CN105353726A - Special-purpose controller of electronic press, and control method - Google Patents

Abstract

The invention discloses a special controller and a control method for an electronic press-fitting machine, belonging to the field of equipment manufacturing. The controller of the present invention includes an ARM microcontroller and an FPGA, and the FPGA communicates with the ARM microcontroller through a high-speed bus; the ARM microcontroller is connected with an external sensor, an upper computer, etc. through an interface, and is used to realize high-speed collection and calculation of pressure data , real-time monitoring and judgment of the press-fitting process, pressure-displacement real-time display, communication and system management, etc.; FPGA is the core of motion control, which is connected with the servo driver through the servo interface module, and is used under the cooperation of the ARM microcontroller The built-in fuzzy neural network PID special motion control algorithm controls the speed, acceleration, torque and displacement of the servo motor to achieve precise pressing and positioning, and real-time monitoring and judgment through the touch screen to improve the quality of assembled products.

Description

A dedicated controller and control method for an electronic press-fitting machine

technical field

The invention relates to a special controller and a control method for a pressing machine, belonging to the field of equipment manufacturing.

Background technique

In the production process of parts, it is a common method to use a press machine for assembly, such as shaft assembly, pin assembly, etc. Traditional mechanical, hydraulic or gas-hydraulic booster press-fitting equipment cannot meet the needs of enterprises for high-precision assembly in industries such as auto parts, electronics, and home appliances because the press-fit force and press-fit displacement cannot be accurately controlled. The electronic press-fitting machine uses an AC servo motor as a power source, and cooperates with a precision planetary gear reducer to drive a screw to realize product press-fitting. Its structure is shown in Figure 1. The electronic press-fitting machine can not only produce accurate press-fit displacement and press-fit force, but also realize online monitoring and evaluation of the press-fit process, greatly improving the pass rate of products, which is the future development direction of press-fitting machines. At present, most domestic electronic press-fitting machines adopt the PLC+servo system mode. Although the cost of this kind of electronic press-fitting machine is low, due to the weak performance of PLC motion control, the optimal control of the press-fitting process cannot be achieved, and the process adaptability and flexibility are poor; Due to their strong research and development strength, foreign companies mostly adopt the controller mode integrating control, detection and servo drive, which has stable performance and perfect functions, but the price is expensive; whether it is a domestic or imported electronic press-fitting machine, the judgment of the press-fitting result is passed It is realized by monitoring the pressure of several specific displacements, and it is impossible to display the pressure-displacement curve in real time, let alone fully reflect the pressure-displacement changes in the press-fitting process, which may cause unqualified products to flow into the market, although additional expensive special Pressure-displacement monitor or PC-based special pressure-displacement monitoring software system, but it will undoubtedly greatly increase the cost of the enterprise.

Contents of the invention

In order to solve the shortcomings of the electronic press-fitting machine in the above-mentioned background technology, the present invention proposes a special controller for the electronic press-fitting machine, which is embedded with an optimized neural network control algorithm suitable for the press-fitting process of the press-fitting machine, which can not only realize accurate control of pressure and displacement, It can also realize the real-time monitoring of the press-fitting process and the real-time collection and display of the pressure-displacement curve, and the cost is low. The specific technical scheme is as follows:

A dedicated controller for an electronic press, comprising: a control module, an interface module, a storage module, and a sensor module; both the interface module and the storage module are connected to the control module; the sensor module is connected to the interface module The sensor module is used to collect the pressing information of the electronic pressing machine and transmit it to the control module through the interface module; the control module outputs control information after performing calculation and processing according to the pressing information and transmits it through the interface module For the electronic press-fitting machine; the interface module is also used to interact with peripheral equipment; the storage module is used to save the collected press-fit information data.

As a preferred technical solution, the control module includes an ARM microcontroller and an FPGA module, and the ARM microcontroller is connected to the FPGA module through a bus, and the FPGA module realizes the control by an embedded algorithm under the cooperation of the ARM microcontroller. Control of the press machine.

As a preferred technical solution, the embedded algorithm adopts a fuzzy neural network PID special motion control algorithm.

As a preferred technical solution, the ARM microcontroller adopts an ARM Cortex-M7 architecture chip.

As a preferred technical solution, the interface module includes an A/D interface, a D/A interface, a digital I/O, a servo interface, a USB interface, an Ethernet interface, and a touch screen interface; one end of the A/D interface is connected to an ARM microcontroller , the other end is connected to the sensor module, one end of the D/A interface is connected to the ARM microcontroller, and the other end is connected to the servo driver of the electronic pressing machine, one end of the servo interface is connected to the FPGA module, and the other end is connected to the servo driver, the USB interface One end and one end of the Ethernet interface are all connected to the ARM microcontroller, the other end of the USB interface and the other end of the Ethernet interface are connected to the host computer, one end of the touch screen interface is connected to the ARM microcontroller, and the other end Connect the touch screen, and the digital I/O is used to connect the switch button, the indicator light and the switch channel of the upper computer.

As a preferred technical solution, the sensor module includes a pressure sensor and a displacement sensor; the pressure sensor is installed on the lower mold, and the displacement sensor is installed on the upper mold.

As a preferred technical solution, the displacement sensor adopts a magnetic ruler or a grating ruler; the pressure sensor is a strain gauge sensor.

As a preferred technical solution, the storage module is FlashROM and SRAM.

Based on the above-mentioned controller, the present invention also proposes a control method of an electronic pressing machine, comprising the following steps:

Step 1. Connect with the host computer through the communication interface, use the programming software of the host computer or the touch screen to create the processing program, set the press-fitting parameters, the parameters include displacement, pressure, and select the appropriate judgment method; it can also be operated directly through the touch screen ;

Step 2, start press-fitting, the dedicated controller controls the servo motor to drive the telescopic rod to press down quickly, when the pressure sensor detects that the pressure head is in contact with the workpiece, the dedicated controller controls the press-fitting speed to decrease rapidly, and starts to press one workpiece into another in the workpiece;

Step 3, the pressing is completed, the pressure head rises to the initial position, and the touch screen displays the pressing result at the same time, and stores the detected pressure, displacement data and detection results.

As a preferred technical solution,

Step 2 also includes: the pressure sensor and the displacement sensor continuously collect signals to the control module. On the one hand, the control module uses the fuzzy neural network PID control algorithm to continuously adjust the motor speed and torque according to the pressure and displacement signals; Compare with the set parameters to judge whether the press fit is qualified, and at the same time, the pressure and displacement signals are displayed on the touch screen in real time in the form of curves. .

Compared with prior art, the beneficial effect of the present invention is:

(1) Using the embedded structure of ARM+FPGA, it can run complex special control algorithms and realize complex motion control that cannot be completed by PLC.

(2) It can realize the precise measurement and control of the pressure and displacement during the press-fitting process, and realize the real-time display and historical record of the pressure-displacement curve.

(3) There are various methods for judging the press-fitting results, with strong adaptability and good flexibility.

(4) Low equipment cost and strong competitiveness.

Description of drawings

Fig. 1 is the structural representation of the electronic press packing machine applied in the present invention;

Fig. 2 is a module block diagram of the present invention;

Fig. 3 is the fuzzy neural network PID principle structural diagram that the present invention adopts;

Fig. 4 is a schematic diagram of the fuzzy neural network PID control adopted in the present invention.

Marks in the figure: 1. Servo motor, 2. Reducer, 3. Telescopic rod, 4. Displacement sensor, 5. Pressure head, 6. Work piece, 7. Pressure sensor, 8. Special controller, 9. Servo driver, 10 . Electric control box, 11. Touch screen, 12. Rack, 13. Fixing seat.

detailed description

The technical solutions of the present invention will be described in detail below through embodiments in conjunction with the accompanying drawings.

As shown in Figure 1, servo motor 1, reducer 2, telescopic rod 3 and pressure head 5 constitute a press-fit power mechanism; servo motor 1 is installed on the frame 12 through fixing seat 13; dedicated controller 8 and servo driver 9 are installed together In the electric control box 10 (the electric control box is an iron box in the present invention), it is connected with the servo motor 1, the displacement sensor 4, the pressure sensor 7, the touch screen 11, etc. through a dedicated interface.

As preferably, described displacement sensor 4 can be grating ruler, also can adopt magnetic ruler, and grating ruler is a digital sensor, needs to pass to FPGA to decode through interface, and magnetic ruler is an analog quantity, needs to pass A/D channel input , specifically selected according to the user's precision requirements, if a grating ruler is used, it needs to be connected to the orthogonal coding interface of the special controller 8, and if a magnetic ruler is used, it needs to be connected to the analog special interface of the special controller 8. The pressure sensor is installed on the lower mold, the displacement sensor is installed on the upper mold, and the pressure sensor is a strain gauge sensor.

As shown in Fig. 2, the present invention takes the ARM Cortex-M7 architecture chip as the core, and uses SRAM and FlashROM as storage devices to form a microprocessor module. Specifically include: ARM microcontroller (such as STM32F7), FPGA module, A/D interface module, D/A interface module, digital I/O module, servo interface module, communication interface module, touch screen interface module, etc.

The ARM microcontroller communicates with buttons (start, reset, emergency stop buttons), sensors (comprising pressure sensors and Displacement sensor), upper computer or touch screen, etc., are used to realize high-speed collection and calculation of pressure data, real-time monitoring, judgment and display of pressure-displacement in the press-fitting process, as well as communication and system management with the upper computer, etc., and realize communication with the upper computer The cooperation of the FPGA module motion control function; the FPGA module connected to the ARM microcontroller through a high-speed bus is the core of the motion control, which is connected to the servo drive through the servo interface module, and through the cooperation of the ARM microcontroller. Embedded fuzzy neural network PID special motion control algorithm realizes the control of the speed, acceleration, torque and displacement of the servo motor, and realizes the reception and decoding of the position detection signals of the A and B phase displacement sensors of the grating scale.

In addition, USB interface, Ethernet interface, A/D interface, D/A interface, touch screen interface, digital I/O and servo interface etc. among the present invention form the external interface, are dedicated controller and external equipment (such as upper computer etc.) ), sensors, buttons, etc. for information exchange.

Some of the channels of the A/D interface module are used to connect to the pressure sensor, and some of the channels are used to connect to the acquisition of analog quantities such as a magnetic ruler displacement sensor (or a grating ruler displacement sensor).

The D/A interface module is used to output the analog voltage to the servo drive, so as to realize the special motion control algorithm of fuzzy neural network PID.

The digital I/O module is used to connect the switch button, the switch sensor, the indicator light and the switch channel of the upper computer.

The communication interface module includes a USB interface, an Ethernet interface, etc., and is used for communicating with an upper computer.

The servo interface module is a dedicated channel connecting the dedicated controller with the servo driver.

The touch screen interface is used to connect to the touch screen 11, and parameters can be set through the touch screen 11, and data information can also be displayed through the touch screen 11.

The microprocessor module uses the powerful data processing capability, floating-point computing capability and built-in A/D and D/A processing capabilities of the ARM chip to realize the pressure collection and the display and judgment of the pressure-displacement curve, and uses the built-in USB and Ethernet communication protocols The ability to communicate with the host computer and peripheral equipment, and complete the management and information display of the entire system.

The FPGA module is the core of motion control. It communicates with the ARM microcontroller at high speed through the bus, and receives the working data of the electronic press from the microcontroller, such as displacement, speed, acceleration and other parameters, and according to the built-in fuzzy neural network PID control algorithm Generate the corresponding control signal, control the movement of the servo motor, generate high-precision pressing force, and collect the displacement signal of the grating scale at the same time, decode the phase A and B, and send it to the ARM microcontroller.

As shown in Fig. 3 and Fig. 4, the specific implementation process of the fuzzy neural network PID special motion control algorithm in the present invention: the ARM micro-controller transmits the obtained indenter theoretical speed value to the FPGA module in real time, and the FPGA compares the theoretical value and the actual value For comparison, the optimal fuzzy rule is obtained through neural network training by using the high-speed computing capability of FPGA, and the fuzzy matrix is queried online through the fuzzy rule to adjust the parameters of the PID controller according to the deviation and differentiation of the deviation. And compared with the actual speed of the servo motor, the best drive signal of the servo motor is finally obtained to realize the control accuracy, response speed and stability of the electronic press machine.

Utilize special-purpose controller of the present invention to realize the method for press-packing machine control to comprise the following steps:

(1) Connect with the host computer through the communication interface, use the supporting programming software or the touch screen to create the processing program, set the press-fitting parameters, such as displacement, pressure range, etc., and select the appropriate judgment method (the judgment method is a common standard in the industry, including according to the position Detecting pressure, detecting position based on pressure and detecting pressure based on displacement); it can also be operated directly through the touch screen.

(2) Start pressing, the special controller controls the servo motor to drive the telescopic rod to press down quickly, when the pressure sensor detects that the pressure head is in contact with the workpiece, the special controller 8 controls the pressing speed to decrease rapidly, and starts to press a workpiece 6 into the In another workpiece 6.

(3) During the pressing process of step (2), the pressure sensor and the displacement sensor continuously collect signals to the controller. On the one hand, the controller continuously adjusts the motor speed and torque according to the pressure and displacement signals, using the fuzzy neural network PID control algorithm , On the other hand, compare the pressure and displacement signals with the set parameters to judge whether the press fit is qualified. At the same time, the pressure and displacement signals are displayed on the touch screen in real time in the form of curves, which is convenient for viewing.

(4) After the pressing is completed, the pressure head rises to the initial position, and the touch screen displays the pressing result at the same time, and stores the detected pressure, displacement data and detection results.

The above is only used to describe the technical solutions and specific embodiments of the present invention, and is not used to limit the protection scope of the present invention. It should be understood that any modification, improvement or equivalent Substitutions and the like will fall within the protection scope of the present invention.

Claims (10)

1. an electronics pressing machine nonshared control unit, is characterized in that, comprising: control module, interface module, memory module and sensor assembly; Described interface module is all connected with described control module with described memory module; Described sensor assembly is connected with described interface module; Described sensor assembly is for gathering press-fiting information and passing to described control module by described interface module of electronics pressing machine; Described control module exports control information according to press-fiting after information carries out calculation process, and passes to electronics pressing machine by described interface module; Described interface module is also for carrying out alternately with peripherals; Described memory module press-fits information data for what preserve collection.

2. a kind of electronics pressing machine nonshared control unit according to claim 1, it is characterized in that, described control module comprises ARM microcontroller and FPGA module, described ARM microcontroller connects FPGA module by bus, described FPGA module under the cooperation of described ARM microcontroller by embedded algorithm realization to the control of pressing machine.

3. a kind of electronics pressing machine nonshared control unit according to claim 2, is characterized in that, described embedded algorithm adopts the special motion control arithmetic of fuzzy neural network PID.

4. a kind of electronics pressing machine nonshared control unit according to claim 2, is characterized in that, described ARM microcontroller adopts ARMCortex-M7 framework chip.

5. a kind of electronics pressing machine nonshared control unit according to claim 2, it is characterized in that, described interface module comprises A/D interface, D/A interface, digital I/O, servo interface, USB interface, Ethernet interface and touch screen interface, described A/D interface one end connects ARM microcontroller, other end connecting sensor module, described D/A interface one end connects ARM microcontroller, the other end connects the servo-driver of electronics pressing machine, described servo interface one end connects FPGA module, the other end connects servo-driver, one end of described USB interface is all connected ARM microcontroller with one end of described Ethernet interface, the other end of described USB interface is all connected host computer with the other end of described Ethernet interface, described touch screen interface one end connects ARM microcontroller, the other end connects touch-screen, described digital I/O is used for connecting valve button, the switching value passage of pilot lamp and host computer.

6. a kind of electronics pressing machine nonshared control unit according to claim 1, it is characterized in that, described sensor assembly comprises pressure transducer and displacement transducer; Described pressure transducer is arranged on bed die, and institute's displacement sensors is arranged on mold.

7. a kind of electronics pressing machine nonshared control unit according to claim 6, is characterized in that, institute's displacement sensors adopts magnetic scale or grating scale; Described pressure transducer is strain-gauge transducer.

8. a kind of electronics pressing machine nonshared control unit according to claim 1, it is characterized in that, described memory module is FlashROM, SRAM.

9. a control method for electronics pressing machine, is characterized in that, comprises the steps:

Step 1, is connected with host computer by communication interface, and utilize the supporting programming software of host computer or touch-screen to create job sequence, arrange and press-fit parameter, described parameter comprises displacement, pressure, and selects suitable decision method; Also can directly be operated by touch-screen;

Step 2, starts to press-fit, and nonshared control unit controls driven by servomotor expansion link depressed fast, and when pressure transducer detects pressure head and absorption surface, nonshared control unit controls to press-fit speed to be reduced rapidly, starts a workpiece to be pressed in another workpiece;

Step 3, has press-fited, and pressure head rises to initial position, and touch-screen display simultaneously press-fits result, and the pressure detected, displacement data and testing result is stored.

10. the control method of a kind of electronics pressing machine according to claim 9, is characterized in that,

Step 2 also comprises: pressure transducer and the continuous collection signal of displacement transducer are to control module, control module is on the one hand according to pressure, displacement signal, Fuzzy Neural PID control algolithm is utilized constantly to adjust motor speed and torque, the parameter of pressure, displacement signal and setting contrasted on the other hand, whether qualified, pressure, displacement signal are shown to touch-screen in real time with curve form simultaneously if press-fiting with judgement.