Force control for a Grinding application

RAPID Programming
1

HI,

Am working on a project with force Control to do a grinding operation ( IRB 4600, IRC5 controller, Robotware_6.09.0154)

when the grinder turned on my force value is fluctuating, it goes like -200 to 200N(in mid air)

how do i stabilize this?

Did i miss anything ? please help me correct this.

var num nforce;

var num nAngleY;

nforce=10

TempLoad:=FCLoadID(\LoadidErr:=nFcloadErr);

FCCalib TempLoad;

!Grinder On

FCPress1LStart reltool(Apoint,0,0,0\Ry:=nAngleY), v20\Fz:=nForce, 80\ForceFrameRef:=FC_REFFRAME_WOBJ \ForceChange:=50 \DampingTune:=100 \TimeOut:=5 \UseSpdFFW,\PosSupvDist:=10, z1, t4inGrinder\WObj:=WbjGrind;

FCPressL reltool(ABpoint,0,0,0\Ry:=nAngleY),v20,nForce,z1,t4inGrinder\WObj:=WbjGrind;

FCPressL reltool(Bpoint,0,0,0\Ry:=nAngleY),v20,nForce,z1,t4inGrinder\WObj:=WbjGrind;

FCPressEnd rGrindingEnd_1,v50\DeactOnly,t4inGrinder\WObj:=WbjGrind;

!Grinder Off

And to check the force real time am using the instruction Fcgetforce(\contact force)

Thank you

2

I think you need to add identify the load and calibrate, from the Force Control manual the basic approach to creating a program is:

1 Identify the load.
2 Move to a point close to contact but not in contact.
3 Calibrate.
4 Setup force control directions and start movement.
5 Move linear or circular with contact.
6 Leave surface.

Example below is with force Z with a movement in x-direction
PROC press1()
PERS loaddata TestLoad:=[0.001,[0,0,0.001],[1,0,0,0],0,0,0];

! Identify the load using the sensor
TestLoad:=FCLoadID();

! Move close to contact
MoveJ offs(B,0,0,2) , v100, fine, tool0; !! start 2mm above contactpoint

! Calibrate the force sensor
FCCalib TestLoad;

! Approach surface and start move to robtarget C at 50% of
! 60 N i.e 30 N
FCPress1LStart C, v100, \Fz:=60, 50, z30, myTool;

! Move Linear from C to D1 with a Force of 50 N in the z-direction
FCPressL D1,v100,50,z30,myTool;

! Move Linear from D1 to D2 with a Force of 70 N in the
! z-direction
FCPressL D2,v100,70,z30,myTool;

! Leave surface and move to robtarget E, Force control
! is disabled after this instruction
FCPressEnd E, v100,myTool;
ENDPROC

3

I understand this part, my problem is when i turned on the grinder in force value is fluctuating drastically because of that when i tried applying constant force robot is going in random direction.

4

You should have the grinder running before doing the calibration.

5

yes it worked , Thankyou