Application of AFDX05 in open five-axis five-linkage CNC system

1. Introduction

Currently, the secondary development of various motion control cards is relatively complicated. However, with the application of high-speed and high-precision motion controllers with five-axis linear interpolation, and the development of various dedicated CNC systems, engineers only need to focus on large-scale and complex software development, and do not need to understand the hardware at all.

2. Hardware system of G code five-axis linkage motion controller

2.1 AFDX05 motion control chip

The AFDX05 motion control chip developed by Yunshan CNC supports any 2~5-axis linear interpolation, any 2-axis circular interpolation, and up to 6 levels of motion command buffers, which are particularly suitable for high-speed multi-line segment or circular continuous interpolation motion control. In addition, it also has reverse gap compensation, speed control, acceleration and deceleration control, position control, general input and output ports, 8/16-bit data bus, interruption, hardware limit, software limit, emergency stop, pause, encoder signal input and other functions, with a drive pulse frequency of up to 8MPPS and an interpolation accuracy of ±5LSB. It is used to control servo motors and stepper motors input in pulse sequence mode.

The "Chinese chip" AFDX05 is more in line with the usage habits of Chinese people.

CPU is S3C44B0X. 32M Flash. Pulse direction differential output driver. 60 optocoupler isolated inputs and 42 open collector optocoupler isolated outputs or 36 optocoupler isolated inputs and 20 open collector optocoupler isolated outputs. 5 stepper/servo motor pulse optocoupler isolated outputs, maximum frequency 4MHz. 32-bit logical position and actual position counter. RS232 communication. The hardware part has been modularized and can be developed without any hardware knowledge.

3. Software system of G code five-axis linkage motion controller

3.1 Supported G-codes

G code Group Function

*G00 1 Positioning (rapid movement)

*G01 1 Linear interpolation (feed speed)

G02 1 Clockwise circular interpolation

G03 1 Counterclockwise circular interpolation

G04 0 Pause, precise stop

*G17 2 Select X plane

G18 2 Select Z plane

G19 2 Select Y plane

G27 0 Return and check reference point

G28 0 Return to reference point

G29 0 Return from reference point

G30 0 Return to the second reference point

*G40 7 Cancel tool radius compensation

G41 7 Left tool radius compensation

G42 7 Right tool radius compensation

G43 8 Tool length compensation +

G44 8 Tool length compensation -

*G49 8 Cancel tool length compensation

G52 0 Set local coordinate system

G53 0 Select machine coordinate system

*G54 14 Select workpiece coordinate system No. 1

G55 14 Select workpiece coordinate system No. 2

G56 14 Select workpiece coordinate system No. 3

G57 14 Select workpiece coordinate system No. 4

G58 14 Select workpiece coordinate system No. 5

G59 14 Select workpiece coordinate system No. 6

*G60 0 Single direction positioning

G64 15 cutting mode

G65 0 Macro program call

G66 12 Modal macro program call

*G67 12 Modal macro program call cancel

*G90 3 Absolute value command mode

*G91 3 Incremental value command mode

G92 0 Workpiece zero point setting

*G98 10 Fixed cycle returns to the initial point

G99 10 Fixed cycle returns to point R

3.2 Supported M codes

M code function

M00 Program stop

M01 Conditional program stop

M02 Program End

M03 Spindle forward

M04 Spindle reverse

M05 Spindle stop

M06 Tool Exchange

M08 Cooling on

M09 Cooling off

M18 Spindle orientation release

M19 Spindle Orientation

M30 ends the program and returns to the program header

M50 spare output 1 open

M51 Standby output 1 off

M52 spare output 2 open

M53 spare output 2 open

M54 spare output 3 open

M55 spare output 3 open

M56 spare output 4 open

M57 spare output 4 open

… …

M98 calls a subroutine

M99 Return after subroutine ends/repeat execution

3.3 Macro Programming

Variable number Variable type Function

#0 "NULL" This variable is always empty and cannot be assigned a value.

#1~#33 Local variables Local variables can only be used in macros to keep the results of operations. When the power is turned off, local variables are initialized to "empty". When the macro is called, the independent variable is assigned to the local variable.

#100~#149

#500~#531 Public variables Public variables can be shared between different macro programs. Variables when the power is turned off.

#100~#149 are initialized to "empty", while variables #500~#531 hold data. Public variables #150~#199 and #532~#999 are optional, but when these variables are used, the length of the paper tape is reduced by 8.5 meters.

#1000~ System variables System variables are used to read and write various NC data items, such as current position and tool compensation value.

#2000~#2059 IO input 60 channels of optocoupler isolation input signals.

4. Three-axis milling machine CNC system development example

4.1 Parameter Initialization

The following parameters are for each of the five axes.

Parameter Name Parameter Setting Parameter Unit

Pulse equivalent P01=XXX.XXXXXX mm

G00 command speed P02=XXXX mm/min

G01 command speed P03=XXXX mm/min

G02 command speed P04=XXXX mm/min

G03 command speed P05=XXXX mm/min

Starting speed P06=XXXX mm/min

Acceleration time P07=XXXX milliseconds

Positive soft limit P08=XXXX mm

Negative soft limit P09=XXXX mm

Backlash compensation P10=XXXX mm

Zero return speed P11=XXXX mm/min

Manual speed P12=XXXX mm/min

Maximum feed speed P13=XXXX mm/min

Total number of tools in the system P14=XX

M code waiting time P15=XXXX milliseconds

Return to reference point coordinates P16=XXX.XXXXXX mm

Spindle encoder line number P17=XXXX (/R)

Zero return direction P18=X

Tool change reference position P19=XXX.XXXXXX mm

Tool change safety height P20=XXX.XXXXXX mm

Tool change interval P21=XXX.XXXXXX mm

Tool change speed P22=XXX.XXXXXX mm/min

Maximum stroke P23=XXX.XXXXXX mm

Set workpiece coordinate system P25 = XXX.XXXXXX mm

4.2 Send G code to control the machine tool operation. For example:

G54

M03 X8

G0 G90 G17

G28

G00X-2.046Y59.111Z10.000

Z4.000

G01Z-1.000F300

G17

G02X1.245Y54.864I-54.422J-45.566K0.000F800

X2.203Y53.318I-15.407J-10.613K0.000

G00Z10.000

G91 G28 M09

V. Summary

Based on the open five-axis five-link CNC system platform, application development engineers can focus on developing specific industry-specific CNC systems without having to understand the hardware, thus reducing the development cost of CNC systems and promoting the popularization and application of CNC machine tools.