Machine Case Study: Mechanical Performance of a Quick- Change Industrial Robot Factory Interface

This chapter applies the previously discussed kinematic coupling design, repeatability, and interchangeability theory to development of a new factory interface for base mounting of industrial robots, used primarily in automotive body assembly welding, sealing, and material handling. Because of the extreme forces and torques at the manipulator base during robot operation and the critical nature of interface stability, design choices are restricted to large-radius canoe ball couplings, and quasi-kinematic alternatives with larger contact areas. When the relative positions of the contact points are pre-recorded and the interface transformation is calculated, use of a kinematic base interface is a step toward installation of a replacement manipulator without need for online recalibration. The calibrated kinematic couplings reduce the resultant error at the tool center point (TCP) by over 85% relative to the best current design. This improvement is demonstrated through tests of a prototype interface for the ABB IRB6400R 150kg payload industrial robot.