COMMENT ⊗   VALID 00010 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002		WESTERN ELECTRIC -MODEL STANFORD ARM CALIBRATION
C00004 00003	JOINT #1:
C00005 00004	JOINT #2: 
C00006 00005	JOINT #3:  
C00008 00006	JOINT #4: 
C00009 00007	JOINT #5: 
C00010 00008	JOINT #6:  
C00012 00009	HAND:
C00013 00010	JOINT STOP LIMITS:  03 DEC 1976
C00015 ENDMK
C⊗;
	WESTERN ELECTRIC -MODEL STANFORD ARM CALIBRATION


KINEMATIC ARM CONSTANTS:  1 DEC 1976

	S1 = 17.805 inches
	S2 =  6.535 inches
	S6 =  7.985 inches

	Shoulder assumed to be located at [0,0,S1]



TRANSFER FUNCTIONS FOR THE "ARM" PROGRAM

	Joint Angle ← (ADC reading * SCALE) + OFFSET

	DAC value   ← (Joint Angle - BOFFST)*BSCALE


The constants for these equations can be computed from the calibration
data as follows:

	SCALE  ← (change in degrees/change in ADC reading)

	OFFSET ← degrees - ( ADC reading ) * SCALE

	BSCALE ← 1.0/( DSCALE*SCALE )

	BOFFST ← OFFSET + DOFFSET*SCALE

   where

	DSCALE ← (change in final pot pos./change in DAC output)

	DOFFST ← pot reading - ( DAC value*DSCALE )



NOTE:  For the pot readings, an asterisk ( * ) is used to indicate 
       questionable readings.
JOINT #1:

Pot Calibration: 1 DEC 1976

	Set Point	 A/D		Partial Differences

	   0.0		 2695
	-90.0		 1632  		

	Difference:	 90/1063
	SCALE:		 .08466
	OFFSET:		-228.158 deg

Dac to Pot Calibration: 1 DEC 1976

	Dac Output	Pot Reading	Partial Differences

	-1000.		  1048
	   0.		  2049		1001
	 1000.		  3049		1000

	Difference:	2001/2000
	DSCALE:		1.0005
	DOFFST:		-12.5

Joint Angle to DAC conversion constants:

	BSCALE:		11.806
	BOFFST:		-54.690
JOINT #2: 

Pot Calibration: 1 DEC 1976

	Set Point	 A/D		Partial Differences

	 -180 DEG	 3059.	
        - 90.0		 2004.	
	   0.0		  953.	


	Difference:	-180./2106
	SCALE:		-.08547
	OFFSET:		81.453 deg

Dac to Pot Calibration: 1 DEC 1976

	Dac Output	Pot Reading	Partial Differences

	-1000.	         1048.		     
	  0		  2049		1001
	1000.		  3049		1000 

	Difference:	2001/2000
	DSCALE:		 1.0005
	DOFFST:		-13.278

Joint Angle to DAC conversion constants:

	BSCALE:		-11.694
	BOFFST:		-93.675
JOINT #3:  

Pot Calibration: 1 DEC 1976

Distance measured is distance from centerline of shoulder to
centerline of wrist.

	Set Point	 A/D		Partial Differences

	7.5 INCHES	3450
	28.5		1030
	

	Difference:	27.0/3129.
	SCALE:		-.0086289   
	OFFSET:		37.4381    

Dac to Pot Calibration: 1 DEC 1976

	Dac Output	Pot Reading	Partial Differences

	-1000.		 1049.
	    0.		 2049.		1000
	 1000.		 3049.		1000

	Difference:	2000/2000
	DSCALE:		-1.0000 
	DOFFST:		-12.00 

Joint Angle to DAC conversion constants:

	BSCALE:		-115.8896
	BOFFST:		19.7575 
JOINT #4: 

Pot Calibration: 1 DEC 1976

	Set Point	 A/D		Partial Differences

	 -90.0		 1715.	
	-270.0		 3818	
	

	Difference:	-180/2103
	SCALE:		-.0852541    
	OFFSET:		56.7903 deg

Dac to Pot Calibration: 1 DEC 1976

	Dac Output	Pot Reading	Partial Differences

	-1000.		 1048.
	    0.		 2048.		1000
	 1000.	         3050.		1002

	Difference:	2002/2000
	DSCALE:		1.001
	DOFFST:		-11.0

Joint Angle to DAC conversion constants:

	BSCALE:		-11.7185
	BOFFST:		-117.810
JOINT #5: 

Pot Calibration: 1 DEC 1976

	Set Point	 A/D		Partial Differences

	 -90.0		 582.
	   0.0		 2027.		
	  90.0	         3351.		
	

	Difference:	180./2769. 
	SCALE:		.06659267   
	OFFSET:		-131.765deg

Dac to Pot Calibration: 1 DEC 1976

	Dac Output	Pot Reading	Partial Differences

	-1000.		 1048.
	    0.	         2048.		1000.
	 1000.		 3049.		1001.

	Difference:	2001/2000
	DSCALE:		 1.0005
	DOFFST:		-11.0

Joint Angle to DAC conversion constants:

	BSCALE:		15.00909
	BOFFST:		4.616788
JOINT #6:  

Pot Calibration: 1 DEC 1976

	Set Point	 A/D		Partial Differences

	- 90.0		 52.
	   0.0		 1118.	
	  90.0		 2208.	
	 180.0		 3282.		


	Difference:	 270./3230.
	SCALE:		.0856211   
	OFFSET:	 	-93.0176 deg	

Dac to Pot Calibration: 1 DEC 1976

	Dac Output	Pot Reading	Partial Differences

	-1000.		 1046
	    0.		 2047		1001. 
	 1000.		 3049 		1002.

	Difference:	2003/2000
	DSCALE:		1.0015
	DOFFST:		-8.0

Joint Angle to DAC conversion constants:

	BSCALE:		11.66187
	BOFFST:		82.2488
HAND:

Pot Calibration: 1 DEC 1976

	Set Point	 A/D		Partial Differences

	   0.0 inches	 3537
	   3.75		 575


	Difference:	 3.75/-2962
	SCALE:		-.001266
	OFFSET:	 	4.4778

Dac to Pot Calibration: 1 DEC 1976

	Dac Output	Pot Reading	Partial Differences

	-1000.		 1048.
	    0.		 2047.		 999.
	 1000.		 3048.		1001.

	Difference:	2000/2000
	DSCALE:		-1.0000
	DOFFST:		2047

Joint Angle to DAC conversion constants:

	BSCALE:		-789.8894
	BOFFST:		1.88116 
JOINT STOP LIMITS:  03 DEC 1976


      Joint	Electrical	Software	Electrical	Software
		Minimum		Minimum		Maximum		Maximum

	1	-205		-203.0		 92.6		 90.0
	2	-183		-180.0		 3.5		  0.0
	3	   7.56		  7.65		 35.9		 35.6 
	4	  -267		 -265		 38		 36.0
	5	-110.		-109.0		110.		109.0
	6	- 86.		- 84.0		236.		234.0
      hand	-  0.06		   0.0		  3.81		 3.79

     		SAME AS ABOVE BUT IN A/D READINGS

     JOINT 	HARD MIN	ELEC MIN	HARD MAX	ELEC MAX

	1	195		270		3840		3790
	2	839		915		3185		3090
	3	160		195		3500		3470
	4	123		235		3860		3810
	5	300		325		3665		3630
	6	0		100		3925		3850
      hand	517		520		3545		3600


Note:  There are three limits  Software, Electrical, and Mechanical.  Software limits
are set just inside electrical limits.  Electrical Limits are set just inside
mechanical limits.