Flexure joints are frequently used in precision mechanisms, from motion stages to micro-robots. Due to their monolithic construction and superior wear and loss properties, flexure joints can be used to reduce the mechanism size and increase the positioning accuracy. The compliance of flexure joints, however, can affect the static and dynamic characteristics of the overall mechanism. The objective of this thesis is to develop analysis and design tools for general platform type parallel mechanisms that contain flexure joints.; For the mechanism design, we consider performance measures such as different attributes of the task space stiffness and manipulability matrices (regarded as ellipsoids), and constraints such as joint stress, mechanism size, and workspace volume. Based on these performance measures and constraints, we pose the mechanism design as a multi-objective optimization. A Pareto frontier is first computed, and secondary design criteria, such as sensitivity and dynamic characteristics, are then applied to select the final design. To reduce the computation load and facilitate design iteration, the pseudo-rigid-body model is used as an approximate description of the behavior of flexure mechanisms and lumped spring approximation, the Paros-Weisbord model, is used to characterize the flexure joints. Finite element analysis is performed to validate the performance of the final design.; Different types of planar mechanism are included to illustrate the analysis and design techniques. As examples for compliant parallel mechanisms, a 1-DOF meso scale precision stage, a 1-DOF micro scale precision stage, a 1-DOF micro gripper, and a 3-DOF micro scale parallel robot are examined. Tools presented in this thesis can also be applied to a broader class of compliant mechanisms, including robots with inherent joint flexibility as well as compliant robots for contact tasks.
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