Motorcycle jump test dynamics and durability analysis

Structural durability and ride comfort are two of the main aspects that determine the reliability of a motorcycle. Simulations in the CAE environment are extensively used to carry out those analyses. Jump test and drop test are widely adopted methods used to analyse the offroad capability of motorcycles. For jump test motorcycles run at a constant speed and are made to take a jump from a ramp of a specific height, so that the vehicle will land on the rear wheel after the flight. During the drop test, the vehicle is made to fall from a height which is equal to the maximum height achieved by the vehicle during the jump test flight. Correlation studies are conducted between the jump test and drop test so that the physical test set-up could be evaluated. Simulation of the jump test of a motorcycle is carried out for the suspension assessment, ride comfort and chassis durability analysis. Simulation is carried out using Dassault Systèmes Simulia suite software tools, Simpack for MBD. Using Abaqus software the chassis flexible body is generated and coupled with the Simpack model. Stresses developed on the frame are calculated based on the principle of modal superposition. Further fatigue life analysis is conducted using fe-safe. Simulation results are correlated with the experimental results. Chassis vertical acceleration, suspension deflection are taken as the correlation factors. The maximum number of jumps that can be performed without the failure of chassis is obtained. The results indicate that the simulation works effectively in analysing motorcycle dynamics and durability.