Modified chain algorithm to study planar compliant mechanisms

Interactive simulations in Virtual Reality, such as haptic interaction, are more and more used to test or optimize nonlinear mechanical systems subjected to large deformations. FE algorithms are often not suitable for such purposes due to the high computational burden and the long simulation times. This paper provides a modified version of the classic chain algorithm, referred to as modified chain algorithm (MCA), to overcome some convergency issues and reduce the simulation time. The proposed algorithm is able to reduce the number of iterations estimating two kind of average moment laws. The MCA is then integrated into a design optimization procedure for the synthesis of a double slider-crank compliant mechanism to be used as opening system for an adjustable bicycle saddle. Finally, a X-Y layered ABS prototype is manufactured by rapid prototyping technique and 3-D printer. Experimental setup to test the deflection of the prototype revealed in good accordance with results coming from the MCA.