Cobot Architecture
Michael A. Peshkin, J. Edward Colgate, Witaya Wannasuphoprasit,
Carl A. Moore, R. Brent Gillespie, and Prasad Akella
IEEE Transactions on Robotics and Automation, Vol. 17, No. 4, pp. 377-390,
August 2001.
Abstract—We describe a new robot architecture: the collaborative robot, or
cobot. Cobots are intended for direct physical interaction with a human
operator. The cobot can create smooth, strong virtual surfaces and other haptic
effects within a shared human/cobot workspace. The kinematic properties of
cobots differ markedly from those of robots. Most significantly, cobots have
only one mechanical degree of freedom, regardless of their taskspace
dimensionality. The instantaneous direction of motion associated with this
single degree of freedom is actively servo-controlled, or steered, within the
higher dimensional taskspace. This paper explains the kinematics of cobots and
the continuously variable transmissions (CVTs) that are essential to them.
Powered cobots are introduced, made possible by a parallel interconnection of
the CVTs. We discuss the relation of cobots to conventionally actuated robots
and to nonholonomic robots. Several cobots in design, prototype, or industrial
testbed settings illustrate the concepts discussed.