High-power line-driven mechanical arm and control method thereof

Abstract

The invention provides a high-power line-driven mechanical arm and a control method thereof.Two driving motors are connected with two rope winding mechanisms correspondingly, rope tightness limiting switches are arranged at the front ends of the rope winding mechanisms, a driving motor control line and a tightness limiting switch signal line are connected to an embedded control system, and the two rope winding mechanisms pull the same load oppositely; the dual-drive motor drives the two winding drums to wind or unwind ropes so as to achieve load dragging. When the embedded control system detects that the limit switch is triggered, the rope releasing speed is automatically adjusted so as to tension the driving rope; the angle encoder measures the joint angle; according to the rope-driven mechanical arm, only the tightness limiting switch needs to be installed at the rope winding and unwinding end, the feedback requirement of the mechanism for the motor is reduced, and the problem that the driving rope is loosened in the rope-driven mechanical arm is effectively solved.

Description

Technical Field

[0001] The present application relates to the field of electrical equipment control technology, and in particular to a high-power line-driven robotic arm and a control method thereof. Background Art

[0002] In the design and manufacture of robotic arms, the tension of the drive rope (or drive cable) is an important issue. The drive rope is usually used to transmit power or control the movement of the robotic arm, ensuring that the robotic arm can accurately perform various actions during work. However, over time, the drive rope may lose proper tension due to wear, stretching or other reasons, which in turn affects the accuracy and reliability of the robotic arm.

[0003] Traditional tensioning uses a fixed tensioner and a single drive. The fixed tensioner often requires manual adjustment and cannot adapt to the dynamic changes of the drive rope during use, which can easily lead to insufficient or excessive tension, increased wear or cause the rope to rewind, affecting the poor performance of the robotic arm when performing complex tasks; the single-drive robotic arm has poor stability and is prone to vibration and swing during movement; the single-drive robotic arm has a short lifespan, and a single drive bears all the loads and stresses, which can easily lead to concentrated wear on components; the single-drive robotic arm has weak ability to perform complex tasks, and due to limitations in degrees of freedom and power output, it performs poorly when performing complex tasks.

[0004] Therefore, a new solution for high-power wire-driven robotic arms is needed. Summary of the invention

[0005] In view of this, the embodiments of this specification provide a high-power wire-driven robotic arm and a control method thereof.

[0006] The embodiments of this specification provide the following technical solutions:

[0007] The embodiment of the present specification provides a high-power wire drive robot arm, including: a first drive motor, a first drive motor reducer, a second drive motor, a second drive motor reducer, a first rope winding device, a second rope winding device, a first tightness detection device, a second tightness detection device, an angle encoder and an embedded control system;

[0008] The first drive motor reducer is connected to the first drive motor and the first rope winding device respectively; the second drive motor reducer is connected to the second drive motor and the second rope winding device respectively;

[0009] The first tightness detection device is installed at the front end of the first rope winding device; the second tightness detection device is installed at the front end of the second rope winding device;

[0010] The first drive motor is connected to the embedded control system; the second drive motor is connected to the embedded control system; the first drive motor and the second drive motor are respectively used to provide operating power for the robot arm, and cooperate with their respective corresponding drive motor reducers to adjust their respective corresponding rope winding devices to retract and release ropes;

[0011] The first tension detection device is connected to the embedded control system; the second tension detection device is connected to the embedded control system; the first tension detection device and the second tension detection device are respectively used to monitor the tension state of the corresponding driving rope in the wire-driven mechanical arm;

[0012] The angle encoder is connected to the embedded control system and is used to monitor and feedback the angle information of the robot arm joint;

[0013] The first drive motor is used to operate according to a set PWM duty cycle in the forward transport mode; the first drive motor is used to operate in the reverse direction with the second drive motor at the same PWM duty cycle; when the first tightness detection device or the second tightness detection device is triggered, the second drive motor adjusts the speed by adjusting the PWM duty cycle to automatically adjust the tightness of the rope;

[0014] The first drive motor is used to operate according to the set PWM duty cycle in the reverse transport mode; the second drive motor is used to operate in the opposite direction to the first drive motor with the same PWM duty cycle; when the second tightness detection device or the first tightness detection device is triggered, the first drive motor adjusts the speed by adjusting the PWM duty cycle to automatically adjust the tightness of the rope.

[0015] Furthermore, the first tightness detection device is provided with a first rope loose limit switch and a first rope tight limit switch;

[0016] The first rope loose limit switch is used to issue a rope loose alarm at the end of the first rope winding device; the first rope tight limit switch is used to issue a rope tight alarm at the end of the first rope winding device.

[0017] Furthermore, the second tightness detection device is provided with a second rope loose limit switch and a second rope tight limit switch;

[0018] The second rope loose limit switch is used to issue a rope loose alarm at the end of the second rope winding device; the second rope tight limit switch is used to issue a rope tight alarm at the end of the second rope winding device.

[0019] Furthermore, in the forward transport mode, if a first rope winding device end rope loose alarm or a second rope winding device end rope loose alarm is issued, the speed of the second drive motor decreases; if a first rope winding device end rope tight alarm or a second rope winding device end rope tight alarm is issued, the speed of the second drive motor increases.

[0020] Furthermore, in the reverse transport mode, if a first rope winding device end rope loose alarm or a second rope winding device end rope loose alarm is issued, the speed of the first drive motor decreases; if a first rope winding device end rope tight alarm or a second rope winding device end rope tight alarm is issued, the speed of the first drive motor increases.

[0021] Furthermore, the first drive motor is used to set the maximum PWM duty cycle to 60% in the forward transport mode, and the first rope winding device is in the rope collecting state; the first drive motor is used to set the maximum PWM duty cycle to 80% in the reverse transport mode, and the first rope winding device is in the rope releasing state.

[0022] Furthermore, the second drive motor is used to set the maximum PWM duty cycle to 60% in the reverse transport mode, and the second rope winding device is in the rope collecting state; the second drive motor is used to set the maximum PWM duty cycle to 80% in the forward transport mode, and the second rope winding device is in the rope releasing state.

[0023] Furthermore, it also includes: a human-machine interface module:

[0024] The human-machine interface module is connected to the embedded control system; the human-machine interface module is used to collect instructions issued by the user and visualize the parameters in the embedded control system.

[0025] The embodiments of this specification also provide a high-power wire-driven robotic arm control method, which uses the high-power wire-driven robotic arm described in any one of the above technical solutions to control the robotic arm to perform tasks by automatically adjusting the tightness of the rope.

[0026] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above technical solutions adopted in the embodiments of this specification include at least:

[0027] The embodiment of this specification has two independent drive devices, which control the two ends of the drive rope respectively to maintain appropriate tension during operation. In order to further improve the operating stability of the rope-driven robotic arm and the service life of the drive rope, automatic tensioning technology is introduced. This technology can monitor the tension of the drive rope in real time and automatically adjust it as needed to ensure that the drive rope is always in the best condition during the entire use process. The dual-drive robotic arm has good stability, and the dual drivers move in a balanced manner, reducing vibration and improving stability; the dual-drive robotic arm has a long life, and the load and stress are dispersed to the two drivers, reducing component wear and extending service life; the dual-drive robotic arm has strong ability to perform complex tasks, higher degrees of freedom and power output, and can complete complex and high-precision tasks, such as fine assembly, complex handling, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A framework diagram of an electric control system provided for a specific embodiment of the present invention;

[0030] Figure 2 A perspective view of a rope-driven mechanical arm structure provided by a specific embodiment of the present invention;

[0031] Figure 3 Another perspective view of the rope-driven manipulator structure provided by a specific embodiment of the present invention;

[0032] Figure 4 The overall flow chart of the program provided for the specific embodiment of the present invention;

[0033] Figure 5 A flow chart of a pre-tensioning rope program before starting a subroutine provided in a specific embodiment of the present invention;

[0034] Figure 6 A flowchart of maintaining tension when starting a subroutine provided for a specific embodiment of the present invention;

[0035] Figure 7 A flow chart of adjusting the motor speed when starting a subroutine provided in a specific embodiment of the present invention;

[0036] Figure 8 A schematic diagram of the structure of a first tightness detection device provided in a specific embodiment of the present invention;

[0037] Fig. 9 This is a schematic structural diagram of a second tightness detection device provided in a specific embodiment of the present invention.

[0038] Among them, 1. the first driving motor; 2. the first driving motor reducer; 3. the first rope winding device; 4. the first tightness detection device; 5. the second driving motor; 6. the second driving motor reducer; 7. the second rope winding device; 8. the second tightness detection device; 9. the angle encoder. DETAILED DESCRIPTION

[0039] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0040] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0041] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0042] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0043] The terms "first", "second", etc. in the specification and claims of this application and the drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a series of steps, processes, methods, etc. are not limited to the listed steps, but may optionally include steps that are not listed, or may optionally include other step elements inherent to these processes, methods, products or devices.

[0044] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the examples can be practiced without these specific details.

[0045] Traditional tensioning uses a fixed tensioner and a single drive. The fixed tensioner often requires manual adjustment and cannot adapt to the dynamic changes of the drive rope during use, which can easily lead to insufficient or excessive tension, increased wear or cause the rope to rewind; the single-drive robotic arm has poor stability and is prone to vibration and swing during movement; the single-drive robotic arm has a short lifespan, and a single drive bears all the loads and stresses, which can easily lead to concentrated wear on components; the single-drive robotic arm has weak ability to execute complex tasks, and due to limitations in degrees of freedom and power output, it performs poorly when performing complex tasks.

[0046] In order to solve the problems existing in the prior art, the inventors found that it is necessary to solve them by means of electronic control.

[0047] Based on this, the embodiment of this specification proposes a new solution for a high-power wire-driven robotic arm. According to the forward transport and reverse transport modes, one of the drive motors is set to the rope collecting drive, and the other drive motor is set to the rope releasing drive. The alarm status of the tensioning detection device is detected at regular intervals, the current rope tensioning status is judged according to the alarm status, and the rope releasing drive speed is adjusted according to the tensioning status. When the rope loose alarm at the first rope winding device end or the rope loose alarm at the second rope winding device end is detected, the rope releasing speed of the rope releasing drive decreases to prevent the rope from being too loose; when the rope tight alarm at the first rope winding device end and the rope tight alarm at the second rope winding device end are detected, the rope releasing drive speed increases to prevent the rope from being too tight.

[0048] The technical solutions provided by various embodiments of the present application are described below in conjunction with the accompanying drawings.

[0049] Figure 1 , Figure 2 and Figure 3 The electrical control system architecture diagram and the rope-driven manipulator structure perspective diagram provided by the embodiments of the present invention are shown in FIG. Figure 1 , Figure 2 and Figure 3 As shown, the present invention provides a high-power wire drive robot arm and a control method thereof, including: a first drive motor, a first drive motor reducer, a second drive motor, a second drive motor reducer, a first rope winding device, a second rope winding device, a second rope winding device, a first tightness detection device, a second tightness detection device, an angle encoder, an embedded control system, and a human-machine interface.

[0050] The first drive motor reducer is connected to the first drive motor and the first rope winding device respectively; the second drive motor reducer is connected to the second drive motor and the second rope winding device respectively; the first tightness detection device is installed at the front end of the first rope winding device; the second tightness detection device is installed at the front end of the second rope winding device; the first drive motor is connected to the embedded control system; the second drive motor is connected to the embedded control system; the first tightness detection device is connected to the embedded control system; the second tightness detection device is connected to the embedded control system; the human-machine interface is connected to the embedded control system; the angle encoder is connected to the embedded control system.

[0051] Figure 4 , Figure 5 , Figure 6 and Figure 7 They are respectively the overall program flow chart provided in the embodiment of the present invention, the rope pre-tensioning program flow chart before the subroutine starts, the flow chart for maintaining tension when the subroutine starts, and the flow chart for adjusting the motor speed when the subroutine starts. After the equipment is started, the program runs in a 10HZ frequency cycle, and in each cycle, the rope pre-tensioning program before the subroutine starts, the rope pre-tensioning program when the subroutine starts, the tensioning program when the subroutine starts, and the motor speed adjustment program when the subroutine starts are executed in sequence.

[0052] Furthermore, the tensioning ready state is: before starting, the first rope winding device end rope loose alarm does not sound, the first rope winding device end rope tight alarm does not sound, the second rope winding device end rope loose alarm does not sound, the second rope winding device end rope tight alarm does not sound, and the PWM duty cycle of the first drive motor and the second drive motor is 0%.

[0053] Furthermore, in the pre-tensioning rope program stage before the subroutine is started: if tensioning is not ready, the first drive motor drives the rope to be collected to eliminate the loose rope alarm at the end of the first rope winding device, the first drive motor drives the rope to be released to eliminate the tight rope alarm at the end of the first rope winding device, the second drive motor drives the rope to be collected to eliminate the loose rope alarm at the end of the second rope winding device, and the second drive motor drives the rope to be released to eliminate the tight rope alarm at the end of the second rope winding device.

[0054] Further, when the subroutine is started, the tensioning stage is maintained: if the tensioning is ready and in the forward transport mode, the first rope winding device has an end rope tension alarm and the second rope winding device has an end rope tension alarm, the current second drive motor PWM value is recorded as PWM1_1 and the second drive motor target speed is increased until the first rope winding device end rope tension alarm is cancelled or the second rope winding device end rope tension alarm is cancelled, the second drive motor PWM value is recorded as PWM1_2 when the first rope winding device end rope tension alarm is cancelled or the second rope winding device end rope tension alarm is cancelled, and the second drive motor is set The target duty cycle is a1*PWM1_1+(1-a1)*PWM1_2; if tensioning is ready and in forward transport mode, the second rope winding device will trigger a loose rope alarm, record the current PWM value of the second drive motor as PWM1_1 and decrease the target speed of the second drive motor until the loose rope alarm at the second rope winding device is cancelled, record the PWM value of the second drive motor as PWM1_2 when the loose rope alarm at the second rope winding device is cancelled, and set the target duty cycle of the second drive motor to a1*PWM1_1+(1-a1)*PWM1_2.

[0055] Furthermore, the tensioning stage is maintained when the subroutine is started: if the tensioning is ready and in the reverse transport mode, the first rope winding device has a rope tight alarm and the second rope winding device has a rope tight alarm, the current PWM value of the first drive motor is recorded as PWM2_1 and the target speed of the second drive motor is increased until the rope tight alarm at the first rope winding device end or the rope tight alarm at the second rope winding device end is cancelled, the PWM value of the first drive motor is recorded as PWM2_2 when the rope tight alarm at the first rope winding device end or the rope tight alarm at the second rope winding device end is cancelled, and the target duty cycle of the first drive motor is set to a1*PWM2_1+(1-a1)*PWM2_2; if the tensioning is ready and in the reverse transport mode, the first rope winding device has a rope loose alarm, the current PWM value of the first drive motor is recorded as PWM2_1 and the target speed of the first drive motor is decreased until the rope loose alarm at the first rope winding device end is cancelled, the PWM value of the first drive motor is recorded as PWM2_2 when the rope loose alarm at the first rope winding device end is cancelled, and the target duty cycle of the first drive motor is set to a1*PWM2_1+(1-a1)*PWM2_2.

[0056] Preferably, a1 is set to 0.6.

[0057] Furthermore, the motor speed adjustment stage is performed when the subroutine is started: if the tension is ready and in the forward transport mode, the target PWM value of the first drive motor is set to 50% after receiving the start command, and the first rope winding device driven by the first drive motor is in the rope collecting state, and the target PWM value of the second drive motor is set to 50%, and the second rope winding device driven by the second drive motor is in the rope releasing state; if the tension is ready and in the reverse transport mode, the target PWM value of the first drive motor is set to 50% after receiving the start command, and the first rope winding device driven by the first drive motor is in the rope releasing state, and the target PWM value of the second drive motor is set to 50%, and the second rope winding device driven by the second drive motor is in the rope collecting state; if the tension is ready and in the forward transport mode, the target PWM value of the first drive motor is set to 0% and the target PWM value of the second drive motor is set to 0% after receiving the stop command; if the tension is ready and in the reverse transport mode, the target PWM value of the first drive motor is set to 0% and the target PWM value of the second drive motor is set to 0% after receiving the stop command.

[0058] Furthermore, in the motor speed adjustment stage when the subroutine is started: the first drive motor is used to set the maximum PWM duty cycle to 60% in the forward transport mode; the first drive motor is used to set the maximum PWM duty cycle to 80% in the reverse transport mode; the second drive motor is used to set the maximum PWM duty cycle to 60% in the reverse transport mode; the second drive motor is used to set the maximum PWM duty cycle to 80% in the forward transport mode; the target duty cycle will be set in an incremental manner on the first drive motor and the second drive motor to avoid motor damage caused by sudden changes in the duty cycle.

[0059] Furthermore, the angle encoder is used to obtain current joint angle data.

[0060] The same or similar parts between the various embodiments in this specification can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the product embodiment described later, since it corresponds to the method, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

[0061] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A high-power line-driven robotic arm, characterized in that: include: A first drive motor, a first drive motor reducer, a second drive motor, a second drive motor reducer, a first rope winding device, a second rope winding device, a first tightness detection device, a second tightness detection device, an angle encoder and an embedded control system; The first drive motor reducer is connected to the first drive motor and the first rope winding device respectively; the second drive motor reducer is connected to the second drive motor and the second rope winding device respectively; The first tightness detection device is installed at the front end of the first rope winding device; The second tightness detection device is installed at the front end of the second rope winding device; The first drive motor is connected to the embedded control system; the second drive motor is connected to the embedded control system; the first drive motor and the second drive motor are respectively used to provide operating power for the robot arm, and cooperate with their respective corresponding drive motor reducers to adjust their respective corresponding rope winding devices to retract and release ropes; The first tension detection device is connected to the embedded control system; the second tension detection device is connected to the embedded control system; the first tension detection device and the second tension detection device are respectively used to monitor the tension state of the corresponding driving rope in the wire-driven mechanical arm; The angle encoder is connected to the embedded control system and is used to monitor and feedback the angle information of the robot arm joint; The first drive motor is used to operate according to a set PWM duty cycle in the forward transport mode; The first drive motor is used to run in the opposite direction to the second drive motor with the same PWM duty cycle; When the first tightness detection device or the second tightness detection device is triggered, the second drive motor adjusts the speed by adjusting the PWM duty cycle to automatically adjust the tightness of the rope; The first drive motor is used to operate according to a set PWM duty cycle in the reverse transport mode; The second drive motor is used to run in the opposite direction to the first drive motor with the same PWM duty cycle; When the second tightness detection device or the first tightness detection device is triggered, the first drive motor adjusts the speed by adjusting the PWM duty cycle to automatically adjust the tightness of the rope.

2. The high-power line-driven mechanical arm according to claim 1, characterized in that: The first tightness detection device is provided with a first rope loose limit switch and a first rope tight limit switch; The first rope loose limit switch is used to issue a rope loose alarm at the end of the first rope winding device; the first rope tight limit switch is used to issue a rope tight alarm at the end of the first rope winding device.

3. The high-power wire-driven mechanical arm according to claim 1, characterized in that: The second tightness detection device is provided with a second rope loose limit switch and a second rope tight limit switch; The second rope loose limit switch is used to issue a rope loose alarm at the end of the second rope winding device; the second rope tight limit switch is used to issue a rope tight alarm at the end of the second rope winding device.

4. The high-power wire-driven mechanical arm according to claim 1, 2 or 3, characterized in that: In the forward transport mode, if the first rope winding device end rope loose alarm or the second rope winding device end rope loose alarm is issued, the speed of the second drive motor decreases; if the first rope winding device end rope tight alarm or the second rope winding device end rope tight alarm is issued, the speed of the second drive motor increases.

5. The high-power wire-driven mechanical arm according to claim 1, 2 or 3, characterized in that: In the reverse transport mode, if the first rope winding device end rope loose alarm or the second rope winding device end rope loose alarm is issued, the speed of the first drive motor decreases; if the first rope winding device end rope tight alarm or the second rope winding device end rope tight alarm is issued, the speed of the first drive motor increases.

6. The high-power wire-driven mechanical arm according to claim 1, characterized in that: The first drive motor is used to set the maximum PWM duty cycle to 60% in the forward transport mode, and the first rope winding device is in the rope collecting state; the first drive motor is used to set the maximum PWM duty cycle to 80% in the reverse transport mode, and the first rope winding device is in the rope releasing state.

7. The high-power wire-driven mechanical arm according to claim 1, characterized in that: The second drive motor is used to set the maximum PWM duty cycle to 60% in the reverse transport mode, and the second rope winding device is in the rope collecting state; the second drive motor is used to set the maximum PWM duty cycle to 80% in the forward transport mode, and the second rope winding device is in the rope releasing state.

8. The high-power wire-driven mechanical arm according to claim 1, characterized in that: Also includes: Human Machine Interface Module: The human-machine interface module is connected to the embedded control system; the human-machine interface module is used to collect instructions issued by the user and visualize the parameters in the embedded control system.

9. A high-power line-driven robot arm control method, characterized in that: The high-power wire-driven robotic arm as described in any one of claims 1 to 8 is used to control the robotic arm to perform tasks by automatically adjusting the tension of the rope.

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