Comparison of path following controllers for autonomous vehicles

Abstract

The driver assistance systems becomes more common in today's vehicles, and in the future highly automated vehicles and large number of autonomous vehicles will appear in roads. In the beginning these systems only support the human driver, but later they will able to control the vehicle driving. Hence vehicles have to plan the path, and follow it accurately and safely. Furthermore it has to provide convenience for the passengers. To find a better trajectory following controller first it is necessary to test it in simulation environment, then to test it in real environment in a vehicle. The subject of this article is an implementation of a lateral dynamic bicycle model, and an implementation of different controllers. Besides it will contain the testing of the controllers. If the controllers work with sufficient precision in the simulation, it will be tested in a real vehicle. The essence of the test is the speed limit, where the simulation and the real test starting to deviate. In the end of the article we compare the performance of the different controllers and evaluate which is the most appropriate. Besides the difference will also be evaluated between the simulated results and the results on the real vehicle. This comparison reveal which is the speed limit, as long as the values calculated on the lateral dynamic bicycle model approximate the actual results in a simulation environment with sufficient precision.