Method for assigning node address and configuring resistance based on CAN communication network

Abstract

This invention relates to the field of automatic node address allocation and automatic terminal resistor configuration in the CAN communication network of collaborative robots, including steps S1, S2, S3, and S4. It addresses the shortcomings of manual or pre-set methods for allocating joint addresses and configuring terminal resistors. A method for automatically allocating CAN node addresses and configuring terminal resistors is designed, realizing automatic allocation of CAN network node addresses and automatic configuration of terminal resistors for collaborative robot joint devices. This achieves complete automation and intelligence, reduces operator difficulty, improves production efficiency, facilitates network setup and debugging, and enhances the maintainability of the robot equipment.

Description

Technical Field

[0001] This invention relates to the field of automatic node address allocation and automatic terminal resistor configuration in the CAN communication network of collaborative robots, specifically to a method for node address allocation and resistor configuration based on CAN communication network. Background Technology

[0002] Currently, most collaborative robots are 6-DOF (DoF), with redundant 7-DOF robots having 6 and 7 joints respectively. Bus communication between robot joints includes CAN, EtherCAT, Profinet, and EtherNet / IP. CAN bus networking is simple, has strong industrial anti-interference capabilities, and is the lowest cost, making it widely used in joint communication. As is well known, each node in a CAN network needs an independent and unique fixed address for normal network communication. Furthermore, the CAN bus uses a twisted pair of wires as the communication transmission line, and signal reflection at the end of the transmission line can negatively impact signal quality and anti-interference capabilities, necessitating physical impedance matching. Therefore, when deploying a CAN bus communication network, it is necessary to properly allocate CAN node addresses and configure terminating resistors for both ends of the device. Currently, a common address allocation method is to use DIP switches to physically assign a unique address to each joint. Another method is to pre-set a unique CAN address through another communication interface before connecting the joint to the CAN network, and then assemble it into the collaborative robot's CAN network. Common methods for configuring terminating resistors involve manually connecting external terminating resistors to the two terminal devices based on the physical placement of the CAN network nodes, or using DIP switches to connect the pre-installed terminating resistors on the joints to the CAN network. Collaborative robots have high IP protection ratings and stringent sealing requirements. Mechanical DIP switches negatively impact joint structure and protection design. Furthermore, methods of assigning addresses and configuring terminating resistors via DIP switches, presets through other communication ports, or manual external wiring affect production efficiency. The sealing characteristics of robot joints further increase the difficulty of maintenance with these configuration methods. Summary of the Invention

[0003] The purpose of this invention is to provide a non-circular mold with a pusher structure to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for CAN communication network node address allocation and resistor configuration, comprising the following steps: Step S1: After the system is powered on, the address of the master station joint is preset to the initial address by default, and the address output lines of all slave station joints output a high impedance state or a preset high level, so that the input address lines of each joint present the initial address value through the pull-up resistor; Step S2: The master joint or the current joint that has completed address configuration increments its own address value by 1 and outputs it as the configuration address to the input address line of the next level joint; Step S3: The next-level joint receives the configuration address and locks it as the communication address of this joint, and at the same time transmits the configuration address to the next-level joint through its own open-drain output stage; Step S4: The current joint reads its own output address line status through loopback to determine whether the level of the output address line is pulled high by the subsequent circuit. The joints of the collaborative robot are connected in a cascade manner, and each joint is connected in series via a CAN communication network, ultimately connecting to the main station controller.

[0005] Preferably, the automatic address allocation uses open-drain output address lines and pull-up input address lines, and the address is transferred by pulling up the pull-up resistor of the lower-level joint to achieve the address transfer.

[0006] Preferably, the terminating resistor configuration is controlled by an electronically controllable switch, which automatically selects whether to connect the terminating resistor according to the configuration strategy.

[0007] Preferably, the address allocation process includes: in the initial power-on state, all addresses are output as 111, and a delay is made to wait for all joints to complete the initial output state; the master station address is 000, and after the joint completes the configuration, the configuration address sent to the next level is the address of this joint plus 1.

[0008] Preferably, the output address is read in a loop to determine whether the joint is at the rearmost position in the physical location by checking whether the output address is pulled high by the pull-up resistor of the subsequent joint address. If so, the bus termination resistor is automatically closed.

[0009] Compared with the prior art, the beneficial effects of the present invention are: This paper addresses the shortcomings of manual or pre-set methods for allocating joint addresses and configuring terminating resistors. A method for automatically allocating CAN node addresses and configuring terminating resistors is designed to achieve automatic allocation of CAN network node addresses and automatic configuration of terminating resistors for collaborative robot joint devices. This realizes complete automation and intelligence, reduces operator difficulty, improves production efficiency, facilitates network setup and debugging, and enhances the maintainability of the robot equipment. Attached Figure Description

[0010] Figure 1 is a schematic diagram of the joint appearance of a 6-DOF collaborative robot.

[0011] Figure 2 shows a schematic diagram of the joint cascade and the related processing units of the CAN communication network in the joint.

[0012] Figure 3 is a schematic diagram of the automatic CAN address allocation and automatic terminating resistor configuration circuit inside the joint.

[0013] Figure 4 is a flowchart of the CAN address automatic allocation and terminating resistor automatic configuration software. Detailed Implementation

[0014] 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] Please see Figures 1 to 4 This invention provides a technical solution: Figure 1 is a schematic diagram of the joint appearance of a 6-DOF collaborative robot. Step S1: After the system is powered on, the address of the master joint is set to the preset initial address by default, and the address output lines of all slave joints output a high impedance state or a preset high level, so that the input address lines of each joint present the initial address value through the pull-up resistor; Step S2: The master joint or the current joint that has completed address configuration increments its own address value by 1 and outputs it as the configuration address to the input address line of the next level joint; Step S3: The next-level joint receives the configuration address and locks it as the communication address of this joint, and at the same time transmits the configuration address to the next-level joint through its own open-drain output stage; Step S4: The current joint reads its own output address line status through loopback to determine whether the level of the output address line is pulled high by the subsequent circuit. Six robot joints are sequentially distributed across the various joint positions of the robotic arm. A CAN communication network connects these joints in series. Most collaborative robot joints achieve IP66 or even IP68 protection ratings. Figure 2 shows a schematic diagram of the joint cascading and the related processing units of the CAN communication network within each joint. Joints are connected in a cascading manner, progressing step by step. Figure 3 shows a schematic diagram of the automatic CAN address allocation and automatic termination resistor configuration circuit within each joint. The output address lines are open-drain, while the input address lines are pull-up. The termination resistors are controlled by an electronically controllable switch, allowing selection of whether to connect them based on a strategy. Figure 4 is a flowchart of the CAN address allocation and automatic termination resistor configuration software. Initially, all address outputs are 111, and the master address is 000. After a joint completes configuration, the configuration address sent to the next level is the current joint address plus 1. Because the address is open-drain, a loopback function can be used to check if the output address is effectively pulled high by the pull-up resistor of the subsequent joint address, thus determining whether the joint is the last joint in its physical position. If it's the final joint, the automatic bus terminating resistor will close. Through the above process, the automatic allocation of CAN network addresses and the automatic configuration of terminating resistors are completed.

[0016] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for CAN communication network node address allocation and resistor configuration, characterized in that, Includes the following steps: Step S1: After the system is powered on, the address of the master station joint is set to the preset initial address by default. All slave station joints output high impedance or preset high level on their address output lines, so that the input address lines of each joint are presented as the initial address value through the pull-up resistors. Step S2: The master joint or the current joint that has completed address configuration increments its own address value by 1 and outputs it as the configuration address to the input address line of the next level joint; Step S3: The next-level joint receives the configuration address and locks it as the communication address of this joint, and at the same time transmits the configuration address to the next-level joint through its own open-drain output stage; Step S4: The current joint reads its own output address line status through loopback to determine whether the level of the output address line is pulled high by the subsequent circuit.

2. The method according to claim 1, characterized in that: The joints of the collaborative robot are connected in a cascade manner, and each joint is connected in series via a CAN communication network, ultimately connecting to the main station controller.

3. The method according to claim 1, characterized in that: The automatic address allocation uses open-drain output address lines and pull-up input address lines, and the address is transferred by pulling up the pull-up resistor of the lower-level joint to achieve the address transfer.

4. The method according to claim 1, characterized in that: The terminating resistor configuration is controlled by an electronically controllable switch, which automatically selects whether to connect the terminating resistor according to the configuration strategy.

5. The method according to claim 1, characterized in that: The address allocation process includes: in the initial power-on state, all addresses are output as 111, and there is a delay to wait for all joints to complete the initial output state; the master station address is 000, and after the joint completes the configuration, the configuration address sent to the next level is the address of this joint plus 1.

6. The method according to claim 1, characterized in that: By checking whether the output address is pulled high by the pull-up resistor of the subsequent joint address through loopback, it can be determined whether the joint is at the rearmost position in physical location. If so, the bus termination resistor is automatically closed.

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