Allen-Bradley 1756-M02AS User Manual page 79

Configure an Articulated Independent Robot Chapter 4
Link Lengths
Links are the rigid mechanical bodies attached at joints. The SCARA Delta
robot has two link pairs each with the same lengths. The link attached to each
actuated joint ( J1 and J2) is L1. The parallel bar assembly attached to link L1 is
link L2.
Base Offset
There is one base offset (X1b) available for the SCARA Delta robot geometry.
Enter the value equal to the distance from the origin of the robot coordinate
system to one of the actuator joints. The base offset value is always a positive
number.
End-effector Offset
There is one end-effector offset (X1e) available for the SCARA Delta robot
geometry. Enter the value for the distance from the center of the moving plate
to one of the spherical joints of the parallel arms. The end-effector value is
always a positive number.
Figure 32 - SCARA Delta End-effector and Base Offset
Rockwell Automation Publication MOTION-UM002E-EN-P - June 2016 79