Your Search Results

Use this resource - and many more! - in your textbook!

AcademicPub holds over eight million pieces of educational content for you to mix-and-match your way.

Experience the freedom of customizing your course pack with AcademicPub!
Not an educator but still interested in using this content? No problem! Visit our provider's page to contact the publisher and get permission directly.

A microfabricated three-degree-of-freedom parallel mechanism

By: Mehregany, M.; Behi, F.; Gabriel, K.J.;

1990 / IEEE

Description

This item was taken from the IEEE Periodical ' A microfabricated three-degree-of-freedom parallel mechanism ' A microfabricated, three-degree-of-freedom, passive, closed-chain, planar mechanism with the potential for low-torque precision positioning applications is presented. A parallel-link mechanism design is selected rather than a serial-link implementation, since parallel-link mechanisms can operate with stationary actuators and are more rigid than their serial counterparts. Polysilicon surface micromachining is used to fabricate a mechanism which has a total area of 0.13 mm/sup 2/ and a workspace of approximately 0.01 mm/sup 2/. The fabrication process for the mechanism is described, identifying the effect on device performance of constraints imposed by the microfabrication; most notably joint clearances, component nonplanarity, and residual-stress-induced linkage deformations. The requisite formulations for the kinematics and dynamics of the device are presented which, in conjunction with the documented measurements of friction on structures of similar geometry and material, indicate that the dominant torque loads are due to friction.<>