Suspension Strain Correlation Using Flex Bodies in MBD

Automotive Suspension is one of the critical system in load transfer from road to Chassis or BIW. Using flex bodies in Multi body simulations helps to extract dynamic strain variation. This paper highlights how the MBD and FE integration helped for accurate strain prediction on suspension components. Overall method was validated through testing. Good strain correlation was observed in dynamic strains of constant amplitude in different loading conditions. Combination of different direction loading was also tested and correlated. Method developed can be used in the initial phase of the vehicle development program for suspension strength evaluation.

Suspension is one of the important system in vehicle which is subjected to very high loading in all the directions. To predict the dynamic stresses coming on the suspension system due to transient loads, faster and accurate method is required. To accelerate the suspension design process it become necessary to get good accuracy in the results. This also ensures first time right design to reduce the time for virtual validation. To achieve these objectives suspension strain correlation exercise was undertaken. Front suspension is modeled in Hyperworks Motionview software. Flex bodies are used for modeling the suspension components. Test setup to measure the strains on suspension components was developed in lab. Initially the validations of the MBD model and test setup was done for static loading. After validating the model for static loading it was used for dynamic loading. Loading was done in all three directions and strain correlation was done with test results. Analysis was also done for long wave pitching test track with dynamic loading and good correlation was observed.