Although renowned for their flexibility, robots can still be limited by their end effectors. For example, equip your favorite SCARA robot with a suction gripper, and it will be hard-pressed to perform a weld. In many cases, an assembler must quickly switch out a robot's end effector to maximize the robot's ROI. But, doing so can be surprisingly difficult, given each effector's need for I/O connectors, and utilities like electric and pneumatic power.
It was with this hurdle in mind that manufacturers began experimenting with automated tool changers back in the 1980s. In the beginning, there were problems. Tool changers could be unreliable and were apt to drop their end effectors if they lost power. However, today, tool changers are a mature technology, with fail-safe mechanisms assuring that welders or grippers will stay where they belong.