Passivity-Based Global Chassis Control
With the introduction of driver-assisting control systems and X-by-wire technology, the automotive industry is now able to redesign the interface between the driver and the vehicle dynamical behaviour.
The control systems help to make the car more consistent, predictable and therefore more safe to operate. Besides that, the car can easily be designed to have a specific ‘driving feel’.
However, increasing the degrees of control freedom often results in a complex conglomeration of control systems within the car. It is desirable that a single integrated control system is developed, possibly having a structural hierarchy.
Other relevant complicating factors are:
* Uncertain road conditions
* Changing loading conditions
* Highly nonlinear tyre behaviour (see picture)
This research aims at applying constructive, physics-based nonlinear control techniques to the problem of Global Chassis Control. It is the objective to shape the vehicle’s dynamical behaviour by applying:
* Four-wheel steering
* Differential braking and traction
* Active suspension control
Closed-loop controller synthesis methods can help to keep the controller as simple as possible and preferably physically interpretable. The closed loop should be robust to changes in e.g. friction and loading conditions.
In this project, Passivity-Based Control is used. The area of Passivity-Based Control (PBC) focuses on shaping the closed-loop’s energy, interconnection and damping structure. The system’s passivity properties play a key role in this type of controller design. One of the key advantages of Passivity-Based Control is the fact that nonlinearities can be treated in a natural way. An interesting open issue is a general methodology to incorporate performance specifications into the controller synthesis.
First results will be validated using the full-car simulation environment of Dymola®.
ir. J.J. Koopman (Johan), prof.dr.ir. M. Verhaegen (Michel), D. Jeltsema
Transportation and infrastructure
Delft University of Technology