boom and a second inclination sensor provided on the forearm, respectively, a measuring axis of the first inclination sensor is parallel to and in the same direction as the rotation axis of the first swivel joint, and a measuring axis of the second inclination sensor is parallel to and in the same direction as the rotation axis of the second swivel joint; The rotation axes of the first swivel joint, the second swivel joint and the third swivel joint are all parallel to the extension direction of the telescopic arm.

4. A shotcrete robot arm according to claim 3, characterized in that: A swing link and a fourth swing joint are also provided between the spray gun and the third swing joint. One end of the swing link is connected to the third swing joint, and the other end is connected to the fourth swing joint. The spray gun is connected to the swing link via the fourth swing joint, and the rotation axis of the fourth swing joint is in the vertical direction.

5. A shotcrete robot arm according to claim 3, characterized in that: It also includes a third inclination sensor installed on the connecting rod between the third swivel joint and the spray gun, and the measuring axis of the third inclination sensor is parallel to the rotation axis of the third swivel joint and is in the same direction.

6. A shotcrete robot arm according to claim 3, characterized in that: A fifth swivel joint is provided between the telescopic arm and the body of the engineering vehicle, and a rotation axis of the fifth swivel joint is along a vertical direction.

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