Search Results

This paper deals with a DC motor driven Electric Power Assisted Steering system integrating a manual rack and pinion steering system. The DC motor is controlled by an electronic controller and connected to the steering system through a set of gears. The DC motor and the steering were modeled using principles of bond graphs and combined with Controller to form the system model. The state equations describing the system were developed using the bond graphs. The performance of the system was simulated using Matlab/Simulink. The electronic controller develops an output voltage to control the DC motor, considering vehicle speed and Steering Column torque inputs. This paper used a regression-weighted function to describe the operation of the controller. Transient and steady state performance characteristics of the system were evaluated including its damping characteristics.

Vehicle Dynamics play an important role in responsiveness of a vehicle. The performance of a vehicle depends on its ride and handling characteristics [1]. Handling is a measure of the directional response of a vehicle and one of the important characteristics from the vehicle dynamics point of view. The directional response of a vehicle depends on the dynamics of the steering system. A good steering control provides an accurate feedback about how the vehicle reacts to the road. In this paper, the powerful techniques of Bond graphs and state equations [2] are used to design and analyze the dynamics of a manual rack and pinion steering system. The author obtains the transfer function between the Angle of rotation of front tire and the Angle of rotation of steering wheel. The overall steering ratio of the bond graph modeled steering system is compared with the overall ratio of a similar vehicle to validate the model.