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xp p( u, v) = yp

zp

(u=0,v=0) (u=1,v=0)

• A simple algorithm to cut the surface is shown below.

dirn_flag = 1; a direction flag

n=10 ; number of passes to cut the surface step=1.0/n ; step sizes for u and v directions

start=step/2 ; the start offset in the u and v directions [xp,yp,zp] = p(start,start) ; calculate the start position

print(“G00 X”,xp,” Y”,yp,” Z”,zp+0.2) ; move the tool to above the start position for i=0 to (n-1) ; will increment in the u direction

for j=0 to (n-1) ; will increment in the v direction ; calculate next point

if dirn_flag=-1 then [xp,yp,zp]=p(start+i*step,start+j*step)

if dirn_flag=1 then [xp,yp,zp]=p(start+i*step,start+(n-j)*step) print(“G01 X”,xp,” Y”,yp,” Z”,zp) ; instruction to cut to next point

next j ; make next step in v direction until done

dirn_flag = -dirn_flag ; reverse direction to cut in opposite direction next i ; move to next cut line in the u direction

print(“G00 Z”,zp+0.2) ; move the tool to above the end position

15.6 NC CONTROLLERS

• NC control programs are essentially quite simple. The source code for a basic controller is

given below.

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********** Add in C-code for AMP project

15.7 PRACTICE PROBLEMS

1. Examine the part below. It is set up so that the origin is at the bottom left. The cutting tool has a diameter of 1/2”, and the material is 1/8” thick.

2.500”

2.000”

5.500” 2.000”

a) Write the equations needed to find the tangency point on the top left of the piece.

LAT = x2T + y2T = 22 + ( 5.52 + 4.52) 2

b) Develop an NC program to mill the part. The program should be complete and include all instructions required. If necessary, assume a location for the tangency point.

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Integration of CNC equipment.

Overview:

Students will develop programs to load and unload the NC machines with robots, and then produce parts.

Pre-Lab:

1.Use your NC programming software to generate an NC program to cut the top 1/2” of a 3” radius ball on the mill. Test the program on-line.

2.Use the NC generation software to cut a 1/4” deep, 2”long oval into the surface of a 1” brass bar. Test the program on-line.

3.Simulate both programs before arriving at the laboratory.

4.Develop a robot program to load/unload the NC mill with the RV-M1. Test the program on-line

5.Develop a program for the RT-3000 to load/unload the lathe. Test the program on-line.

In-Lab:

1.In the lab test the programs on the different devices in groups of 3

2.One group of (6?) should connect the RV-M1 to the Mill, and the other group should connect the RT-3000 to the lathe.

3.The groups that did the connection should split into smaller groups and modify the programs on the robots and NC machines.

Submit:

1.Your individual NC and robot programs.

2.The final group NC and robot programs.