Collaborative robots - "cobots" - are intended for direct interaction with
a human worker, handling a shared payload. They are a marked departure from
autonomous industrial robots which must be isolated from people for safety
reasons. Cobots are also distinct from teleoperators, in which a human ope
rator controls a robot and payload remotely. Cobots interact with people by
producing software-defined "virtual surfaces" which constrain and guide th
e motion of the shared payload, but add little or no power. Ergonomic as we
ll as productivity benefits result from combining the strength and computer
-interface of the cobot with the sensing and dexterity of the human worker.
This paper explains cobots as one approach to an emerging class of materia
ls handling equipment called Intelligent Assist Devices (IADs). We describe
two cobots of this class presently in industrial testbed settings. Future
applications of cobots' virtual surfaces are tool guidance in image guided
surgery, and haptic display in which the surfaces of a CAD model can be fel
t.