Technical Manual, Sec. 4, Ch. 4: Indsutrial Robots and ...

Axis: The line about which a rotating body such as tool turns. Barrier: A physical means of separating persons from the restricted envelope (space). Control Device Any piece of control hardware providing a means for human intervention in the control of a robot or robot system, such as an emergency-stop button, a start button, or a selector switch. ................
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