9308663 Wang This project deals with an efficient modeling, design and control method for high speed flexible machines. Impacts within the clearances of such devices can seriously degrade their performance and generate excessive noise and vibration. In this research program, the dynamic behavior of machines is modeled incorporating design parameters such as link elasticity, link lengths, clearance values, and material properties. Practical methods are developed to reduce and control the effects clearances via optimal use of geometric and material properties; an on-line technique for clearance estimation and diagnostics using machine vibration response; and an innovative application of piezoelectric actuators and sensors bonded to the machine links to actively suppress clearance-induced vibration and impact forces. A coordinate reduction procedure, in conjunction with the methods of finite element and harmonic balance, are used to the methods of finite element and harmonic balance, are used to assist in arriving at optimal designs of flexible mechanisms. ***
