Verification of Vehicle Dynamics Control Functions
Examensarbete för masterexamen
Automotive engineering (MPAUT), MSc
This thesis presents the development of a Model-in-the-Loop test bench which's function is to ensure system safety by verifying vehicle dynamics control functions; making sure that they do not cause any dangerous situations for a certain vehicle (e.g. SAAB 9-3) including all vehicle variants (e.g. station wagon/sedan), load cases, manoeuvres and road conditions, creating an infinitely large test matrix. This forces the test bench to be able to generate a statistically motivated finite sample from that test matrix using design of experiments, specifically Latin hypercube sampling. The test bench then simulates and analyses the vehicle behaviour in the different manoeuvres and road conditions and presents the results in a way which gives the user a good overview of the vehicle behaviour induced by the control function. An empirical study of how many simulations are needed for the results to converge is also presented. A use case, considering the development of a regenerative braking control function demonstrates the effectiveness and performance of the test bench. Conclusions drawn include that the test bench is able to give good indicative results during the development process of a control function but also that the vehicle model needs further evaluation and verification in order for the results to be interpretable as more absolute and real. This to make them usable in the verification of a specific control function with a higher level of maturity. The vehicle model should, however, be kept fast enough to make it reasonable to run thousands of simulations as part of a development process.
Teknisk mekanik , Farkostteknik , Transport , Applied Mechanics , Vehicle Engineering , Transport