Experimental and theoretical analysis of a smart transmission mechanism system

This paper focuses on a smart transmission mechanism system, designed and fabricated based on compliant mechanisms. The system was assembled using a piezo-stack actuator in conjunction with a rhombus-type amplifier, a novel transmission mechanism synthesized with flexure hinges, and an active rotatable flap. This assembly is able to be utilized in smart structures to dynamically transfer linear motion generated from some actuators to rotational motion of active rotatable flaps from a long distance at a wide range of frequencies (1Hz similar to 64 Hz). The Lagrangian approach was utilized for dynamic analysis of the system to evaluate the fundamental natural frequency of the smart transmission mechanism system, and the result is 385 Hz; the error is 9% compared with a finite element analysis using ANSYS. Then force and displacement transmissibility of the system was also theoretically calculated based on a newly established theoretical model, and the detailed finite element analysis was also performed to study these properties. A prototype of the smart transmission mechanism system and a special test platform were manufactured to test the force and displacement transmissibility then the transmissibility was experimentally tested. The theoretical and numerical results found a good correlation with the experimental results, and the errors between experimental and theoretical (or numerical) results are within 13% (or 11%). The newly designed transmission mechanism system and the corresponding theoretical, numerical and experimental studies are able to direct the optimal design of some smart systems which consist of compliant mechanisms and transmission mechanisms. They can also offer fundamental information on the active vibration control using some piezo-stack actuators to actuate active flaps.