Fingertip-imitating parallel robot and control method thereof

Abstract

The fingertip-imitating parallel robot comprises a fingertip-imitating system, a transmission device, a power system, a frame and a control device, the fingertip-imitating system is installed at the tail end of the transmission device, the other end of the transmission device is connected with the power system, and the power system and the fingertip-imitating system are connected with the control device through wires. And the power system and the control device are fixed on the frame. The frame, the control device, the power system, the transmission device and the fingertip simulation system are distributed from top to bottom. The control device issues a command to the power system, the power system drives the transmission device, and the transmission device enables the fingertip simulation system to be kept in a required posture. According to the fingertip-imitating parallel robot, human fingers can be well imitated. According to the fingertip-imitating parallel robot, the universal ball joint is used as the connection between the driven arm and the movable platform, and the rolling action of human fingertips can be well simulated.

Description

Technical Field

[0001] The invention relates to the technical field of parallel robots and automatic control, and in particular to a fingertip-simulating parallel robot and a control method thereof. Background Art

[0002] In recent years, with the rapid development of robotics technology, a lot of energy and resources have been invested in the research of bionic robots at home and abroad. In these studies, the fingertips, which are mostly studied on dexterous hands, are a design that realizes bionic motion through a series mechanism, in which each motor independently controls one degree of freedom, thereby driving the fingertips to perform precise movements. This structure has become a more common solution in research due to its simplicity and easy control. Then, with different complex work scenarios and work requirements, when imitating special dexterous movements such as rolling, traditional robots cannot complete certain specific movements due to their complex structure and difficult control algorithms.

[0003] Compared with the series mechanism, the parallel fingertip motion mechanism is more precise, and the motor installed on the top simulates the stretching control of the human hand muscles. Due to the lack of imitation of fingertip rolling rotation, a ball joint is used for control. The new mechanical structure involves new mathematical solutions and models, and it is difficult to achieve bionic motion control. Summary of the invention

[0004] In view of the above problems, an object of the present invention is to provide a fingertip imitating parallel robot and a control method thereof.

[0005] The technical solution of the present invention is as follows:

[0006] A fingertip-simulating parallel robot includes a fingertip-simulating system, a transmission device, a power system, a frame, and a control device. The fingertip-simulating system is installed at the end of the transmission device, and the other end of the transmission device is connected to the power system. The power system and the fingertip-simulating system are connected to the control device through a wire, and the power system and the control device are fixed on the frame. From top to bottom, they are distributed as a frame, a control device, a power system, a transmission device, and a fingertip-simulating system. The control device issues a command to the power system, and the power system drives the transmission device, and the transmission device keeps the fingertip-simulating system in a required posture.

[0007] The fingertip-simulating system includes a silicone fingertip-simulating component, an attitude correction gyroscope, a moving platform, and a universal ball joint. The silicone fingertip-simulating component is fixed below the attitude correction gyroscope through a reliable connection. The attitude correction gyroscope is connected to the control device. The moving platform is connected to the top of the attitude correction gyroscope. A universal ball joint is fixed every 120° on the edge of the moving platform. The universal ball joint is connected to the transmission device. The transmission device drives the universal ball joint, and the universal ball joint drives the moving platform so that the silicone fingertip-simulating component reaches the expected attitude. The attitude correction gyroscope transmits signals to the control device through wires. The control device receives the signal and compares it with the required attitude and transmits the correction signal to the power system.

[0008] The transmission device includes a first connecting device, an active arm, a second connecting device, a driven arm, and a third connecting device. The upper end of the first connecting device is connected to the output shaft of the power system, the lower end of the first connecting device is connected to the active arm, the active arm is connected to the driven arm through the second connecting device, the second connecting device is composed of a T-shaped connecting piece, a fixing rod, a ball joint, a ball joint connecting rod, and a spring. The ball joints are fixed at both ends of the fixing rod and pass through the T-shaped connecting piece. The T-shaped connecting piece passes through the active arm, the ball joint is inserted into the joint cavity above the ball joint connecting rod, the ball joint connecting rod is inserted through the driven arm below, a spring connecting buckle is provided below the ball joint connecting rod, and the spring is connected. Both ends of the spring are connected to the ball joint connecting rod. The driven arm is composed of two aluminum hollow tubes. The driven arm and the second connecting device are left-right symmetrical structures. The driven arm is locked and connected to the third connecting device below without providing freedom. The third connecting device is fixed to the universal joint of the fingertip simulation system below.

[0009] The frame includes aluminum profiles, limit switches, 3D printed connectors, and limit switch fixings. A portion of the aluminum profiles constitutes an outer frame, and another portion of the aluminum profiles constitutes an equilateral triangle frame for fixing the power device. The equilateral triangle frame is fixed on the outer frame, and the limit switch is fixed on the equilateral triangle frame through the limit switch fixing. At the same time, the limit switch and the limit switch fixing are located at the highest point of the movable range of the active arm.

[0010] The power system includes a reduction gear cover, a reduction gear body, a stepper motor, an output shaft, a driving gear, a driven gear, and a belt. The stepper motor passes through the reduction gear body, the stepper motor is connected to the control device through a wire, the rotating shaft of the stepper motor is connected to the driving gear, the driving gear and the driven gear are driven by a belt, the driven gear is connected to the output shaft, the output shaft is connected to the first connecting device of the transmission device, the control device sends a command to the stepper motor through a wire, the stepper motor drives the driving gear, the driving gear drives the belt to drive the driven gear, and the driven gear drives the output shaft to rotate, thereby driving the transmission device.

[0011] The control device includes a host computer, a single-chip microcomputer, a driver, and a transformer power supply. The transformer power supply is connected to the driver through a wire, the driver is connected to the single-chip microcomputer, the single-chip microcomputer communicates with the host computer bidirectionally through a serial port, the single-chip microcomputer is connected to a posture correction gyroscope of a fingertip simulation system through a wire, and the driver is connected to a stepper motor of a power system through a wire.

[0012] A control method of a fingertip-simulating parallel robot includes the following steps:

[0013] 1) Start the host computer and the transformer power supply;

[0014] 2) The controller inputs the desired fingertip-simulating parallel robot posture through the host computer. After solving the problem, the host computer sends the required angle of the stepper motor to the single-chip microcomputer through the serial port. The single-chip microcomputer calculates the required number of pulses of the stepper motor and sends it to the driver. The driver drives the stepper motor 23 to operate. The output shaft of the power system rotates to drive the transmission device to drive the fingertip-simulating system to reach the desired posture.

[0015] 3) The posture correction gyroscope of the fingertip-simulating system transmits the actual posture of the fingertip-simulating system to the single-chip microcomputer through the wire. After comparison, the single-chip microcomputer sends the phase difference angle to the host computer, and repeats all steps except the first step in step 2) to correct the posture of the fingertip-simulating system 1;

[0016] Preferably, in the above steps, the parallel robot is provided with a response collision sensor to avoid responding beyond the motion range of the parallel robot, and returns the response to the host computer through the serial port for early warning.

[0017] Preferably, in the above steps, if the operator inputs the next posture without waiting for the parallel robot to complete the action, the host computer will automatically save the input action and feedback the current action. After the current action is completed, the unfinished command will be automatically executed.

[0018] Preferably, in the above steps, if the operator considers that the parallel robot is not operating properly, the operator can forcibly stop the robot through the host computer.

[0019] Preferably, in the above steps, the single chip microcomputer will further perform correction control on the posture of the parallel robot through a posture correction gyroscope to achieve a closed control loop.

[0020] The present invention is beneficial to:

[0021] 1) The fingertip-simulating parallel robot can well realize the bionics of human fingers. The fingertip-simulating parallel robot of the present invention uses a universal ball joint as the connection between the driven arm and the moving platform, and can well simulate the rolling action of human fingertips.

[0022] 2) The fingertip-simulating parallel robot adopts spring connection for a series of connections, which can effectively reduce the mechanical loss of the body and thus achieve long-term use.

[0023] 3) The fingertip-simulating parallel robot can achieve posture changes within a relatively small range. The fingertip-simulating parallel robot of the present invention drives the active arm to drive the passive arm through a stepper motor to achieve posture changes of the moving platform. After the upper computer solves the problem, the corresponding angle that the active arm needs to reach is sent to the single-chip microcomputer through the serial port. The single-chip microcomputer calculates the number of pulses required for the stepper motor to reach the angle and sends it to the driver. The driver drives the stepper motor to make the robot reach the corresponding posture. After testing, the error between the actual posture and the specified posture is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the three-dimensional structure of the fingertip imitating parallel robot of the present invention;

[0025] Figure 2 is a schematic diagram of the three-dimensional structure of the transmission device;

[0026] Figure 3 is a schematic diagram of the three-dimensional structure of the control device;

[0027] Figure 4 It is a control flow diagram of the parallel robot;

[0028] In the figure: 1. Fingertip-imitation system; 11. Fingertip-imitation component made of silicone material; 12. Gyroscope for posture correction; 13. Moving platform; 14. Universal ball joint; 2. Power system; 21. Gearbox cover; 22. Gearbox body; 23. Stepper motor; 24. Output shaft; 25. Driving gear; 26. Driven gear; 27. Belt; 3. Frame; 31. Aluminum profile; 32. 3D printed connector; 33. Limit switch; 34. Limit switch fixing; 4. Transmission device; 41. Active arm; 42. Driven arm; 43. Second connecting device; 44. Third connecting device; 45. First connecting device; 5. Control device; 51. Host computer; 52. Single chip microcomputer; 53. Driver; 54. Transformer power supply; 55. Transformer power supply. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and implementation methods, but the protection scope of the present invention is not limited thereto.

[0030] like Figures 1 to 3 As shown, a fingertip-simulating parallel robot should include a fingertip-simulating system 1, a transmission device 4, a power system 2, a frame 3, and a control device 5. The fingertip-simulating system is installed at the end of the transmission device 4, and the other end of the transmission device 4 is connected to the power system 2. The power system 2 and the fingertip-simulating system 1 are connected to the control device 5 through a wire, and the power system 2 and the control device 5 are fixed on the frame 3. From top to bottom, they are distributed as the frame 3, the control device 5, the power system 2, the transmission device 4, and the fingertip-simulating system 1.

[0031] The silicone fingertip imitation component 11 is reliably fixed below the posture correction gyroscope 12, the posture correction gyroscope 12 is connected to the control device 4, the posture correction gyroscope 12 is connected to the moving platform 13 above, a universal ball joint 14 is fixed every 120° on the edge of the moving platform 13, and the universal ball joint 14 is connected to the transmission device 4.

[0032] like Figure 2 As shown, the upper end of the first connecting device 45 is connected to the output shaft 24 of the power system 2, and the lower end of the first connecting device 45 is connected to the active arm 41. The active arm 41 is connected to the driven arm 42 through the second connecting device 43. The ball joints 432 are fixed at both ends of the fixing rod 434 and pass through the T-shaped connecting piece 435. The T-shaped connecting piece 435 passes through the active arm 41, and the ball joint is inserted into the joint cavity above the ball joint connecting rod 433. The ball joint connecting rod 433 is inserted through the driven arm 42 below. A spring connecting buckle is provided below the ball joint connecting rod 433 to connect the spring 431. Both ends of the spring are connected to the ball joint connecting rod 433. The driven arm 42 is composed of two aluminum hollow tubes. The driven arm 42 and the second connecting device 43 are of left-right symmetrical structure. The driven arm 42 is locked and connected to the third connecting device 44 below without providing freedom. The third connecting device 44 is fixed to the universal ball joint 14 of the fingertip simulation system 11 below.

[0033] like Figure 3 As shown, the power system 2 includes a reduction box cover 21, a reduction box body 22, a stepper motor 23, an output shaft 24, a driving gear 25, a driven gear 26, and a belt 27. The stepper motor 23 passes through the reduction box 22, and the stepper motor 23 is connected to the control device 5 through a wire. The rotating shaft of the stepper motor 23 is connected to the driving gear 25, and the driving gear 25 and the driven gear 26 are driven by the belt 27. The driven gear 26 is connected to the output shaft 24, and the output shaft 24 is connected to the first connecting member 45 of the transmission device 4.

[0034] The frame 3 includes an aluminum profile 31, a limit switch 33, a 3D printed connector 32, and a limit switch fixing part 34. A part of the aluminum profile 31 constitutes an outer frame of 80cm*80cm*50cm, and another part of the aluminum profile 31 constitutes an equilateral triangle frame for fixing the power device 2. The equilateral triangle frame is fixed on the outer frame of 80cm*80cm*50cm. The limit switch 33 is fixed on the equilateral triangle frame through the limit switch fixing part 34. At the same time, the limit switch 33 and the limit switch fixing part 34 are located at the highest point of the movable range of the active arm 41.

[0035] like Figure 4 A control method of a fingertip-simulating parallel robot is shown.

[0036] 1) Start the host computer 51 and start the transformer power supply 54.

[0037] 2) The controller inputs the desired fingertip-simulating parallel robot posture through the host computer 51. After solving the problem, the host computer 51 sends the required angle of the stepper motor 23 to the single-chip microcomputer 52 through the serial port. The single-chip microcomputer 52 calculates the required number of pulses of the stepper motor 23 and sends it to the driver 53. The driver 53 drives the stepper motor 23 to operate, and the output shaft 24 of the power system 2 rotates to drive the transmission device 4 to drive the fingertip-simulating system 1 to reach the desired posture.

[0038] 3) Posture correction of the fingertip-simulating system 1 The gyroscope 12 transmits the actual posture of the fingertip-simulating system 1 to the single-chip microcomputer 52 through a wire. After comparison, the single-chip microcomputer 52 sends the phase difference angle to the host computer 51, and repeats step 2) except the first step to correct the posture of the fingertip-simulating system 1.

[0039] It should be understood that the above embodiments are only used to illustrate the specific implementation of the technical solution of the present invention, and are not used to limit the scope of the present invention. After reading the present invention, the modifications and substitutions of various equivalent forms of the present invention by those skilled in the art all belong to the protection scope defined by the claims of this application.

Claims

1. A fingertip-simulating parallel robot, characterized in that: The invention comprises a frame (3), wherein a group of power systems (2) are arranged on the frame (3), and a group of the power systems (2) are respectively connected to transmission devices (4), wherein one end of the transmission device (4) is connected to the power system, and the other end is connected to the simulated fingertip system (1), and a group of the power systems (2) respectively drives the corresponding transmission devices, thereby driving the simulated fingertip system (1) to reach and maintain a set posture.

2. A fingertip-simulating parallel robot according to claim 1, characterized in that: It also comprises a control device (5), wherein the control device (5) is connected to the power system (2) and the fingertip-simulating system (1) via electrical signals and is used to control the fingertip-simulating system (1).

3. A fingertip-simulating parallel robot according to claim 2, characterized in that: The fingertip-simulating system (1) comprises a fingertip-simulating component (11), a posture correction gyroscope (12), a moving platform (13), and a universal ball joint (14); the fingertip-simulating component (11) is fixedly arranged below the posture correction gyroscope (12); the posture correction gyroscope (12) is connected to an electric signal of a control device (5); the moving platform (13) is connected above the posture correction gyroscope (12); a universal ball joint (14) is arranged on the edge of the moving platform (13); and the universal ball joint (14) corresponds to and is connected to a transmission device (4) in a one-to-one manner.

4. A fingertip-simulating parallel robot according to claim 1, characterized in that: The transmission device (4) comprises a first connecting device (45), an active arm (41), a second connecting device (43), a driven arm (42) and a third connecting device (44); one end of the first connecting device (45) is connected to an output shaft (24) of a power system (2), and the other end is connected to one end of the active arm (41); the other end of the active arm (41) is connected to one end of the driven arm (42) via the second connecting device (43); the other end of the driven arm (42) is locked and connected to one end of the third connecting device (44) without providing a degree of freedom; the other end of the third connecting device (44) is fixedly connected to a universal joint (14) of the fingertip simulation system (11).

5. A fingertip-simulating parallel robot according to claim 2, characterized in that: The power system (2) comprises a reduction box cover (21), a reduction box body (22), a stepper motor (23), an output shaft (24), a driving gear (25), a driven gear (26) and a belt (27); the stepper motor (23) is fixed on the reduction box body (22), the stepper motor (23) is connected to the control device (5) by electrical signals, the rotating shaft of the stepper motor (23) is connected to the driving gear (25), the driving gear (25) and the driven gear (26) of the reduction box body (22) are driven by the belt (27), the driven gear (26) is connected to the output shaft (24), and the output shaft (24) is connected to the first connecting device (45) of the transmission device (4).

6. A fingertip-simulating parallel robot according to claim 2, characterized in that: The control device (5) comprises a host computer (51), a single-chip microcomputer (52), a driver (53) and a transformer power supply (54); the transformer power supply (54) is connected to the driver (53), the driver (53) is connected to the single-chip microcomputer (52), the single-chip microcomputer (52) communicates bidirectionally with the host computer (51) via a serial port, the single-chip microcomputer (52) is connected to the fingertip simulation system (1) via electrical signals, and the driver (53) is connected to the power system (2) via electrical signals.

7. A fingertip-simulating parallel robot according to claim 4, characterized in that: The frame (3) comprises a frame body (31), a limit switch (33), a 3D printed connector (32) and a limit switch fixing member (34); the limit switch (33) is fixed to the frame body (31) via the limit switch fixing member (34), and the limit switch (33) and the limit switch fixing member (34) are located at the highest point of the movable range of the active arm (41).

8. A fingertip-simulating parallel robot according to claim 4, characterized in that: The second connecting device (43) comprises a T-shaped connecting piece (435), a fixing rod (434), a ball joint (432), a ball joint connecting rod (433) and a spring (431); both ends of the fixing rod (434) pass through the T-shaped connecting piece (435) and are symmetrically provided with ball joints (432) at both ends; the T-shaped connecting piece (435) is fixedly connected to the active arm (41); the ball joint (432) is inserted into the joint cavity above the ball joint connecting rod (433); the driven arm (42) is inserted below the ball joint connecting rod (433); a spring connecting buckle is provided on the side of the ball joint connecting rod (433); and both ends of the connecting spring (431) are respectively connected to the spring connecting buckle.

9. A fingertip-simulating parallel robot according to any one of claims 1 to 8, characterized in that: The steps include: 1) Start the host computer (51) and start the transformer power supply (54); 2) The control personnel input the desired fingertip-simulating parallel robot posture through the host computer (51), and the host computer (51) calculates and sends the required angle of the stepping motor (23) to the single-chip computer (52) through the serial port; 3) The single chip microcomputer (52) calculates the number of pulses required by the stepping motor (23) and sends it to the driver (53); the driver (53) drives the stepping motor (23) to operate; the output shaft (24) of the power system (2) rotates to drive the transmission device (4) to drive the universal joint (14); the universal joint (14) drives the moving platform (13) to make the fingertip simulation component (11) reach a desired posture. 4) The posture correction gyroscope (12) of the simulated fingertip system (1) transmits the actual posture of the simulated fingertip system (1) to the single-chip microcomputer (52) through a wire. The single-chip microcomputer (52) receives the signal and compares it with the required posture to transmit and correct it. After comparison, the phase difference angle is sent to the host computer (51), and step 3) is repeated to correct the posture of the simulated fingertip system (1).

10. A fingertip-simulating parallel robot according to any one of claims 1 to 8, characterized in that: In the step 2), if the next posture is input without waiting for the parallel robot to complete the action, the host computer will automatically save the input action and feedback the current action, and will automatically execute the unfinished command after the current action is completed.

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