A CAE SYSTEM FOR MICROMACHINES - ITS APPLICATION TO ELECTROSTATIC MICRO-WOBBLE ACTUATOR

This paper describes a new computer-aided engineering (CAE) system for micromachines 10(-6)-10(-3) m in size. An automatic finite-element (F E) mesh-generation technique, which is based on the fuzzy knowledge pr ocessing and computational geometry techniques, is incorporated into t he system, together with a commercial FE analysis code, MARC, and a co mmercial solid modeler, DESIGNBASE. The system allows a geometry model of interest to be automatically converted to different FE models, dep ending on the physical phenomena of the micromachines to be analyzed, i.e., electrostatic analysis, stress analysis, modal analysis, and so on. The FE models are then automatically analyzed using the FE analysi s code. Out of the whole process of analysis, the definition of a geom etry model, the designation of local node patterns and the assignment of material properties and boundary conditions to the geometry model a re the only interactive processes to be done by the user. The interact ive operations can be processed in a few minutes. The other processes, which are time consuming and labour intensive in conventional CAE sys tems, are fully automatically performed in a popular engineering works tation environment. With the aid of multilayer neural networks, the pr esent system also allows us to obtain automatically a design window in which a number of satisfactory design solutions exist in a multi-dime nsional design parameter space, considering coupled multiple phenomena such as static and dynamic deformation, thermal conduction, electrost atics, and so on. This CAE system is successfully applied to evaluate an electrostatic micro wobble actuator. As a typical CAE evaluation, w e identify the quantitative conditions for operating the micro wobble actuator, considering both structural and electrostatic phenomena.