A heterogeneous dual-bus cooperative control method and system for a dual-arm robot

Abstract

The application discloses a heterogeneous double-bus cooperative control method and system of a dual-arm robot, and relates to the technical field of robot control.The method comprises the following steps: S1, acquiring an arm vector segment and a terminal vector segment; S2, acquiring an arm communication bus protocol message; S3, acquiring a terminal communication bus protocol message; S4, heterogeneous double-bus cooperative control.The application can realize seamless access of a heterogeneous terminal: the arm communication bus and the terminal communication bus are completely independent in the physical layer, the electrical layer and the address space, and the two do not share transceivers, cables or address spaces, fundamentally eliminating bandwidth contention, protocol conflicts and address conflicts when the heterogeneous terminal is accessed, ensuring stable control cycles and no data frame loss.Through the heterogeneous double-bus parallel topology, physical isolation and independent control of the arm and the terminal are realized, and protocol conflicts and bandwidth contention are eliminated.

Description

Technical Field

[0001] This invention relates to the field of robot control technology, specifically to a heterogeneous dual-bus cooperative control method and system for a dual-arm robot. Background Technology

[0002] The demand for dual-arm robot upper body systems is rapidly growing in scenarios such as scientific research experiments, flexible production lines, and service operations. Such systems need to drive a large number of joints under a unified time reference and simultaneously collect the status and visual information of all joints to support the generation of data-driven operation strategies.

[0003] In the process of realizing this invention, the inventors discovered that existing multi-degree-of-freedom dual-arm robot systems have at least the following problems: 1. Heterogeneous end units are difficult to connect to end effector units with their own drive systems. The communication protocols, message formats and baud rates used by their drivers are often inconsistent with those of the arm joint motors. If the two are connected in parallel to the same communication bus, bandwidth contention, protocol conflicts and address conflicts will occur, resulting in control cycle jitter, data frame loss or even bus interruption.

[0004] 2. Multi-source observation data are difficult to align in time. The sampling frequencies of observations from different sources are different. If they are simply spliced ​​together in the manner of "taking the latest value from each", it will introduce uncertain time misalignment and cause deviation between the recorded data and the actual physical process.

[0005] 3. Lack of overload protection mechanism for long-term operation. When the joint motor maintains its position for a long time or gets stuck, it is easy to enter a continuous high current state. If there is no monitoring and unloading mechanism independent of the main control circuit, it will cause the motor to overheat and be damaged. Summary of the Invention

[0006] This invention provides a heterogeneous dual-bus cooperative control method and system for a dual-arm robot to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A heterogeneous dual-bus cooperative control method for a dual-arm robot includes the following steps: S1. Obtain arm vector segment and end effector vector segment: The host controller generates a unified motion vector and divides the unified motion vector into several continuous segments according to a predetermined prefix order. The continuous segments include at least the arm vector segment corresponding to the arm mechanism and the end effector vector segment corresponding to the end effector unit. S2. Obtain arm communication bus protocol message: The host controller converts the arm vector segment into an arm communication bus protocol message through the first communication converter; S3. Obtain the terminal communication bus protocol message: The host controller converts the terminal vector segment into a terminal communication bus protocol message through the second communication converter; S4. Heterogeneous Dual-Bus Cooperative Control: The host controller sends out the arm communication bus protocol message and the end-effector communication bus protocol message in parallel to synchronously drive the arm mechanism and the end-effector execution unit within the same control cycle.

[0008] As a preferred embodiment of the present invention, the method further includes a time alignment and fusion step of multi-source observation data: The observation fusion module acquires the arm joint angle of the joint module, the state variables of the end effector, and the visual information of the binocular vision module in each acquisition cycle, including: The observation fusion module uses a time window mean alignment method for high-frequency observations: taking the timestamp of the current acquisition frame as the center, a time window with the same width as the acquisition period is selected, and the arithmetic mean of all high-frequency frames falling within the time window is calculated according to the dimension as the observation corresponding to the acquisition frame. Then, the observations are spliced ​​into a unified observation vector in a fixed order, and finally, together with the visual information, they are sent to the strategy model.

[0009] As a preferred embodiment of the present invention, the method further includes a graded overload protection step: The overload protection unit acquires the current parameters, temperature parameters, load rate parameters, and status flag parameters of all joint motors in batches through a single group read command at fixed intervals. When the overload protection unit detects that any of the following unloading conditions are met, it performs an unloading operation on the joint motor: a. Set the driver status flags; b. The temperature of the joint motor exceeds the first temperature threshold. c. The joint motor current exceeds the current threshold and the duration exceeds the first time threshold; d. The load rate of the joint motor exceeds the load threshold and the duration exceeds the second time threshold; e. The sum of the currents of all the joint motors on the same bus exceeds the bus current budget and the duration exceeds the third time threshold.

[0010] As a preferred embodiment of the present invention, the graded overload protection step further includes a recovery strategy: a. After the unloading operation is performed, continue to monitor the temperature of the joint motor. When the temperature of the joint motor drops below the recovery threshold and the status flag is cleared, the joint motor is re-enabled with the reduced torque upper limit. b. If the same joint motor repeatedly triggers unloading within a limited number of times, then automatic recovery will stop and a report will be sent to the host controller.

[0011] A heterogeneous dual-bus cooperative control system for a dual-arm robot includes: Frame; The arm mechanism is provided in two sets, symmetrically arranged on the frame. Each set of the arm mechanism consists of seven joint modules connected in series, and each joint module is equipped with a joint motor. The end effector unit is detachably mounted to the end output port of the joint module via an end interface flange; A binocular vision module is mounted on the frame and points to the common working area in front of the two sets of arm mechanisms; The control and wiring harness system adopts a heterogeneous dual-bus parallel topology, comprising a host controller, a first communication converter, an arm communication bus, a distribution board, a second communication converter, and an end communication bus, wherein: The host controller is connected to the arm communication bus via the first communication converter, and the power distribution board is electrically connected to the joint module. The host controller is connected to the end communication bus via the second communication converter, and the driver of the end execution unit is connected in series to the end communication bus.

[0012] As a preferred embodiment of the present invention, the control and harness system further includes a power supply unit, which includes an arm power supply unit and an end power supply unit. The arm power supply unit is used to supply power to the joint module, and the end power supply unit is used to supply power to the end effector unit.

[0013] As a preferred embodiment of the present invention, the power supply unit further includes an emergency stop switch for cutting off all drive power. One end of the emergency stop switch is connected in series with the output end of the arm power supply unit and the end power supply unit, and the other end of the emergency stop switch is connected to the power distribution board and the end execution unit respectively.

[0014] As a preferred embodiment of the present invention, the seven joint modules are connected in a daisy-chain manner on the arm communication bus.

[0015] As a preferred embodiment of the present invention, the control and harness system further includes an observation fusion module, which acquires the arm joint angle of the joint module, the state quantity of the end effector unit, and the visual information of the binocular vision module in each acquisition cycle.

[0016] As a preferred embodiment of the present invention, the arbitration segment rate of the arm communication bus is 1 Mbps and the data segment rate is 5 Mbps; the end communication bus is a serial bus with a rate of 1 Mbps.

[0017] This invention provides a heterogeneous dual-bus cooperative control method and system for a dual-arm robot. It has the following beneficial effects: 1. This invention enables seamless access to heterogeneous terminals: The arm communication bus and the terminal communication bus are completely independent in terms of physical layer, electrical layer and address space. They do not share transceivers, cables and address spaces, which fundamentally eliminates bandwidth contention, protocol conflicts and address conflicts when accessing heterogeneous terminals, ensuring stable control cycle and no data frame loss. Through the heterogeneous dual-bus parallel topology, physical isolation and independent control of the arm and terminal are achieved, eliminating protocol conflicts and bandwidth contention.

[0018] 2. This invention can achieve precise time alignment of multi-source observation data: It adopts the time window mean alignment method, takes the timestamp of the acquisition frame as the center, takes the window with equal width according to the acquisition period, and calculates the mean of all high-frequency frames in the window according to the dimension as the observation of that frame. This eliminates the time misalignment between observation sources with different sampling frequencies, minimizes the deviation between the recorded data and the real physical process, and solves the time misalignment problem of multi-source heterogeneous observation data.

[0019] 3. This invention intelligently ensures safe operation during long-term operation through graded overload protection: The overload protection unit operates independently of the main control circuit, and obtains the status of all joint motors in batches by reading them in a single group. It triggers unloading in a graded manner according to five conditions: status flag bit, temperature, continuous current, continuous load rate, and bus current budget. It also has a strategy of self-recovery of torque reduction after cooling and self-recovery after multiple triggers, which effectively prevents joint motors from overheating and being damaged. Attached Figure Description

[0020] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a functional module block diagram of the system of the present invention; Figure 3 This is a perspective view of the complete double-arm machine of the present invention; Figure 4 This is a perspective view of the arm mechanism in this invention; In the picture: 1. Frame; 2. Arm mechanism; 200. Joint module; 201. First joint module; 202. Second joint module; 203. Third joint module; 204. Fourth joint module; 205. Fifth joint module; 206. Sixth joint module; 207. Seventh joint module; 3. Binocular vision module. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Please see Figures 1-4 This invention provides a heterogeneous dual-bus cooperative control system for a dual-arm robot. The system consists of a frame 1, an arm mechanism 2, an end effector unit, a binocular vision module 3, and a control and wiring harness system, as described in detail below: Please see Figure 3 and Figure 4 The arm mechanism 2 has two sets, such as Figure 3 In the state shown, the two sets of arm mechanisms 2 are symmetrically arranged on the frame 1, forming a symmetrical layout. Each set of arm mechanisms 2 consists of seven joint modules 200 connected in series. Each joint module 200 is equipped with a joint motor (not shown in the figure). Figure 4 As shown, the seven joint modules 200 are the first joint module 201, the second joint module 202, the third joint module 203, the fourth joint module 204, the fifth joint module 205, the sixth joint module 206, and the seventh joint module 207. The first joint module 201, the second joint module 202, the third joint module 203, the fourth joint module 204, the fifth joint module 205, the sixth joint module 206, and the seventh joint module 207 are connected in a daisy chain. Each of the first joint module 201 to the seventh joint module 207 has an integrated joint motor, that is, each arm mechanism 2 is equipped with seven joint motors, and the two arm mechanisms are equipped with a total of fourteen joint motors. The number of joint motors in the arm mechanism 2 is strictly consistent with the number of its degrees of freedom (7 joint motors correspond to 7 degrees of freedom). No additional motors are set on the arm body specifically for driving the end effector unit. Please see Figure 4 The end effector (not shown in the figure) is detachably mounted to the end output port of the joint module 200 via the end interface flange. Since our company has applied for relevant patents and it is not a technical problem that needs to be solved in this invention, it will not be described further. The binocular vision module 3 is mounted on the frame 1 and points to the common working area in front of the two sets of arm mechanisms 2. Its two imaging units are arranged at intervals in the horizontal direction, with parallel optical axes pointing to the common working area in front of the two sets of arm mechanisms. Since the binocular vision module 3 is mounted on the support 1 between the two arms rather than on the arms, its pose relative to the base coordinate system remains constant during operation. It does not need to be recalibrated with external parameters as the arms move. The output depth information can be directly fused with the arm joint angle in the same base coordinate system. Please see Figure 2 The control and harness system adopts a heterogeneous dual-bus parallel topology, which includes a host controller, a first communication converter, an arm communication bus, a power distribution board, a second communication converter, an end communication bus, a power supply unit, and an observation fusion module, wherein: The host controller is connected to the arm communication bus via the first communication converter, and the power distribution board is electrically connected to the joint module 200. The arbitration segment rate of the arm communication bus is 1 Mbps and the data segment rate is 5 Mbps. The seven joint motors of the same arm mechanism 2 are connected in series on the bus in a daisy chain manner, and each joint motor has a unique bus address. The host controller is connected to the end communication bus via the second communication converter. The driver of the end execution unit is connected in series to the end communication bus. The end communication bus is a serial bus with a speed of 1Mbps. The power supply unit includes an arm power supply unit and an end power supply unit. The arm power supply unit supplies power to the joint module 200, and the end power supply unit supplies power to the end effector. The arm communication bus and the end communication bus are completely independent at the physical and electrical levels. They do not share transceivers, cables, or address spaces, so they do not compete for bandwidth or conflict with each other. They are also powered by independent power supply units. The arm power supply is distributed to each joint motor via a power communication composite interface (not shown in the figure, but located on the power distribution board) through a distribution board. In order to cut off all drive power in case of an abnormality, the power supply unit also includes an emergency stop switch. Specifically, one end of the emergency stop switch is connected in series with the output of the arm power supply unit and the end power supply unit, and the other end of the emergency stop switch is connected to the distribution board and the end execution unit respectively. In each acquisition cycle, the observation fusion module acquires the arm joint angles of the joint module 200, the state variables of the end effector, and the visual information of the binocular vision module 3. Specifically, in each acquisition cycle, the observation fusion module reads the arm joint angles (seven dimensions per arm, fourteen dimensions in total for both arms), the state variables of the end effector transmitted back through independent channels, and the visual information (i.e., image and depth information) output by the binocular vision module 3. To address the issue of inconsistent sampling frequencies among different observation sources, the observation fusion module employs a time window mean alignment method for high-frequency observations: a time window of equal width to the acquisition period is selected, centered on the timestamp of the current acquisition frame. The arithmetic mean of all high-frequency frames falling within this window is calculated along its dimensions and used as the observation for that acquisition frame, instead of directly taking the latest frame within the window. This ensures that each observation component has a consistent representative interval on the time axis, eliminating time misalignment caused by frequency differences. The aligned components are then concatenated in a fixed order to form a unified observation vector, which is fed into the strategy model along with the visual information. It should be noted that: Figure 2 The image shows the arm communication bus (right), the power distribution board (right), the arm communication bus (left), and the power distribution board (left). Since the present invention has two sets of arm mechanisms 2, which are symmetrical, the arm communication bus (left) and the arm communication bus (right) are exactly the same, and the power distribution board (left) and the power distribution board (right) are exactly the same. Therefore, in the above description, the left and right are not distinguished.

[0023] Please see Figure 1 A heterogeneous dual-bus cooperative control method for a dual-arm robot includes the following steps: S1. Obtain the arm vector segment and the end effector vector segment: The upper controller generates a unified motion vector and divides the unified motion vector into several continuous segments according to a predetermined prefix order. The continuous segments include at least the arm vector segment corresponding to the arm mechanism 2 and the end effector vector segment corresponding to the end effector unit. S2. Obtain arm communication bus protocol message: The host controller converts the arm vector segment into an arm communication bus protocol message through the first communication converter; S3. Obtain the terminal communication bus protocol message: The upper controller converts the terminal vector segment into a terminal communication bus protocol message through the second communication converter; S4. Heterogeneous dual-bus collaborative control: The upper controller sends arm communication bus protocol messages and end communication bus protocol messages in parallel to synchronously drive the arm mechanism 2 and the end execution unit within the same control cycle; The above method also includes time alignment and fusion steps for multi-source observation data: The observation fusion module acquires the arm joint angle of the joint module 200, the state variables of the end effector unit, and the visual information of the binocular vision module 3 in each acquisition cycle, including: The observation fusion module uses a time window mean alignment method for high-frequency observations: taking the timestamp of the current acquisition frame as the center, a time window with the same width as the acquisition period is taken, and the arithmetic mean of all high-frequency frames falling within the time window is calculated according to the dimension as the observation corresponding to the acquisition frame. Then, the observations are spliced ​​into a unified observation vector in a fixed order, and finally, along with the visual information, they are sent to the strategy model. The strategy model is an algorithm model in the upper controller, which can be obtained by conventional means of those skilled in the art. The above method also includes a graded overload protection step: The overload protection unit acquires the current, temperature, load rate, and status flag parameters of all joint motors in batches using a single group read command at fixed intervals. When the overload protection unit detects that any of the following unloading conditions are met, it performs an unloading operation on the joint motors: a. Set the driver status flags; b. The joint motor temperature exceeds the first temperature threshold; c. The joint motor current exceeds the current threshold and the duration exceeds the first time threshold; d. The joint motor load rate exceeds the load threshold and the duration exceeds the second time threshold; e. The sum of the currents of all joint motors on the same bus exceeds the bus current budget and the duration exceeds the third time threshold.

[0024] The graded overload protection process also includes a recovery strategy: a. After the unloading operation is performed, continue to monitor the joint motor temperature. When the joint motor temperature drops below the recovery threshold and the status flag is cleared, re-enable the joint motor with the reduced torque upper limit. b. If the same joint motor is repeatedly triggered to unload within a limited number of times, the automatic recovery will stop and a report will be sent to the upper controller. In summary, the operating logic of this invention is as follows: When the whole machine is working, the binocular vision module 3 collects images and depth information of the working area and uploads them to the observation fusion module 3. The observation fusion module sends the visual information and the unified observation vector into the strategy model. The strategy model (i.e., the upper controller) outputs a unified action vector, which is split by the distribution module and sent out in parallel by the heterogeneous dual bus. The two sets of arm mechanisms 2 complete a large range of pose adjustment. The end effector completes the end action through its own bus. The overload protection unit runs in parallel throughout the process to ensure the safety of the drive system.

[0025] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A heterogeneous dual-bus cooperative control method for a dual-arm robot, characterized in that, Includes the following steps: S1. Obtain arm vector segment and end effector vector segment: The host controller generates a unified motion vector and divides the unified motion vector into several continuous segments according to a predetermined prefix order. The continuous segments include at least the arm vector segment corresponding to the arm mechanism and the end effector vector segment corresponding to the end effector unit. S2. Obtain arm communication bus protocol message: The host controller converts the arm vector segment into an arm communication bus protocol message through the first communication converter; S3. Obtain the terminal communication bus protocol message: The host controller converts the terminal vector segment into a terminal communication bus protocol message through the second communication converter; S4. Heterogeneous Dual-Bus Cooperative Control: The host controller sends out the arm communication bus protocol message and the end-effector communication bus protocol message in parallel to synchronously drive the arm mechanism and the end-effector execution unit within the same control cycle.

2. The heterogeneous dual-bus cooperative control method for a dual-arm robot according to claim 1, characterized in that, The method also includes a time alignment and fusion step for multi-source observation data: The observation fusion module acquires the arm joint angle of the joint module, the state variables of the end effector, and the visual information of the binocular vision module in each acquisition cycle, including: The observation fusion module uses a time window mean alignment method for high-frequency observations: taking the timestamp of the current acquisition frame as the center, a time window with the same width as the acquisition period is selected, and the arithmetic mean of all high-frequency frames falling within the time window is calculated according to the dimension as the observation corresponding to the acquisition frame. Then, the observations are spliced ​​into a unified observation vector in a fixed order, and finally, together with the visual information, they are sent to the strategy model.

3. The heterogeneous dual-bus cooperative control method for a dual-arm robot according to claim 1, characterized in that, The method also includes a graded overload protection step: The overload protection unit acquires the current parameters, temperature parameters, load rate parameters, and status flag parameters of all joint motors in batches through a single group read command at fixed intervals. When the overload protection unit detects that any of the following unloading conditions are met, it performs an unloading operation on the joint motor: a. Set the driver status flags; b. The temperature of the joint motor exceeds the first temperature threshold. c. The joint motor current exceeds the current threshold and the duration exceeds the first time threshold; d. The load rate of the joint motor exceeds the load threshold and the duration exceeds the second time threshold; e. The sum of the currents of all the joint motors on the same bus exceeds the bus current budget and the duration exceeds the third time threshold.

4. The heterogeneous dual-bus cooperative control method for a dual-arm robot according to claim 3, characterized in that, The graded overload protection steps also include a recovery strategy: a. After the unloading operation is performed, continue to monitor the temperature of the joint motor. When the temperature of the joint motor drops below the recovery threshold and the status flag is cleared, the joint motor is re-enabled with the reduced torque upper limit. b. If the same joint motor repeatedly triggers unloading within a limited number of times, then automatic recovery will stop and a report will be sent to the host controller.

5. A heterogeneous dual-bus cooperative control system for a dual-arm robot, used to implement the heterogeneous dual-bus cooperative control method for a dual-arm robot as described in any one of claims 1-4, characterized in that, include: Frame; The arm mechanism is provided in two sets, symmetrically arranged on the frame. Each set of the arm mechanism consists of seven joint modules connected in series, and each joint module is equipped with a joint motor. The end effector unit is detachably mounted to the end output port of the joint module via an end interface flange; A binocular vision module is mounted on the frame and points to the common working area in front of the two sets of arm mechanisms; The control and wiring harness system adopts a heterogeneous dual-bus parallel topology, comprising a host controller, a first communication converter, an arm communication bus, a distribution board, a second communication converter, and an end communication bus, wherein: The host controller is connected to the arm communication bus via the first communication converter, and the power distribution board is electrically connected to the joint module. The host controller is connected to the end communication bus via the second communication converter, and the driver of the end execution unit is connected in series to the end communication bus.

6. The heterogeneous dual-bus cooperative control system for a dual-arm robot according to claim 5, characterized in that, The control and harness system also includes a power supply unit, which includes an arm power supply unit and an end power supply unit. The arm power supply unit is used to supply power to the joint module, and the end power supply unit is used to supply power to the end effector unit.

7. A heterogeneous dual-bus cooperative control system for a dual-arm robot according to claim 6, characterized in that, The power supply unit also includes an emergency stop switch for cutting off all drive power. One end of the emergency stop switch is connected in series with the output end of the arm power supply unit and the end power supply unit, and the other end of the emergency stop switch is connected to the distribution board and the end execution unit respectively.

8. A heterogeneous dual-bus cooperative control system for a dual-arm robot according to claim 5, characterized in that, The seven joint modules are connected in a daisy-chain manner on the arm communication bus.

9. A heterogeneous dual-bus cooperative control system for a dual-arm robot according to claim 5, characterized in that, The control and harness system also includes an observation fusion module, which acquires the arm joint angle of the joint module, the state quantity of the end effector, and the visual information of the binocular vision module in each acquisition cycle.

10. A heterogeneous dual-bus cooperative control system for a dual-arm robot according to claim 5, characterized in that, The arm communication bus has an arbitration segment rate of 1 Mbps and a data segment rate of 5 Mbps; the end communication bus is a serial bus with a rate of 1 Mbps.

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