| The objective of this dissertation is to contribute to the understanding of the behavior of high-performance mechanisms and the exploration of methods to modify their design and motion such that these mechanism could be operated at higher speeds with greater precision, minimal vibration and control problem.; In the present study, it is shown that in general, the speed-doubling linkage mechanisms require lower peak input torque and less power to operate, and that the amplitudes of higher harmonics of their required input torque are lower. As a result, such mechanisms can be driven with smaller motors, which generally have higher dynamics response characteristics.; In this thesis, a systematic method is also presented for optimal trajectory synthesis for redundant robot manipulators for the purpose of reducing the high harmonic components of the prime actuated joint motions and required actuating torques. A method is also presented for optimal trajectory synthesis for redundant robot manipulators for the purpose of enabling them to perform smooth object manipulation with smooth prime actuated joint motions by synthesizing prime actuated joint and object motions to achieve trajectories that do not contain high harmonic components.; In this thesis, a systematic method is developed for the evaluation of the transmissibility of displacement from smart (active) actuators integrated in the structure of robot manipulators with serial and parallel kinematics chains to the manipulator joint and end-effector displacements. The developed method provides a tool for the determination of the positioning of the smart actuators to provide maximum effectiveness in eliminating high harmonics of the joint or the end-effector (payload) motion.; To achieve the low harmonic actuated joint or the end-effector motions, one can integrate the smart actuators into the links of robot manipulator or place the smart actuators at the end-effector to obtain a micro and macro robot manipulation. However, for the robot manipulator with closed-loop chain, the high harmonics of joint motions within the manipulator loop cannot be eliminated by micro and macro manipulator system, which could be done by integrating smart actuators into the links of robot manipulators. In the last part of this thesis, the advantage of integration of smart actuators into the links of robot manipulators is presented by its application to a plane two-degree-of-freedom robot manipulator with a closed-loop chain performing point-to-point motion. (Abstract shortened by UMI.)... |
