A Servo System Based on Optical Fiber CAN Network

Abstract

The present invention discloses a servo system based on an optical fiber CAN network, comprising: a host computer, a first controller, a second controller, a first axis driver with multiple control signal terminals cascaded through optical fibers, and a second axis driver with multiple control signal terminals cascaded through optical fibers; and also comprising a CAN conversion module for realizing mutual conversion between optical signals and CAN messages. The present invention utilizes the optical fiber CAN conversion module to communicate between the host computer, the controller and the driver through optical fibers, thereby improving the anti-electromagnetic interference capability of the servo system CAN network. When a fault occurs, it can switch among multiple control modes to realize normal movement of the first axis driver and the second axis driver, thereby realizing redundant control of the servo system.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and more specifically, to a servo system based on an optical fiber CAN network. Background Art

[0002] Controller Area Network (CAN) is a mature industrial bus that is widely used in servo systems and other fields due to its high stability and high communication efficiency. At present, most CAN buses use twisted shielded pair cables as the networking transmission medium, and existing servo systems often have harsh electromagnetic environments, high voltages, strong magnetic fields, etc. In such complex control sites, CAN buses are easily affected by strong electromagnetic interference and cannot work properly. Optical fiber has the advantages of strong anti-electromagnetic interference ability and non-conductivity, which is suitable for systems with complex electromagnetic signals.

[0003] With the development of electronic manufacturing, robotics and other industries in recent years, the complexity of equipment has become increasingly higher, the number of servo drive axes required has gradually increased, and a single axis usually requires multiple motors to coordinate control. However, the existing industrial control field environment is complex, and the equipment is easily disturbed, affecting the normal operation of the system. In order to ensure the stable operation of the equipment, the system is required to isolate the fault in time after a fault occurs, which puts higher requirements on the reliability of the servo system. Summary of the invention

[0004] An object of the present invention is to provide a servo system redundant control method based on an optical fiber CAN network, in order to solve the problem of poor electromagnetic interference resistance of the CAN network in the prior art and to further improve the reliability of the servo system.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A servo system based on an optical fiber CAN network comprises: a host computer, a first controller, a second controller, a first axis driver with multiple control signal terminals cascaded through optical fibers, and a second axis driver with multiple control signal terminals cascaded through optical fibers;

[0007] The first control instruction end of the host computer is connected to the control instruction end of the first controller through an optical fiber, the first control signal end of the first controller is connected to the control signal end of the first axis driver located at the head end of the multiple first axis drivers cascaded through optical fibers through an optical fiber, and the control signal end of the first axis driver located at the end of the multiple first axis drivers cascaded through optical fibers is connected to the first control signal end of the second controller through an optical fiber;

[0008] The second control instruction end of the host computer is connected to the control instruction end of the second controller through an optical fiber, the second control signal end of the second controller is connected to the control signal end of the second axis driver located at the head end of the multiple second axis drivers cascaded through the optical fiber through an optical fiber, and the control signal end of the second axis driver located at the end of the multiple second axis drivers cascaded through the optical fiber is connected to the second control signal end of the first controller through an optical fiber.

[0009] Preferably, it also includes a CAN conversion module for realizing mutual conversion between optical signals and CAN messages.

[0010] Preferably, the host computer, the first controller, the second controller, the plurality of first axis drivers and the plurality of second axis drivers all include a plurality of optical fiber CAN conversion modules.

[0011] Preferably, it is characterized in that, in the servo system,

[0012] The CAN message of the sending end is converted into an optical signal by the optical fiber CAN conversion module and transmitted to the receiving end through the optical fiber;

[0013] The receiving end converts the optical signal into a CAN message through the optical fiber CAN conversion module for reception.

[0014] Preferably, the servo system has multiple control modes, and the multiple control modes include: a first control mode, the host computer controls a first controller and a second controller, the first controller controls a plurality of first axis drivers, and the second controller controls a plurality of second axis drivers.

[0015] Preferably, the multiple control modes also include:

[0016] In the second control mode, the host computer controls the first controller, and the first controller controls a plurality of first axis drivers and a plurality of second axis drivers respectively.

[0017] Preferably, the multiple control modes also include:

[0018] In the third control mode, the host computer controls the second controller, and the second controller controls the plurality of first axis drivers and the plurality of second axis drivers respectively.

[0019] Preferably, the multiple control modes also include:

[0020] In the fourth control mode, the host computer controls the second controller, the second controller controls a plurality of first axis drivers, and the host computer controls the first controller, the first controller controls a plurality of second axis drivers.

[0021] Preferably, the host computer is used to determine whether a fault occurs, and to switch among the multiple control modes when a fault is determined to occur, so as to achieve normal movement of the first axis driver and the second axis driver.

[0022] The beneficial effects of the present invention are as follows:

[0023] The present invention utilizes the optical fiber CAN conversion module to communicate between the host computer, the controller and the driver through optical fiber, thereby improving the anti-electromagnetic interference capability of the servo system CAN network. When a fault occurs, it can switch between multiple control modes to achieve normal movement of the first axis driver and the second axis driver, thereby achieving redundant control of the servo system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A system block diagram showing a specific embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0026] A servo system based on an optical fiber CAN network comprises: a host computer, a first controller, a second controller, a first axis driver with multiple control signal terminals cascaded through optical fibers, and a second axis driver with multiple control signal terminals cascaded through optical fibers;

[0027] The first control instruction end of the host computer is connected to the control instruction end of the first controller through an optical fiber, the first control signal end of the first controller is connected to the control signal end of the first axis driver located at the head end of the multiple first axis drivers cascaded through optical fibers through an optical fiber, and the control signal end of the first axis driver located at the end of the multiple first axis drivers cascaded through optical fibers is connected to the first control signal end of the second controller through an optical fiber;

[0028] The second control instruction end of the host computer is connected to the control instruction end of the second controller through an optical fiber, the second control signal end of the second controller is connected to the control signal end of the second axis driver located at the head end of the multiple second axis drivers cascaded through the optical fiber through an optical fiber, and the control signal end of the second axis driver located at the end of the multiple second axis drivers cascaded through the optical fiber is connected to the second control signal end of the first controller through an optical fiber.

[0029] Preferably, it also includes a CAN conversion module for realizing mutual conversion between optical signals and CAN messages.

[0030] Preferably, the host computer, the first controller, the second controller, the plurality of first axis drivers and the plurality of second axis drivers all include a plurality of optical fiber CAN conversion modules.

[0031] Preferably, it is characterized in that, in the servo system,

[0032] The CAN message of the sending end is converted into an optical signal by the optical fiber CAN conversion module and transmitted to the receiving end through the optical fiber;

[0033] The receiving end converts the optical signal into a CAN message through the optical fiber CAN conversion module for reception.

[0034] Preferably, the servo system has multiple control modes, and the multiple control modes include: a first control mode, the host computer controls a first controller and a second controller, the first controller controls a plurality of first axis drivers, and the second controller controls a plurality of second axis drivers.

[0035] Preferably, the multiple control modes also include:

[0036] In the second control mode, the host computer controls the first controller, and the first controller controls a plurality of first axis drivers and a plurality of second axis drivers respectively.

[0037] Preferably, the multiple control modes also include:

[0038] In the third control mode, the host computer controls the second controller, and the second controller controls the plurality of first axis drivers and the plurality of second axis drivers respectively.

[0039] Preferably, the multiple control modes also include:

[0040] In the fourth control mode, the host computer controls the second controller, the second controller controls a plurality of first axis drivers, and the host computer controls the first controller, the first controller controls a plurality of second axis drivers.

[0041] Preferably, the host computer is used to determine whether a fault occurs, and to switch among the multiple control modes when a fault is determined to occur, so as to achieve normal movement of the first axis driver and the second axis driver.

[0042] A specific embodiment

[0043] like Figure 1 As shown,

[0044] A servo system based on an optical fiber CAN network comprises a host computer including an optical fiber CAN conversion module, a controller A including the optical fiber CAN conversion module, a controller B including the optical fiber CAN conversion module, A-axis drivers A1 to An including the optical fiber CAN conversion module, B-axis drivers B1 to Bn including the optical fiber CAN conversion module and optical fibers.

[0045] The optical fiber CAN conversion module of the host computer is connected to the optical fiber CAN conversion module of the controller A through optical fiber, the optical fiber CAN conversion module of the controller A and the optical fiber CAN conversion module of the A-axis driver A1 are connected through optical fiber, the optical fiber CAN conversion modules of the A-axis drivers A1 to An are cascaded through optical fiber, and the optical fiber CAN conversion module of the A-axis cascade end driver An and the optical fiber CAN conversion module of the controller B are connected through optical fiber; the optical fiber CAN conversion module of the host computer and the optical fiber CAN conversion module of the controller B are connected through optical fiber, the optical fiber CAN conversion module of the controller B and the optical fiber CAN conversion module of the B-axis driver B1 are connected through optical fiber, the optical fiber CAN conversion modules of the B-axis drivers B1 to Bn are cascaded through optical fiber, and the optical fiber CAN conversion module of the B-axis cascade end driver Bn and the optical fiber CAN conversion module of the controller A are connected through optical fiber.

[0046] The function of the fiber optic CAN conversion module is to realize the mutual conversion between optical signals and CAN messages. The CAN messages at the sending end are converted into optical signals through the fiber optic CAN conversion module, and then transmitted through optical fibers. The receiving end converts the optical signals into CAN messages through the fiber optic CAN conversion module for reception. The fiber optic CAN conversion module is used to communicate between the host computer, controller and driver through optical fibers, which improves the anti-electromagnetic interference capability of the servo system CAN network.

[0047] The main function of the servo system is to control the movement of the A-axis and the B-axis through the controller A and the controller B. In the above-mentioned optical fiber CAN network, through different combinations of the host computer, controller A, controller B, drivers A1 to An, and drivers B1 to Bn, a complete A-axis control system and a B-axis control system are formed, which can realize four control modes of the servo system:

[0048] Control mode 1: The host computer, controller A and drivers A1 to An form the A-axis control system, and the host computer, controller B and drivers B1 to Bn form the B-axis control system;

[0049] Control mode 2: The host computer, controller A and drivers A1 to An form the A-axis control system, and the host computer, controller A and drivers B1 to Bn form the B-axis control system.

[0050] Control mode three: the host computer, controller B and drivers A1 to An form the A-axis control system, and the host computer, controller B and drivers B1 to Bn form the B-axis control system;

[0051] Control mode 4 is: the host computer, controller B and drivers A1 to An form the A-axis control system, and the host computer, controller A and drivers B1 to Bn form the B-axis control system.

[0052] When a fault occurs, the servo system switches between the above four control modes to ensure that the A-axis and the B-axis can continue to move normally, thus realizing redundant control of the servo system.

[0053] Take control mode 1 and control mode 2 as examples to explain the working principle:

[0054] The host computer transmits the A-axis control command to the fiber CAN conversion module of controller A through the fiber CAN conversion module; controller A accepts the A-axis control command, and transmits the A-axis driver control information processed by the A-axis control algorithm to the fiber CAN conversion module of driver A1 through the fiber CAN conversion module; driver A1 accepts the A-axis driver control information, and transmits the A-axis driver control information between the cascade drivers A1 to An through the fiber CAN conversion module to control the A-axis movement; the cascade drivers A1 to An transmit the A-axis driver operation status to the fiber CAN conversion module of controller A through the fiber CAN conversion module; controller A accepts the A-axis driver operation status, participates the A-axis driver operation status in the A-axis control algorithm operation, and transmits the A-axis system control status to the fiber CAN conversion module of the host computer through the fiber CAN conversion module; the host computer accepts the A-axis system control status, and displays it on the control interface after processing. The above is the A-axis control system that controls the A-axis movement through controller A, and the B-axis control system that controls the B-axis movement through controller B can be obtained in the same way. The two constitute the control mode 1 of the servo system. The host computer, controller and driver communicate through optical fiber, which improves the anti-electromagnetic interference capability of the servo system CAN network.

[0055] When controller B fails, it can be switched to control mode 2. At this time, the A-axis control system remains unchanged, and the B-axis is controlled by controller A. The host computer transmits the B-axis control command to controller A through the optical fiber CAN conversion module, and performs the B-axis control algorithm calculation in controller A. Controller A transmits the B-axis driver control information processed by the B-axis control algorithm to driver Bn through the optical fiber CAN conversion module; driver Bn transmits the B-axis driver control information between cascade drivers Bn and B1 through the optical fiber CAN conversion module to control the movement of the B-axis; cascade drivers Bn to B1 transmit the B-axis driver operating status to controller A through the optical fiber CAN conversion module; controller A transmits the B-axis system control status to the host computer through the optical fiber CAN conversion module for display. This constitutes a B-axis control system that controls the movement of the B-axis through controller A. After a failure occurs, control mode 1 is switched to control mode 2, ensuring that the A-axis and B-axis continue to move normally, and realizing redundant control of the servo system.

[0056] This embodiment uses the optical fiber CAN conversion module to communicate between the host computer, controller and driver through optical fiber, and builds a servo system optical fiber CAN network, realizes redundant control of the servo system, and improves the electromagnetic interference resistance and system reliability of the servo system CAN network.

[0057] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A servo system based on optical fiber CAN network, characterized in that: include: A host computer, a first controller, a second controller, a first axis driver to which a plurality of control signal terminals are cascaded through optical fibers, and a second axis driver to which a plurality of control signal terminals are cascaded through optical fibers; The first control instruction end of the host computer is connected to the control instruction end of the first controller through an optical fiber, the first control signal end of the first controller is connected to the control signal end of the first axis driver located at the head end of the multiple first axis drivers cascaded through optical fibers through an optical fiber, and the control signal end of the first axis driver located at the end of the multiple first axis drivers cascaded through optical fibers is connected to the first control signal end of the second controller through an optical fiber; The second control instruction end of the host computer is connected to the control instruction end of the second controller through an optical fiber, the second control signal end of the second controller is connected to the control signal end of the second axis driver located at the head end of the multiple second axis drivers cascaded through the optical fiber through an optical fiber, and the control signal end of the second axis driver located at the end of the multiple second axis drivers cascaded through the optical fiber is connected to the second control signal end of the first controller through an optical fiber.

2. The servo system based on optical fiber CAN network according to claim 1 is characterized in that: It also includes a CAN conversion module for realizing mutual conversion between optical signals and CAN messages.

3. The servo system based on optical fiber CAN network according to claim 2 is characterized in that: The host computer, the first controller, the second controller, the plurality of first axis drivers and the plurality of second axis drivers all include a plurality of optical fiber CAN conversion modules.

4. The servo system based on optical fiber CAN network according to claim 3 is characterized in that: In the servo system, The CAN message of the sending end is converted into an optical signal by the optical fiber CAN conversion module and transmitted to the receiving end through the optical fiber; The receiving end converts the optical signal into a CAN message through the optical fiber CAN conversion module for reception.

5. The servo system based on optical fiber CAN network according to claim 1, characterized in that: The servo system has multiple control modes, and the multiple control modes include: a first control mode, the host computer controls a first controller and a second controller, the first controller controls a plurality of first axis drivers, and the second controller controls a plurality of second axis drivers.

6. The servo system based on optical fiber CAN network according to claim 5, characterized in that: The multiple control modes also include: In the second control mode, the host computer controls the first controller, and the first controller controls a plurality of first axis drivers and a plurality of second axis drivers respectively.

7. The servo system based on optical fiber CAN network according to claim 5, characterized in that: The multiple control modes also include: In the third control mode, the host computer controls the second controller, and the second controller controls the plurality of first axis drivers and the plurality of second axis drivers respectively.

8. The servo system based on optical fiber CAN network according to claim 5, characterized in that: The multiple control modes also include: In the fourth control mode, the host computer controls the second controller, the second controller controls a plurality of first axis drivers, and the host computer controls the first controller, the first controller controls a plurality of second axis drivers.

9. The servo system based on optical fiber CAN network according to claim 8, characterized in that: The host computer is used to determine whether a fault occurs, and to switch among the multiple control modes when a fault is determined to occur, so as to achieve normal movement of the first axis driver and the second axis driver.

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