Robotics and Automation Expert
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Decoupled Cartesian Control of Teleoperated Redundant Robots (page 3)

In decoupled-Cartesian control, the operator drives the first five base axes in simple joint mode. The operator controls the last 6 axes in a traditional Cartesian mode. This is the classic DOE teleoperation. The operator is specifying as many kinematic constraints on the system as there are DOF. In this case, the operator is specifying 6 constraints for each EEF location and there are 6 DOF in each arm. Essentially, the operator is in remote control of a state-of-the-art telemanipulator.

Self-motion control allows the operator to drive each of the robot’s axes in joint mode while maintaining the end-effector at a constant location. This allows the operator to optimize the robot’s configuration after establishing a work point. As with decoupled-Cartesian control, the operator is specifying the same number of kinematic constraints as there are DOF in the system. Though the operator is still in remote control of the manipulator, this mode is a useful extension to the capabilities of classic DOE teleoperation.

Implementing both the decoupled-Cartesian and the self-motion modes of teleoperation requires the solving of an inverse kinematics problem. For the DAWM, the geometry of the Schilling Titan II manipulator determines the inverse problem.

Intelligent Assistance - As the interaction between the operator and the machine begins to increase in sophistication, the level of control progresses from manual control to intelligent assistance. This section describes a kinematic configuration advisor implemented as an intelligent operator-assist interface. Through the assist interface, the operator establishes EEF locations for the robot’s two arms. The computer algorithms underlying the interface then use a simulated annealing optimization algorithm to generate a small set of ranked configuration options that satisfy the constraints. The algorithms rank the options based on multiple performance criteria. The interface then presents these options to the operator via a graphical computer interface.