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The Ohio State University Center for Intelligent Transportation Research (CITR) has developed three automated vehicles demonstrating advanced cruise control, automated steering control for lane keeping, and autonomous behavior including automated stopping and lane changes in reaction to other vehicles. Various sensors were used, including a radar reflective stripe system and a vision based system for lane position sensing, a radar system and a scanning laser rangefinding system for the detection of objects ahead of the vehicle, and various supporting sensors including side looking radars and an angular rate gyroscope. These vehicles were demonstrated at the National Automated Highway System Consortium (NAHSC) 1997 Technical Feasibility Demonstration in a scenario involving mixed autonomous and manually driven vehicles. This paper describes the demonstration, the vehicle sensing, control, and computational hardware, and the vehicle control software.

We consider a vehicle-roadway system where the control of vehicle movement is based on the instrumentation located both in the vehicle and the roadway. In addition to the sensors which are used for obtaining the information on the vehicle, a radar based sensor system is used for providing information on the position of the car relative to a vehicle ahead, and with respect to a reflective strip placed on the road. The roadway traffic includes standard vehicles with no automatic control as well as the vehicles with automatic control units. Communication between the vehicles is not considered. For longitudinal control, we consider an Radar Based Cruise Control problem where the main goal is to maintain a desired speed set by the driver. At the same time, the controller will decelerate the vehicle if the distance and/or the relative speed between the controlled vehicle and the vehicles traveling in front are below certain limits.

This paper is concerned with Advanced Transportation Systems, in particular, the design of controllers for Fully-Automated Vehicle Operation. We specifically consider the design and implementation of a lateral controller for a cooperative vehicle system being developed at The Ohio State University. The objective of the lateral controller is to steer the vehicle to follow a retroreflector stripe placed on the roadway pavement using radar sensors. The structure and the parameters of the controller are determined during simulations and analytic studies. The controller models are then downloaded into two high-speed computer systems which are interconnected to simulate the operation of the closed loop system in real time and provide a “hardware-in-the-loop” environment. Finally, the computer containing the controller dynamics is installed in the vehicle and field experiments are conducted.

This study is concerned with the development of a radar reflective patch to be used with a look-ahead radar in a convoying application for ground vehicles. The system considers a vehicle following configuration where the leader vehicle has a radar patch attached to its rear and the follower vehicle has a radar transmitter/receiver which obtains headway and orientation information by tracking the radar patch. The headway and orientation information is then conveyed to an onboard controller for automatic speed and steering control of the follower. The study has a number of different aspects including development of a frequency selective surface for the patch development of the radar system for determination of spacing and orientation analysis and development of the control system for speed and steering control in a vehicle following configuration.