Flywheel-driven mechanical arm device, control system and control method

Abstract

The invention relates to the technical field of mechanical arm design and control, in particular to a flywheel-driven mechanical arm device, a control system and a control method. A main body structure of the mechanical arm device comprises a base, an arm rod, a joint and a flywheel driving device. The control system comprises a rotating speed reference regulator and a motor rotating speed controller. The motor rotating speed controller drives the flywheel driving device to track the target rotating speed according to the error between the target rotating speed and the actual rotating speed of the flywheel, the inner frame and the outer frame, and the actual pose of the mechanical arm tracks the target pose. A reaction flywheel is adopted as a power source of the mechanical arm, torque of the same size is output through high-speed rotation of the flywheel and change of the rotating speed of a deflection frame, the weight of the mechanical arm and the complexity of joints are remarkably reduced, a complex and heavy transmission structure is omitted, and motion control over the mechanical arm is achieved. The control precision and the response speed are improved, and the advantages of being simple in structure, small in rotational inertia, high in reliability, high in control precision, high in response speed and the like are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical arm design and control, and in particular to a flywheel-driven mechanical arm device, a control system and a control method. Background Art

[0002] Existing robotic arms have different driving modes such as motor module drive, rope (wire) drive, and fluid drive. The motor module drive has the advantages of high control accuracy and mature control technology, but the cost is large and bulky motors and reducer components, which cause the robot arm to have a large moment of inertia, which is not conducive to high-speed and long-distance motion occasions; fluid drive mainly includes two methods: pneumatic and hydraulic drive. Since it relies on a large and complex energy preparation and distribution system, such as oil tanks, solenoid valves, valve blocks, pumps, etc., it not only causes severe heating and low transmission efficiency during frequent switching work, but also has the risk of leakage, and the nonlinear mechanical properties of the fluid make the position control stability poor; rope (wire) drive places the drive motor at the back of the base, thereby reducing the moment of inertia of the robot arm, but the resulting structures such as vias, pulleys, and winding drums serving the rope (wire) transmission are very complex. In the case of long-distance transmission, the hysteresis deformation effect of the rope (wire) is also very obvious, resulting in poor terminal positioning accuracy and load capacity. At the same time, there are different defects such as fatigue fracture and friction loss, which is not conducive to achieving long-distance, high-precision, and high-reliability motion control tasks. Therefore, there is an urgent need for a robotic arm with a new drive mode that has a simple transmission structure, small rotational inertia, high reliability, fast response speed, and high control accuracy. Summary of the invention

[0003] The purpose of the present invention is to avoid the shortcomings of the prior art and provide a flywheel-driven robotic arm device and control system, which omits the complex and bulky transmission structure, uses a reaction flywheel as the power source of the robotic arm, and realizes the motion control of the robotic arm.

[0004] To achieve the above object, the technical solution adopted by the present invention is: the flywheel-driven mechanical arm device is characterized by comprising a base, a first arm is provided on the base through a first joint, a first flywheel driving device is provided at the upper end of the first arm, the first arm is connected to the second arm through a second joint, and a second flywheel driving device is provided at the upper end of the second arm; The first flywheel drive device and the second flywheel drive device have the same structure. The first flywheel drive device includes a flywheel, which is installed on the flywheel motor rotor shaft of the flywheel drive motor. A motor end cover is arranged on the upper part of the flywheel drive motor, and a flywheel speed measurement and control module is also arranged on the flywheel drive motor.

[0005] The first arm and the second arm adopt a rigid structure, the first flywheel drive device on the first arm is set to be a single first right flywheel drive device and a first left flywheel drive device or two, and the second flywheel drive device on the second arm is set to be a second right flywheel drive device and a second left flywheel drive device.

[0006] The first flywheel drive device also includes an inner frame installed on the flywheel motor rotor shaft, the inner frame is connected to the inner frame motor rotor shaft of the inner frame drive motor, and the inner frame drive motor is also provided with an inner frame speed measurement and control module.

[0007] An outer frame is also installed on the inner frame motor rotor shaft, and the outer frame is connected to the outer frame motor rotor shaft of the outer frame drive motor. An outer frame speed measurement and control module is also arranged on the outer frame drive motor.

[0008] The first arm and the second arm are replaced by a first flexible arm and a second flexible arm with a flexible structure, a third joint is arranged between the first flexible arm and the second flexible arm, a fourth joint is arranged at the front end of the second flexible arm, the third joint and the fourth joint have the same structure, the third joint includes a joint shell, and a joint left end cover and a joint right end cover respectively connected to the first flexible arm and the second flexible arm are arranged at both ends of the joint shell.

[0009] A first flywheel driving device is also arranged in the joint housings of the third joint and the fourth joint.

[0010] The flywheel speed measurement and control module, the inner frame speed measurement and control module and the outer frame speed measurement and control module realize the measurement and control of the flywheel, the inner frame and the outer frame through an angle sensor, an angular velocity sensor, a motor drive unit or a motor control unit.

[0011] The flywheel is made of steel, brass, bronze or cast iron.

[0012] A control system for a flywheel-driven mechanical arm device is characterized in that it includes a speed reference regulator and a motor speed controller. The speed reference regulator calculates the target speed of the flywheel and the inner frame and the outer frame according to the error between the target posture and the actual posture of the mechanical arm; the motor speed controller drives the flywheel drive device to track the target speed according to the error between the target speed and the actual speed of the flywheel and the inner frame and the outer frame, so as to realize that the actual posture of the mechanical arm tracks the target posture.

[0013] A control method for a flywheel-driven mechanical arm device is characterized by adopting closed-loop feedback control, comprising the following steps: (1) The speed reference regulator obtains the target posture signal of the manipulator and the real-time posture signal of the manipulator, compares the two signals and obtains the difference as the posture error. The speed reference regulator uses the posture error signal as the input signal for calculation and conversion to obtain the target speed of the flywheel, inner frame and outer frame; (2) The motor speed controller obtains the target speed signal and the real-time speed signal of the flywheel of the flywheel drive device, and then compares the two signals to obtain the difference as a speed error signal. The motor speed controller uses the speed error signal as an input signal to drive the flywheel device to track the target speed. (3) According to the principle of action and reaction, the reaction inertia force caused by the rotation of the flywheel and its posture change will act on the robot arm through the left and right end covers of each joint, ultimately causing the movement posture of the robot arm to change; Furthermore, the real-time position and posture of the robot arm during operation will be taken as an input signal by the speed reference regulator, thereby forming a closed-loop feedback control to achieve precise control of the flywheel-driven robot arm device system.

[0014] The beneficial effects of the present invention are as follows: the flywheel-driven robotic arm device, control system and control method adopt a reaction flywheel as the power source of the robotic arm, and output a torque of the same magnitude through the high-speed rotation of the flywheel and the change in the rotation speed of the deflection frame, which significantly reduces the weight of the robotic arm and the complexity of the joints, eliminates the complex and bulky transmission structure, and realizes the motion control of the robotic arm; it is beneficial to improve the control accuracy and response speed, and has the advantages of simple structure, small moment of inertia, high reliability, high control accuracy, fast response speed, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the principle of the flywheel-driven mechanical arm device of the present invention; Figure 2 It is a structural schematic diagram of a first flywheel driving device of a flywheel-driven mechanical arm device of the present invention; Figure 3 is a schematic diagram of a rigid mechanical arm driven by a flywheel of the present invention; Figure 4 It is a schematic diagram of a control system of a flywheel-driven rigid mechanical arm device of the present invention; Figure 5 A schematic diagram of a flexible mechanical arm driven by a control moment gyro of the present invention; Figure 6 It is a schematic diagram of the appearance structure of the joints of the flexible mechanical arm driven by the control torque gyro of the present invention; Figure 7A schematic structural diagram of a preferred flywheel driving device for the joints of a flexible mechanical arm driven by a control torque gyro of the present invention; Figure 8 This is a schematic structural diagram of another preferred flywheel drive device for controlling the joints of a flexible robotic arm driven by a torque gyro according to the present invention.

[0016] In the figure, 1, base; 2, first joint; 3, first arm; 4, first flywheel drive device; 4-1, first left flywheel drive device; 4-2, first right flywheel drive device; 4-3, flywheel; 4-4, flywheel drive motor; 4-5, flywheel motor rotor shaft; 4-6, motor end cover; 4-7, flywheel speed measurement and control module; 4-8, outer frame; 4-9, outer frame motor rotor shaft; 4-10, outer frame drive motor; 4-11, outer frame speed measurement and control module ; 4-12, inner frame; 4-13, inner frame motor rotor shaft; 4-14, inner frame drive motor; 4-15, inner frame speed measurement and control module; 5, second joint; 6, second arm; 7, second flywheel drive device; 7-1, second left flywheel drive device; 7-2, second right flywheel drive device; 8, first flexible arm; 9, second flexible arm; 10, third joint; 11, fourth joint; 12, joint left end cover; 13, joint housing; 14, joint right end cover. DETAILED DESCRIPTION

[0017] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0018] In order to achieve the above object, the present invention provides the following specific implementation methods: Figure 1 and 2 As shown, the flywheel-driven mechanical arm device is characterized in that it includes a base 1, a first arm 3 is provided on the base 1 through a first joint 2, a first flywheel driving device 4 is provided on the upper end of the first arm 3, the first arm 3 is connected to the second arm 6 through a second joint 5, and a second flywheel driving device 7 is provided on the upper end of the second arm 6; The first flywheel drive device 4 and the second flywheel drive device 7 have the same structure. The first flywheel drive device 4 includes a flywheel 4-3, which is mounted on a flywheel motor rotor shaft 4-5 of a flywheel drive motor 4-4. A motor end cover 4-6 is provided on the upper part of the flywheel drive motor 4-4. A flywheel speed measurement and control module 4-7 is also provided on the flywheel drive motor 4-4. The flywheel speed measurement and control module 4-7 adjusts the output torque size and direction of the flywheel drive device by controlling the rotation of the flywheel 4-3 and (or) the deflection of the flywheel motor rotor shaft 4-5.

[0019] like Figure 3As shown, the first arm 3 and the second arm 6 adopt a rigid structure, the first flywheel drive device 4 on the first arm 3 is set as a first right flywheel drive device 4-2 and a first left flywheel drive device 4-1, and the second flywheel drive device 7 on the second arm 6 is set as a second right flywheel drive device 7-2 and a second left flywheel drive device 7-1.

[0020] like Figure 7 As shown, the first flywheel drive device 4 also includes an inner frame 4-12 installed on the flywheel motor rotor shaft 4-5, and the inner frame 4-12 is connected to the inner frame motor rotor shaft 4-13 of the inner frame drive motor 4-14. The inner frame drive motor 4-14 is also provided with an inner frame speed measurement and control module 4-15.

[0021] like Figure 8 As shown, an outer frame 4-8 is also installed on the inner frame motor rotor shaft 4-13, and the outer frame 4-8 is connected to the outer frame motor rotor shaft 4-9 of the outer frame drive motor 4-10. The outer frame drive motor 4-10 is also provided with an outer frame speed measurement and control module 4-11.

[0022] like Figure 5 and 6 As shown, the first arm 3 and the second arm 6 are replaced by the first flexible arm 8 and the second flexible arm 9 with a flexible structure, a third joint 10 is arranged between the first flexible arm 8 and the second flexible arm 9, a fourth joint 11 is arranged at the front end of the second flexible arm 9, the third joint 10 and the fourth joint 11 have the same structure, the third joint 10 includes a joint housing 13, and the joint housing 13 has a joint left end cover 12 and a joint right end cover 14 respectively connected to the first flexible arm 8 and the second flexible arm 9. The joint housing 13 of the third joint 10 and the fourth joint 11 is also provided with a first flywheel drive device 4.

[0023] The flywheel speed measurement and control module 4-7, the inner frame speed measurement and control module 4-15 and the outer frame speed measurement and control module 4-11 realize the measurement and control of the flywheel 4-3, the inner frame 4-12 and the outer frame 4-8 through an angle sensor or an angular velocity sensor, a motor drive unit or a motor control unit.

[0024] The flywheel 4-3 is made of steel, brass, bronze or cast iron.

[0025] like Figure 4As shown, a control system of a flywheel-driven robotic arm device is characterized in that it includes a speed reference regulator and a motor speed controller. The speed reference regulator calculates the target speed of the inner frame 4-12 and the outer frame 4-8 of the flywheel 4-3 according to the error between the target posture and the actual posture of the robotic arm; the motor speed controller drives the flywheel drive device to track the target speed according to the error between the target speed and the actual speed of the flywheel 4-3 and the inner and outer frames, so as to realize that the actual posture of the robotic arm tracks the target posture.

[0026] A control method for a flywheel-driven mechanical arm device control system, characterized in that closed-loop feedback control is adopted, comprising the following steps: (1) The speed reference regulator obtains the target posture signal of the manipulator and the real-time posture signal of the manipulator, compares the two signals and obtains the difference as the posture error. The speed reference regulator uses the posture error signal as the input signal to calculate and convert it to obtain the target speed of the flywheel 4-3, the inner frame 4-12 and the outer frame 4-8; (2) The motor speed controller obtains the target speed signal and the real-time speed signal of the flywheel 4-3 of the flywheel drive device, and then compares the two signals to obtain the difference as a speed error signal. The motor speed controller uses the speed error signal as an input signal to drive the flywheel device to track the target speed. (3) According to the principle of action and reaction, the reaction inertia force caused by the rotation of flywheel 4-3 and its posture change will act on the robot arm through the left end cover and the right end cover of each joint, eventually causing the movement posture of the robot arm to change; Furthermore, the real-time position and posture of the robot arm during operation will be taken as an input signal by the speed reference regulator, thereby forming a closed-loop feedback control to achieve precise control of the flywheel-driven robot arm device system.

[0027] The flywheel-driven mechanical arm device described above, when working, the rotation direction of the flywheel 4-3 is parallel to a certain rotation direction of the first arm 3 relative to the base 1. The first right flywheel drive device 4-2 and the first left flywheel drive device 4-1 are vertically staggered and installed on the first arm 3, and the rotation direction of the flywheel 4-3 is parallel to another rotation direction of the first arm 3 relative to the base 1. According to the principle of action and reaction, the reaction inertia force caused by the rotation of the flywheel 4-3 will act on the first arm 3 through the motor end cover 4-6, and finally cause the movement posture of the mechanical arm to change.

[0028] When the robotic arm is working, the control system measures or calculates the actual joint angle value of the robotic arm in real time, calculates the error of the joint angle value, and based on the dynamics of the robotic arm, calculates the target amount of the flywheel speed that can generate the corresponding control torque in real time. The flywheel speed measurement and control module 4-7 measures the actual speed of the flywheel 4-3 and drives the flywheel drive motor to track the target amount. The flywheel 4-3 generates a corresponding reaction torque acting on the robotic arm, thereby changing the joint angle to track the target joint angle, and the cycle continues.

[0029] The flywheel-driven mechanical arm device, such as Figure 5-Figure 7 As shown, the flywheel drive device is installed inside the joint housing 13 of the third joint 10, the joint right end cover 14 is connected to the stator of the inner frame drive motor 4-14, the inner frame 4-12 is connected to the inner frame motor rotor shaft 4-13, the inner frame motor rotor shaft 4-13 is installed in the joint housing 13 through a bearing, and is driven by the inner frame drive motor 4-14. The stator of the flywheel drive motor 4-4 is connected to the inner frame 4-12, the flywheel 4-3 is connected to the flywheel motor rotor shaft 4-5, the flywheel motor rotor shaft 4-5 is installed on the inner frame 4-12 through a bearing, and is driven by the flywheel drive motor 4-4, and the flywheel motor rotor shaft 4-5 is perpendicularly crossed with the inner frame motor rotor shaft 4-13.

[0030] According to the principle of action and reaction, the reaction inertia force caused by the rotation of the flywheel 4-3 and its posture change will act on the robot through the left end cover and the right end cover of the third joint 10, and finally cause the movement posture of the robot to change. When the robot is working, the control system measures or calculates the actual posture of the robot in real time, calculates the posture error, and calculates the target amount of the flywheel speed and the inner frame speed that can generate the corresponding control torque in real time based on the dynamics of the flexible robot.

[0031] The flywheel speed measurement and control module 4-7 measures the actual speed of the flywheel 4-3 and drives the flywheel drive motor 4-4 to track the flywheel speed target, and the inner frame speed measurement and control module 4-15 measures the actual speed of the inner frame 4-12 and drives the inner frame drive motor 4-14 to track the inner frame speed target. This preferred single-frame flywheel drive device solution is suitable for occasions with smaller loads.

[0032] Another preferred flywheel drive device scheme is as follows Figure 8As shown, it is installed in the joint housing 13. Specifically, the joint right end cover 14 is connected to the stator of the outer frame drive motor 4-10, and the outer frame motor rotor shaft 4-9 is installed in the joint housing 13 through a bearing. The stator of the inner frame drive motor 4-14 is connected to the outer frame 4-8, and the inner frame 4-12 is connected to the inner frame motor rotor shaft 4-13. The inner frame motor rotor shaft 4-13 is installed on the outer frame 4-8 through a bearing, driven by the inner frame drive motor 4-14, and perpendicularly crosses the outer frame motor rotor shaft 4-9. The stator of the flywheel drive motor 4-4 is connected to the inner frame 4-12, and the flywheel 4-3 is connected to the flywheel motor rotor shaft 4-5. The flywheel motor rotor shaft 4-5 is installed on the inner frame 4-12 through a bearing, driven by the flywheel drive motor 4-4, and the flywheel motor rotor shaft 4-5 is perpendicularly crossed with the inner frame motor rotor shaft 4-13.

[0033] According to the principle of action and reaction, the reaction inertia force caused by the rotation of the flywheel 4-3 and its posture change will act on the robot through the left end cover and the right end cover of the third joint 10, and finally cause the motion posture of the robot to change. When the robot is working, the control system measures or calculates the actual posture of the robot in real time, calculates the posture error, and calculates the flywheel speed and the target amount of the inner and outer frame speeds that can generate the corresponding control torque based on the dynamics of the flexible robot in real time. The flywheel speed measurement and control module 4-7 measures the actual speed of the flywheel and drives the flywheel drive motor 4-4 to track the flywheel speed target, the inner frame speed measurement and control module 4-15 measures the actual speed of the inner frame 4-12 and drives the inner frame drive motor 4-14 to track the inner frame 4-12 speed target, and the outer frame speed measurement and control module 4-11 measures the actual speed of the outer frame 4-8 and drives the outer frame drive motor 4-10 to track the outer frame 4-8 speed target.

[0034] The flywheel-driven mechanical arm device is suitable for occasions with larger loads, and is also suitable for different occasions such as on-orbit operation, aerial refueling, medical surgery, etc.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A flywheel-driven mechanical arm device, characterized in that The invention comprises a base (1), wherein a first arm (3) is arranged on the base (1) via a first joint (2), a first flywheel driving device (4) is arranged at the upper end of the first arm (3), the first arm (3) is connected to a second arm (6) via a second joint (5), and a second flywheel driving device (7) is arranged at the upper end of the second arm (6); The first flywheel drive device (4) and the second flywheel drive device (7) have the same structure. The first flywheel drive device (4) comprises a flywheel (4-3). The flywheel (4-3) is mounted on a flywheel motor rotor shaft (4-5) of a flywheel drive motor (4-4). A motor end cover (4-6) is disposed on the upper part of the flywheel drive motor (4-4). A flywheel speed measurement and control module (4-7) is also disposed on the flywheel drive motor (4-4).

2. A flywheel driven mechanical arm device as claimed in claim 1, characterized in that: The first arm (3) and the second arm (6) are rigid structures. The first flywheel drive device (4) on the first arm (3) is configured as a first right flywheel drive device (4-2) and a first left flywheel drive device (4-1) or two, and the second flywheel drive device (7) on the second arm (6) is configured as a second right flywheel drive device (7-2) and a second left flywheel drive device (7-1) in pairs.

3. A flywheel driven mechanical arm device as claimed in claim 1 or 2, characterized in that: The first flywheel drive device (4) further comprises an inner frame (4-12) mounted on the flywheel motor rotor shaft (4-5), the inner frame (4-12) being connected to the inner frame motor rotor shaft (4-13) of the inner frame drive motor (4-14), and the inner frame drive motor (4-14) is also provided with an inner frame speed measurement and control module (4-15).

4. A flywheel driven mechanical arm device as claimed in claim 3, characterized in that: An outer frame (4-8) is also mounted on the inner frame motor rotor shaft (4-13); the outer frame (4-8) is connected to an outer frame motor rotor shaft (4-9) of an outer frame drive motor (4-10); and an outer frame speed measurement and control module (4-11) is also provided on the outer frame drive motor (4-10).

5. A flywheel driven mechanical arm device as claimed in claim 1, characterized in that: The first arm (3) and the second arm (6) are replaced by a first flexible arm (8) and a second flexible arm (9) with a flexible structure. A third joint (10) is arranged between the first flexible arm (8) and the second flexible arm (9). A fourth joint (11) is arranged at the front end of the second flexible arm (9). The third joint (10) and the fourth joint (11) have the same structure. The third joint (10) comprises a joint housing (13). A joint left end cover (12) and a joint right end cover (14) connected to the first flexible arm (8) and the second flexible arm (9) are arranged at both ends of the joint housing (13). A first flywheel driving device (4) is also arranged in the joint housing (13) of the third joint (10) and the fourth joint (11).

6. A flywheel driven mechanical arm device as claimed in claim 1, 2, 4 or 5, characterized in that: The flywheel speed measurement and control module (4-7), the inner frame speed measurement and control module (4-15) and the outer frame speed measurement and control module (4-11) realize the measurement and control of the flywheel (4-3), the inner frame (4-12) and the outer frame (4-8) through an angle sensor, an angular velocity sensor, a motor drive unit or a motor control unit.

7. A flywheel driven mechanical arm device as claimed in claim 6, characterized in that: The flywheel (4-3) is made of steel, brass, bronze or cast iron.

8. The control system of a flywheel-driven mechanical arm device according to claim 1, characterized in that: It comprises a speed reference regulator and a motor speed controller. The speed reference regulator calculates the target speed of the flywheel (4-3) and the inner frame (4-12) and the outer frame (4-8) according to the error between the target posture and the actual posture of the robot arm. The motor speed controller drives the flywheel drive device to track the target speed according to the error between the target speed and the actual speed of the flywheel (4-3) and the inner and outer frames, so as to achieve the tracking of the target posture by the actual posture of the robot arm.

9. The control method of a flywheel driven mechanical arm device according to claim 1, characterized in that: Adopt closed-loop feedback control, including the following steps: (1) The speed reference regulator obtains the target posture signal of the robot arm and the real-time posture signal of the robot arm, compares the two signals and obtains the difference as the posture error. The speed reference regulator uses the posture error signal as an input signal to calculate and convert it to obtain the target speed of the flywheel (4-3), the inner frame (4-12) and the outer frame (4-8); (2) The motor speed controller obtains the target speed signal and the real-time speed signal of the flywheel (4-3) of the flywheel drive device, and then compares the two signals to obtain the difference as a speed error signal. The motor speed controller uses the speed error signal as an input signal to drive the flywheel device to track the target speed. (3) According to the principle of action and reaction, the reaction inertia force caused by the rotation of the flywheel (4-3) and its posture change will act on the robot arm through the left and right end covers of each joint, ultimately causing the movement posture of the robot arm to change.

10. A control method for a flywheel-driven mechanical arm device as claimed in claim 9, characterized in that: The real-time position and posture of the robot arm during operation will be taken as an input signal by the speed reference regulator, thereby forming a closed-loop feedback control to achieve precise control of the flywheel-driven robot arm device system.

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