The principle and function of any bus grinding wheel dresser based on PMAC motion controller are analyzed, and with the help of PMAC drive interface.
Database Pcomm32PRO and executive program PEwin32PRO development tool, with the support of PLC program, develop the user software of grinding wheel dresser.
Realizing the fast function of control panel can reduce its own error by optimizing PID parameters. Experiments show that the system can realize the NC forming of grinding wheel.
Grinding wheel modification.
[Keywords:] Forming grinding wheel; Numerical control technology; Error adjustment
PMAC (Programmable Multi-axis Controller)
Programmable multi-axis controller, manufactured by DeltaTau Company, USA, 1990.
The motion controller on PC platform launched in 2000 is a set of motion.
Axis control, PLC control and multifunctional motion data acquisition.
Control products. Grinding is one of the finishing methods of parts, including
Time is also the last process of precision machining, which directly determines the quality of the workpiece.
In this paper, PMAC is used to control the high-precision modification of forming grinding wheel.
Transform key technologies and realize digital control.
Design of NC system for forming grinding wheel dresser
Digital control principle of bus transformation of forming grinding wheel
Figure 1 is the structural block diagram of the grinding wheel busbar shaper.
X, Y direction drive and positioning group drive are controlled by numerical control program.
Modify the shape with a diamond pen grinding wheel. The mother of numerical control system design
The driving and positioning components in X and Y directions are controlled by lines to form molding sand.
The bus bar of the wheel is trimmed into any required shape. X, y direction.
X and Y coordinates obtained by driving the positioning part of the positioning assembly.
Mark, can be fed back to the CNC system, correct the x and y direction.
Position error.
As can be seen from fig. 2, the motion controller is connected with the PC and the control panel.
Then, the special control program written in VC++ language is stored on the PC.
Software, you can read CNC programs. Settings on the control panel.
X/Y axis selection, forward/reverse direction movement, forward rotation of spindle motor,
And buttons such as fast door-to-door feed speed. , can realize the control of machine tools.
Direct control. The CNC control system is based on PMAC motion controller.
Special control system developed for the foundation.
Mechanical control of 1.2 forming grinding wheel based on PMAC motion controller
control system design
The control system adopts an open numerical control system, and the main control department
Ordinary PC is another choice. The principle of hardware selection for CNC system is
On the premise of meeting the function and accuracy requirements of machine tools, high reliability is guaranteed.
Reliability and compatibility. The hardware of CNC system of machine tool includes: spindle drive.
Motive, servo driver, PMAC motion controller, host.
Spindle drive motor provides an important tool for grinding wheel bus processing.
Working parameters of NC machining (spindle speed S) and driving force, etc. primary
The shaft motor is YLgo-4, Chaoyang single-phase asynchronous motor, with technical parameters.
Digital: power 750W, voltage 22OV, speed 1400 r/min, current.
5.2A。
Servo drive device provides feed speed f, straight line for grinding wheel dressing.
The machining accuracy and efficiency are determined. The system adopts Yaskawa servo motor.
The machine and the driver are the servo drives of the X axis and Y axis of the system,
It has the advantages of short adjustment time, high speed, high precision and stable operation.
Advantages. The x-axis and y-axis are selected from E-N series SG-
MAH-O4AA4 1 servo motor and SGDM-04ADA
Servo driver, technical parameters: rated power 0.4kw, voltage 200.
The rated speed is 3000 rpm, and the maximum speed is 5000 rpm.
The torque is 1.27 Nm, and the instantaneous maximum torque is 3.82 Nm.
The control core PMAC motion controller includes PMACZA-
PC 104, ACC-ZP high-speed digital communication expansion board, ACGI+
ACC-2 wiring board, ACC-34AE, etc.
The main parameters of PMACZA-PC 104 are: four-channel SV pulse.
+direction control servo, and can also output 12 nOV simulation; each
This channel provides two zeros 1 limit; PClo4 bus, 4oMHz
DSP control; RS232 serial communication.
ACC-ZP high-speed digital communication expansion board: 8 16-bit double terminals.
Mouth hammer; Digital 1/0 board, 1/0 expansion board; In addition, 16 sets are provided.
SV: custom 1/0 point and 2 handwheel channels.
ACC- 1+ACC-2 terminal board: provides four pulses in ten directions.
Output; 12 bit 1 10V simulation; 4 encoders/gratings can be connected.
Feed, with bottom plate.
ACC-34AE: 1/0 expansion board, which mainly has eight channels of 1/0.
Convert SV signal on the main card into 24V input/output signal.
Master card 1/0.
Motor drive equipment is servo motor and ACC- 1+
The intermediate equipment connected by ACC-2 wiring board controls the PMAC motherboard.
The control command is converted into an electrical signal to drive the servo motor to rotate. Main parameter
The figures are: torque, 1.27 Nm; Mass, 0. 173kg. M, (same as 30
Inertia within the times); 3000 rpm, 13 bit incremental encoder.
After the board selection is completed, all parts of the control cabinet are connected.
In this process, six protection switches and four electromagnetic relays were installed to
Ensure the separation of strong and weak current, and ensure the safety of all parts of the circuit. Host selectivity
Ordinary PC, convenient for development and expansion; Use ordinary USB data
Using RS232 data line or PMAC special data line to realize ordinary PC
Communication with the control system.
2 error compensation control
Error compensation includes tool compensation, clearance compensation, screw compensation and.
PID compensation. Among them, cutter compensation, clearance compensation and screw compensation are added.
Influence of cutting tools and ball screws used in machining process on accuracy.
Ring [,:.
2. 1PID control principle
The PMAC controller provides a PID position loop servo filter.
Device, by setting the appropriate 1 variable to adjust each motor.
Curved surface is the main parameter involved in PID regulation and its function;
Ix3o, P parameters and proportional gain provide the rigidity of the system;
Ix3 1, d parameter, differential gain, providing the resistance needed for stability.
Ni;
Ix33, I parameter, integral gain, eliminating steady-state error.
The actual algorithm of PID:
The following errors obtained in the servo period n
FE(n)= CP(n)- a corpse (n);
Actual speed in servo period n
AV(n)= one corpse (n) 18 corpses (n-1);
Command speed in servo period n
CV(n)- (Shanghai (n)-CP (n-1);
Command acceleration in servo period n
Wind (n)-CV(n)-[y (n- 1).
Where: CP(n) is the instruction position in n cycles; A corpse (n) is n weeks.
Actual position during the period; CV(n) is the command speed in n cycles.
2.2 system response analysis before and after system PID parameter adjustment
Perform an impulse response. Wait for the host to download data and continue processing data.
Collect and draw the collected data into the ratio of position curve to command curve.
Contrast (Figure 3). The analysis mode is caused by friction, constant force or system limitation.
The position deviation is analyzed. Figure 4 shows the impulse response curve after parameter adjustment.
Compared with Figure 3, it can be seen that the system is pulse-aligned after improving the rigidity parameters.
The following error of impulse response is reduced and the response time of the system is shortened.
The grinding accuracy of the grinding wheel of the system is improved, so by properly improving
Ix30 proportional gain improves the rigidity and tracking accuracy of the system.
3 control software development
3. 1VC 10+ Develop professional control software.
User application software includes three parts: the man-machine interface of PC.
Applications, communication drivers for communication between upper and lower computers, and
PLC program for monitoring various input and output of PMAC.
The communication program uses Pcomm32 provided by DeltaTau Company.
And pmae.dll']; PLC programs can be found in.
PEWIN32Pro, and then download to PMAC card; man-machine
The interface application adopts VisualC++ of Microsoft.
6.0 language, based on Pmac.dll's dynamic link library.
Application module. Pmac.dll is a group with more than 200 functions.
Dynamic link library, including the communication between PC and PMAC.
All the ways. Use Visua 1C++ to call these functions.
Complete the data exchange between PC and PMAC, and realize machine-to-machine communication.
Control of the bed (Figure 5).
The software is mainly divided into the following parts: main interface for use.
Users can easily and quickly understand the convenience of various functions and operations, including
Most functions; Initialize the interface, including motor selection and sitting.
Selection of reference system and initialization of various parameters; Feed speed interface, through
Over-setting can change the feeding speed; Manual operation interface, you can use
Mouse inching operation, you can also enter the position where the phase is to be adjusted.
It should be operation, combined with feed rate application; Program editing and running cycle
Surface, where you can open the compiled processing program (TXT
File, NC file and PMAC file), write or modify the processing project.
Order, run and stop the processing program; Tool calibration interface, you can adjust the tool.
Make up the required value.
3.2 Control panel function realization and PLC programming
Specific buttons are set on the control panel to achieve control.
A more direct and faster control system, such as an optimal refining machine.
Control panel of CNC turning center based on FANUC system
Set program editing area, knob area, manual button area, etc. Yes
Realize X/Y axis selection, fast/slow movement and program simulation.
With the support of PMAC's unique PLC program, the grinding wheel is reformed.
Setting shortcut buttons on the machine control cabinet can make the operation of the machine more convenient.
The control panel has the following functions: 1) zeroing, which is a resetting machine for each axis.
Used when the mechanical origin; 2)X/Y axis selection. Turn this knob to start it.
The axis to be selected so that it can be zeroed and moved; 3) Axial alignment
/negative motion, under the action of simultaneous motion with axis selection, realized
Control of X/Y axis motion.
In PMAC system, PLC program and functions on control panel
There is a one-to-one correspondence. PLC program can be written in PEWIN32Pro.
Download to PMAC card to realize the function of control panel. PLC program
To monitor analog and digital inputs, set outputs, send information, monitor
According to the motion parameters, execute the command like the host, change the gain and turn on.
Starting and stopping exercise is particularly useful.
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Bi Tao, Li Guang, Li Na, et al. Research and application of form grinding technology.
Journal of Anhui Electronic Information Vocational and Technical College, 2007( 1): 16.
Liu, Wang Bin. Open high-precision motion control based on PMAC.
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Bai, Peng Yuhai, Numerical control system software based on PMAC.
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PMAC User Manual of Beijing Yuanmaoxing Control Equipment Co., Ltd.
[z]: 3- 184。
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