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« on: February 17, 2016, 01:22:48 AM »
Machine corrds are NOT always in Q1 and you are NOT simply working in Q1 IF you are probing at X0Y0 1 leg of X COuld be in Q1 and the second leg could be in Q2 OR several different combinations of Quadrants.
Either way YOU are working in Work corrd not machine corrds and all teh math is based on Work Coords(G90) or inc values (G91)
A classic example of teh %problem . Remember you are dealing with an abs positional value (#2000). IF X1 = 1.000 then X1* .90 = .9 so your slow zone would be .10" and that seems resonable NOW if you were probing at X30 then using the same formula X1 *.90 = 27 so that gives you a slow zone of 3" . The entire idea is to make everything consisitant . With using % it will depend on WHERE you are on teh table as to teh value you get.
You want your back off values to always be the same and teh Slow Zone distance to always be the same distance so that ANY variable induced by the probe will cancel itself out .
Gerry have you tried teh math based on teh exact same move (Center of X ) Do it in Q1 where both vlaues are + then do it in Q2 where both values are - and teh offset distance from Zero inverts but your probing routine order of moves stays teh same ( Probe left then right)
You will run into teh same problem solving angles for G68 rotation as the formula changes from Quad to Quad. You have to TEST teh values to find out what Quad you are actual in so you can use the correct formula.
IN this case (Center of X)
IF X1 >0 AND X2 >0 then you are in Q1
If X1 <0 AND X2 <0 then you are in Q2
IF X1 <0 AND X2 >0 then you are in both Q1 and Q2
In the case of Center of X in Q1
G91 G31 X-10 ( Probe left)
Assume X1 =3
G91 G31 X20 ( probe right)
and X2 =6
X2-X1 = X3 ( Distance between X1 and X2)
X3 = 3"
X3/2 = X4 ( 1/2 distance = distance from either of teh refpoints to teh center point)
x4 = 1.5"
x1 + x4 = x5 ( Move from an ABS Ref point(X1) over to the center point)
X5 = X4.5
G90
G0 X4.5 ( moves you to the center of X)
This will work no matter where you are in Q1 as long as you do not move outside of Q1.
To find a slow down zone
X2-X1 = X3
X3/2 = X4
X4-.050 = X5
X5 =1.450
or
(((X2-X1)- .100) /2) = 1.45
Just a thought, (;-) TP
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