Automatic Ultrasonic Headway Control for a Scaled Robotic Car

Intelligent Transportation Systems and supporting technologies have been an active area of research for some time. Human drivers exhibit slower response times and errors in judgment that can have serious adverse affects on traffic flow. These types of errors can be reduced or eliminated from the driving experience by introducing computer control systems into the automotive arena.

The purpose of this research was to develop a scale model platform for the rapid prototyping and testing of ITS systems and technologies. Specifically, this body of work was concerned with the development of an automatic headway control system that utilized ultrasonic sensors. This control system was intended to automatically maintain headway distance in an effort to create an adaptive cruise control system for this scale model vehicle. Implementation of such systems could conceivably reduce driver fatigue by removing the burden of maintaining safe following distance from the driver.

System dynamics of car-like robots with nonholonomic constraints were employed in this research to create a controller for an autonomous path following vehicle. The application of a working kinematic model describing car-like robotic systems allowed the development of a simple first order controller, as well as a sliding mode controller.

Following the development and simulation of these two control laws, the system was applied to the FLASH project scale model vehicle to assess the practical use of the system on a mock highway. A satisfactory result is produced after testing was completed, and the application of such systems to scale model platforms is feasible.