Rigid Body, Flexible Body, and Micro Electromechanical Systems
Planar multibody systems, and revolute and prismatic joints with clearance and friction are initially modeled in this chapter with Rapson slide and Andrew's mechanism as two examples. For modeling spatial multibody systems, the concepts of noninertial reference frame, Euler angles, and coordinate transformations, etc. are introduced. Hydraulically actuated leg of a Stewart platform and spinning top are modeled as examples. Flexible body systems such as beams, beam columns, composite beams, and bimetallic strips are modeled through spatial discretization and lumped parameter approximation. A thorough treatment is given to modeling of piezoelectric actuators and sensors. Thereafter, models for various microelectromechanical systems (MEMS) like micromirrors, micromotors, magnetohydrodynamic micropumps, wet shape memory alloy (SMA) actuator, and energy harvesting systems, etc. are developed. Further, models of rotor bearing systems with rolling element, journal, and magnetic bearings are developed with special emphasis on active magnetic bearing model. The importance of integrated modeling is shown by considering the case of Sommerfeld effect in a rotor dynamic system and its control through shape memory alloy actuators.