# How to calculate the coordinate with Fanuc R-J3iB

• I work with a Robot Fanuc 100iD with a R--J3iB CONTROLLER.

This a Welding Robot. The robot use a rotating table MotoFil mount

on the X axe. So, when the table moves, the Y and Z change.

I welded a part when the table was at 45 degrees.

I wrote the coordinates of joints J4, J5 and J6.

The coordinates of this piece was:

GP1:

UF : 5, UT : 1, CONFIG : 'N U T, 0, 0, 0',

X = 297.592 mm, Y = 255.413 mm, Z = -211.301 mm,

W = -31.373 deg, P = 54.176 deg, R = 154.253 deg,

E1= 148.760 mm

GP2:

UF : 5, UT : 1,

J1= 225.001 deg

};

I tried to weld a piece located in the opposite direction.

I looked at the new coordinate and it was:

GP1:

UF : 5, UT : 1, CONFIG : 'N U T, 0, 0, 0',

X = 384.336 mm, Y = 255.413 mm, Z = -211.301 mm,

W = -31.373 deg, P = 54.176 deg, R = 36.000 deg,

E1= 235.504 mm

GP2:

UF : 5, UT : 1,

J1= 225.000 deg

};

I thought I saw as coordinated:

W = -31.373 deg, P = 54.176 deg, R = 25.474 deg

Why there is a difference on R (J6) and if I try R=24.474, the robot points to different place ?