CN202512415U - ARM platform-based step-motor closed loop control system - Google Patents

Abstract

The utility model discloses a stepping motor closed-loop control system based on an ARM platform, and the system is a distributed control system. The host part is composed of a PC computer, and the stepper motor control part is composed of ARM7 microprocessor as the core. The host part is mainly responsible for user interface display and command control. The stepper motor control part realizes one stepper motor drive, grating ruler input signal interpretation, limit switch signal input control, jog control and PC computer real-time communication. Real-time communication between the PC computer and the stepper motor controller is carried out through the CAN bus interface.

Description

Closed-loop control system of stepper motor based on ARM platform

technical field

The utility model relates to a closed-loop control system of a stepping motor based on an ARM platform. Especially related to a real-time network embedded stepper motor closed-loop control system based on CAN network connection

Background technique

At present, stepper motors are generally used for drive control when the work mobile station is controlled. One of the main advantages of the stepper motor is that it can guarantee a certain control accuracy in the open-loop system, but the open-loop system also has some disadvantages: it is impossible to know whether the stepper motor fails in the constant speed stage of point movement and the speed-up stage of starting. Step, whether to overstep at the end of the step, and the speed change caused by the load change, especially when the load torque is large and there is an impact phenomenon, the phenomenon of step loss and step loss is very prominent, so that the stepper motor The application of open-loop control is affected to some extent. the

In order to realize the accurate positioning of the working mobile platform, the closed-loop control using the grating ruler as the position detection link is adopted. The fundamental method is that the grating ruler feeds back the detected position pulse of the working platform to the controller, and the controller according to the detected actual The displacement state is used to adjust the input pulse number and frequency in real time, so that the stepping motor is stable in the normal operation state, and the actual position is consistent with the command position, so as to meet the requirements of precise positioning. the

Utility model content

In order to achieve the above object, the utility model proposes a stepper motor closed-loop control system based on the ARM platform, including a host part and a stepper motor control part; the host part is composed of a PC computer, which is mainly responsible for user interface display and command control; The stepper motor control part is composed of ARM7 microprocessor as the core, including USB-CAN bus converter, motor controller, power supply, electric platform, output power adjustable device and attenuation mode adjustable device; the stepper motor control part Realize one stepper motor drive, grating ruler input signal interpretation, limit switch signal input control, jog control and PC computer real-time communication; ARM microprocessor and motor driver chip use isolation circuit; PC computer and stepper motor controller Communicate in real time through the CAN bus interface. the

The motor controller is mainly equipped with ARM microprocessor, stepping motor control circuit, photoelectric isolation circuit, system reset circuit, memory circuit, CAN bus interface circuit, USB interface circuit, RS232 interface circuit, wireless interface circuit, feedback control circuit , a limit control circuit and a synchronous signal output circuit; the electric platform is connected with a motor controller, and it is mainly provided with a stepper motor, a mobile platform, a grating ruler and a limit switch; the PC computer passes through a USB-CAN bus converter It is connected with the motor controller, and the power supply is electrically connected with the motor controller; the output power adjustable device and the attenuation mode adjustable device are connected with the motor controller for linearly adjusting the output power and setting different attenuation modes. the

Further, the stepper motor control circuit adopts the ARM microprocessor AT91SAM7X256, and according to the control command transmitted in real time by the supporting software on the PC computer, calls the operation plan that includes parameters such as address, direction, speed, stroke, cycle, resolution, etc., accurately Control the movement of the stepper motor. the

Further, the motor controller adopts THB6064H as the motor drive chip, and the running direction, speed, and subdivision mode of the stepper motor can be set through the supporting software on the PC computer, and 2/8/10/16/20/32/40 /64 and other multi-level subdivision modes, so as to realize precise electronically controlled movement with minimal vibration at low speed and higher positioning accuracy. the

Further, the isolation circuit of the stepping ARM microprocessor and the motor drive chip adopts TLP2530 and TLP521-4, thereby realizing the isolation of the weak current part and the strong current part of the system, achieving the purpose of suppressing system noise and eliminating the interference of the ground loop. the

Furthermore, in order to prevent the mobile platform from moving out of bounds when it is working, limit switches are set at the extreme positions on both sides of the mobile platform guide rail, which can automatically trigger a signal to the stepper motor controller when the platform exceeds the range of motion, so that it can respond in real time and stop motor movement. the

Further, the motor controller communicates with the PC computer in real time through the USB-CAN bus converter, and the converter circuit uses STM32F103RBT6 as the main control protocol conversion chip, and can also be cascaded with other motor controllers through the CAN bus interface to form a set of The stepper motor control system with precise and controllable multi-dimensional position can have a maximum dimension of 15 dimensions. the

Further, the stepper motor closed-loop control system based on the ARM microprocessor platform is also provided with two jog control buttons used to control the motor moving direction, and is designed with a debounce circuit, which can be manually performed without inputting the operation plan. Positioning with relative accuracy requirements. the

Further, the wireless interface circuit adopts the ZIGBEE mode, and the parameters of the motor controller can be set through wireless data transmission. The main control chip of the circuit adopts CC2430, and the wireless interface mode can also use other frequency wireless interface modes. the

Further, the stepper motor control part is also designed with an adjustable output power device and an adjustable attenuation mode device, which can respectively set the output power and attenuation mode, so that the system can be fully utilized under different application conditions. application; the motor controller also has a flashing indicator light indicating whether the system is working normally or not. the

Furthermore, the synchronization signal output circuit can be used to connect with other devices to synchronize the work of other devices, so that the whole system has a wider application field. the

Compared with prior art, the beneficial effect of the utility model is:

The control system of the utility model adds the grating ruler as the closed-loop control of the position detection link. The fundamental method is that the grating ruler feeds back the detected position pulse of the working platform to the controller. Adjust the input pulse number and frequency in real time to make the stepping motor stable in the normal running state, and make the actual position consistent with the command position, so as to meet the requirements of precise positioning.

The control system of the utility model also adds the CAN network connection function, which can communicate with the remote machine, and greatly improves the communication distance, and can realize multi-level interconnection control more flexibly, so that the application of the system can be more extensive . the

In order to prevent the mobile platform from moving out of bounds when it is working, limit switches are set at the extreme positions on both sides of the guide rail of the mobile platform, which can automatically trigger a signal to the stepper motor controller when the platform exceeds the range of motion, so that it can respond in real time and stop the motor movement . the

Equally, the utility model has also adopted two inching control buttons that can manually control the moving position of the mobile station. Positioning with relative accuracy requirements can be carried out manually without entering a traversing profile. the

And because use ARM microprocessor to be the core of circuit control system, sufficient space in the ARM microprocessor can reserve certain program space and external interface for other functions on this system, has greatly enhanced the flexibility of the present utility model. scalability. the

Description of drawings

Fig. 1 is the block diagram of circuit principle of the present utility model;

Fig. 2 is the electrical connection circuit diagram of each port part of the ARM microprocessor of the utility model embodiment;

Fig. 3 is the ARM microprocessor and the CAN bus interface circuit diagram of the utility model embodiment;

Fig. 4 is the ARM microprocessor and USB interface circuit diagram of the utility model embodiment;

Fig. 5 is the ARM microprocessor of the utility model embodiment and RS232 interface circuit diagram;

Fig. 6 is the ARM microprocessor and wireless interface circuit diagram of the utility model embodiment;

Fig. 7 is the stepper motor control circuit diagram of the utility model embodiment;

Fig. 8 is the photoelectric isolation circuit diagram of the utility model embodiment;

Fig. 9 is a synchronous signal output circuit diagram of the utility model embodiment;

Fig. 10 is the upper schematic diagram of the utility model embodiment;

Fig. 11 is the front schematic view of the utility model embodiment;

Fig. 12 is a schematic diagram of the reverse side of the embodiment of the utility model.

The components in Figure 1-11 are marked as follows:

1. ARM microprocessor; 2. CAN bus interface circuit; 3. USB interface circuit; 4. RS232 interface circuit; 5. Wireless interface circuit; 6. System reset circuit; 7. Memory circuit; 8. Synchronization signal output circuit; 9. Limit control circuit; 10. Flashing indicator light; 11. Stepping motor control circuit; 12. Photoelectric isolation circuit; 13. Output power adjustable device; 14. Attenuation mode adjustable device; 15 Jog control button; 16 . Stepping motor interface; 17. Limit switch interface; 18. Grating ruler interface; 19. Stepping motor; 20. Mobile platform; 21. Limit switch; 22. Grating ruler; 23 Motor controller; 24. PC computer ; 25. USB-CAN bus converter; 26. Power supply.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail:

As shown in the schematic circuit diagram of Figure 1, ARM microprocessor 1 and CAN bus interface circuit 2, USB interface circuit 3, RS232 interface circuit 4, wireless interface circuit 5, system reset circuit 6, memory circuit 7, synchronization signal output circuit 8. Limit control circuit 9, flashing indicator light 10, stepper motor control circuit 11, jog control button 15, limit switch interface 17 and grating ruler interface 18 are electrically connected;

The stepper motor control circuit 11 is electrically connected with the photoelectric isolation circuit 12, the output power adjustable device 13, the attenuation mode adjustable device 14 and the stepper motor interface 16;

Mobile station 20 is fixedly connected with stepper motor 19, limit switch 21 and grating ruler 22; Stepper motor 19 is connected with stepper motor interface 16 cables; Limit switch 21 is connected with limit switch interface 17 cables; Grating ruler 22 and Grating ruler interface 18 cable connection;

USB-CAN bus converter 25 is connected with CAN bus interface circuit 2 cables; PC computer 24 is connected with USB-CAN bus converter 25 cables;

Motor controller 23 is connected with power supply 26;

After inputting on the software interface of the PC computer 24 the operating scheme that needs to be operated and controlled and includes parameters such as address, direction, speed, stroke, cycle, resolution, etc., the ARM microprocessor 1 first stores this scheme parameter through the memory circuit 7 , so that after the PC computer 24 is disconnected, it can still run according to the parameters of this scheme, the ARM microprocessor 1 will output the control command to the stepping motor control circuit 11, and the latter will output the control command to the stepping motor control circuit 11 through the photoelectric isolation circuit 12. Into the motor interface 16, thereby driving the stepper motor 19 to work to make the mobile platform 20 move to the position set in the operation plan.

This system uses the grating ruler 22 as the position detection link of the displacement of the mobile platform. The output of the grating ruler 22 is an electric signal. When the moving ruler moves a grating pitch, the output electric signal changes a period. It measures the relative displacement between the moving ruler and the fixed inauguration by measuring the signal change period. The output signals of the currently used grating ruler 22 generally have two forms, one is 2 channels of square wave signals with a phase angle difference of 90°, and the other is 4 channels of sinusoidal signals with a phase difference of 90° in sequence. This system is designed for the grating ruler 22 that outputs square wave signals, and for the grating ruler that outputs sine wave signals, it can be transformed into square wave signal output after shaping. The grating scale 22 outputting the square wave has three electric signals of A phase, B phase and Z phase, the A phase signal is the main signal, and the B phase is the auxiliary signal. The two signal periods are the same, both are W, and the phase difference is 90°. The signal is input to the ARM microprocessor 1 through the grating ruler interface 18, and the measurement and processing of this signal need to go through: filtering and rectification, fine resolution, counting, and data exchange with the system. The ARM microprocessor 1 compares and judges the data obtained from the grating ruler 22 with the program parameters set by the PC computer 24, and performs error correction, thereby realizing precise closed-loop control of the moving position. the

The utility model also designs an output power adjustable device 13 and an attenuation mode adjustable device 14 on the control of the electric mobile station. They can respectively set the size of the output power and the attenuation mode, so that the system can be used under different application conditions. be fully applied. the

The utility model has two far and near limit switches 21, which is equivalent to setting a moving range for the electric control mobile station. When the moving position reaches any one of the far and near two limit switches 20, the limit switch 21 will A position signal is output to the ARM microprocessor 1 via the limit switch interface 17 . This means that the mobile station has moved to the extreme value of one side of the position range, and the mobile station can no longer move in this direction, but can only move in the opposite direction. This will effectively ensure the validity of the mobile position of the electronically controlled mobile station. the

The utility model is also designed with a cascading function, which can be cascaded with other motor controllers through the CAN bus interface to form a stepper motor control system with precise and controllable multi-dimensional positions, and its maximum dimension can be 15 dimensions. the

The utility model has designed two inching control keys 15 that can manually control the moving position of the mobile station. Positioning with relative accuracy requirements can be carried out manually without entering a traversing profile. the

Because the ARM microprocessor is used as the core of the circuit control system, the sufficient space in the ARM microprocessor can reserve a certain program space and external interface for other functions on the system, which greatly enhances the expandability of the utility model sex. the

It should be pointed out that any modification made according to the specific embodiments of the present utility model shall not deviate from the spirit of the present utility model and the scope described in the claims. the

Claims (8)

1. Closed-Loop Control of Stepping Motor system based on the ARM platform; Native system is a distributed control system; Host machine part is made up of a PC computer, mainly is responsible for user interface demonstration and order control, and the step motor control part is that core is formed by the ARM7 microprocessor; It is characterized in that: the step motor control part realizes that then one tunnel step motor drive, grating chi input signal are understood, the limit switch signal input is controlled, crawl is controlled and PC computer real-time Communication for Power; ARM microprocessor and motor drive ic adopt buffer circuit; Carry out real-time Communication for Power through the CAN EBI between PC computer and the controllor for step-by-step motor.

2. the Closed-Loop Control of Stepping Motor system based on the ARM platform as claimed in claim 1 is characterized in that: described stepping motor control circuit adopts ARM microprocessor AT91SAM7X256.

3. like the described Closed-Loop Control of Stepping Motor system based on the ARM platform of claim 1, it is characterized in that: described step motor drive chip adopts THB6064H.

4. the Closed-Loop Control of Stepping Motor system based on the ARM platform as claimed in claim 1 is characterized in that: the buffer circuit of described stepping ARM microprocessor and motor drive ic adopts TLP2530 and TLP521-4.

5. the Closed-Loop Control of Stepping Motor system based on the ARM platform as claimed in claim 1 is characterized in that: described USB-CAN bus converter circuit adopts STM32F103RBT6.

6. the Closed-Loop Control of Stepping Motor system based on the ARM platform as claimed in claim 1; It is characterized in that: described limit switch signal input is controlled to be the limit switch of transfer table guide rail both sides extreme position; Can when platform exceeds range of movement, automatic trigger pip give controllor for step-by-step motor, make its real-time response and stop motor movement.

7. the Closed-Loop Control of Stepping Motor system based on the ARM platform as claimed in claim 1 is characterized in that: described crawl is controlled to be crawl control button, can under the prerequisite of not importing operating scheme, manually carry out the location that relative accuracy requires.

8. the Closed-Loop Control of Stepping Motor system based on the ARM platform as claimed in claim 1 is characterized in that: the step motor control part also is designed with wireless interface circuit, and its circuit adopts CC2430.

Images