Design and Fabrication of a Four Degree-of-Freedom Force Feedback Planar Manual Controller

摘要

State of the art teleoperator controllers for manipulators are represented by bilateral master-slave devices. These position forward, force-feedback devices rely on a geometric similarity between the manipulator and the controller (slave and master) and simplistic control schemes to operate. During operation, the slave replicates the master's configurations. The operator must be aware of the manipulator configurations, workspace obstacles, and the details of the ongoing task. This burden increases with the number of degrees-of-freedom. Joystick technology for teleoperator manipulators attempts to utilize machine intelligence to augment the operator and thereby reduce his efforts during manipulator control. The operator can focus his attentions to the task while the computer deals with the manipulator configurations and workspace obstacles. When the task is trivial or repetitive, the computer can take over and relieve the operator via the use of preprogrammed routines. Joysticks are geometrically dissimilar to the manipulators being controlled. This lack of geometric correspondence allows for further capabilities such as scale change for motions, motion filtering to eliminate. Force-feedback is a basic necessity for teleoperators. Through this control system the operator is tactilely aware of the loadings occurring at the manipulator. During activities in which the manipulator is lifting or twisting an object, the operator will feel a scaled force or torque. Inertialess control and obstacle encounters are other capabilities possible with force-feedback control schemes. (ERA citation 09:031378)