Dynamics of a Bistable Mechanism with Parallel Beams and Permanent Magnets
Besides the three main categories of bistable mechanisms such as latch-lock mechanisms, hinged multisegment mechanisms, and residual-compressive-stress buckled beams, a novel unsymmetrical bistable mechanism with a combined structure of permanent magnets and mechanical beams is proposed, and the bistability of such combined structure is analyzed based on the magnetic-charge model and material mechanics theory. The nonlinear combined force during snap-through procedure is calculated accurately, which is in accordance with that obtained by the experiments. The bistable characteristics such as the threshold snapping force, the traveling range, stable positions, and the elastic reaction force at the stable position can be adjusted freely by changing the magnet structure parameters and the relative distance among the three magnets. Finally, the dynamic response is analyzed theoretically and experimentally, which shows that the bistable structure has a good frequency distinguishing capacity for mechanical shock pulses.
J. Zhao et al., "Dynamics of a Bistable Mechanism with Parallel Beams and Permanent Magnets", Advanced Materials Research, Vols. 308-310, pp. 508-512, 2011