Kinematic and Dynamic Analysis of Monoshock Rear Suspension

Motorcycle segment is growing very fast in India. The average riding speeds are much less owing to the road conditions and traffic. The roads have a mix of both high undulations as well as smooth and flat surfaces on highways. Achieving a very good level of ride comfort on such rough & smooth terrains combined with an equally good level of handling in the speed range of 20 to 80 Kmph is a highly challenging task. Monoshock rear suspension is one of the options engineers can look at, to enhance the handling behavior of motorcycles without compromising on the ride comfort too much. Our work is aimed at building a generic analytical model of typical mono shock motorcycle rear suspension that will enhance the understanding of system kinematics and extending its application for optimizing the design towards a better performance of the complete motorcycle. Both direct mount and linkage mount monoshock suspensions are studied. Mathematical equations are derived to get various operating parameters of the suspension system. Using this analytical model, parametric study is done to identify the key design parameters for desired suspension characteristics. Further, the dynamic behavior of a typical motorcycle with monoshock rear suspension is verified using ADAMS. The virtual motorcycle is tested through simulation, on different types of road to assess the ride and handling behaviour and the results are discussed in comparison against traditional twin shock rear suspension.