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This paper reports the design of an optimal controller to prevent suppressvertical vibration due to undesired out of plane excitations generated by environment or gripper during manipulation for a CMOS-MEMS Nano-Newton capacitive force sensor applied for biomedical applications. Undesired out of plane excitations generated by environment or gripper during manipulation is the most prevalent source of vertical vibration in this type of sensors. To suppress the vibrational movement a PZT 5A is used as actuation mechanism. Discrete element method DEM model and Modal analysis were used to find dominant natural frequencies and mode shape vectors. To eliminate out of plane excitation an optimal linear quadratic regulator is proposed using By State-Space formulation. Simulation results illustrate that by employing optimum LQR control approach the maximum disturbance input is suppressed less than 0.7 sec with acceptable range of control voltage amplitude.

The main scope of this article is to simulate a cracked pipeline embedded with piezoelectric sensors and actuators utilizing bond graph approach. Piezoelectric sensors/actuators are becoming very popular in various applications such as health monitoring, active vibration control or noise reduction, and as a part of the systems called smart structures. The proposed bond graph structure in this study, graphically illustrates the power flow between the electrical and mechanical frameworks included in the system. In addition, the proposed framework makes it possible to utilize a modular structure for separately representing the electrical polarization of the material and its macroscopic electrical and mechanical effects. Simulation results illustrate that at the location of the crack the equivalent impedance is increased and the capacitance is decreased in comparison with the intact region.

The aim of the present research is to simulate dynamic behavior of the human auditoria peripherals during sound transmission using the equivalent six-degrees-of-freedom lumped parameter mathematical model. Transmissibility analysis was employed to get a better insight into the sound transmission from tympanic membrane to malleus, incus, stapes, and cochlea. Furthermore, transmissibility from each member to corresponding adjacent member was carried out to functional analysis of the human ear. Simulation study illustrated that the results are in agreement with the experimental results published in the literature, and the proposed model provides more information in the dynamic analysis of middle ear biomechanics.

Several lower extremity exoskeletal systems have been developed for augmentation purpose. Common actuators, have important drawbacks such as complexity, and poor torque capacities. The main scope of this research is to propose a series elastic actuator for lower extremity exoskeletal system which was designed based on muscle functional analysis. For this purpose, a biomechanical framework consisting of a musculoskeletal model with ten degrees-of-freedom actuated by eighteen Hill-type musculotendon actuators per leg is utilized to perform the muscle functional analysis for common daily human activities. The simulation study illustrated functional differences between flexor and extensor muscles and the results were utilized for efficient design of the series elastic torque actuator employed in lower extremity exoskeletons.