Abstract: Piezoelectric materials are used in various applications as active vibration control, fault detection in structures and piezoelectric accelerators, therefore, analysis of such materials seems to be necessary in modern mechanical constructions. In this paper, the dynamic analysis of the beam equipped with piezoelectric patches, used as both sensor and actuator, is presented and the beam deflection due to external inputs (force or voltage) is analyzed via modal analysis method. Then, constructing a model for the flexible beam, by the assumed mode approach, an active vibration control is developed by optimal positioning of piezoelectric patches. Simulation results are also presented to illustrate the effectiveness of the methods proposed for dynamic analysis and active vibration control.
Abstract: Aiming at the present gait instable walking-aid, a low cost walking-aid research platform is designed in this paper. The paper developed a dynamic walking aids mechanical design process which based on the study of body's gait stability and motion parameters, analyzed the structural design of the walking aids in ergonomic principles. Furthermore, based on the ZMP gait stability theory, adopting a composed design/integrated optimization gait planning method to program the gait of normal walkers and wearers. Adjusting the ankle joint to the rear foot and the trajectory of the hip’ abscissa is integrated to modify the actual ZMP trajectory to the ideal ZMP trajectory. The proposed composed design/integrated optimization method greatly simplifies the programming process and provides a good experiment platform for walking aid teaching and scientific research.