Demo 2003 Highway Tests Begin

PATH researchers traveled to San Diego on July 27-28 for dynamic testing of a tractor-trailer combination and a transit bus on the Interstate-15 HOV lanes in preparation for Demo 2003.

The truck is instrumented with various sensors and data acquisition systems to record information on vehicle motion, engine, and transmission states with the vehicle under different driving and loading conditions. It was driven manually throughout the two days of testing. The options of speed cruise control, engine braking, and transmission retarder were activated selectively during the test runs. The load was changed in several stages, from a full load of about 40,000 lbs to an empty trailer. Radio devices and antennas for vehicle-to-vehicle communication systems were also tested to explore their workable range and data integrity in the demo environment.

The PATH Demo development team and Caltrans personnel, supported by San Diego Transit with an articulated 60-ft bus, also experimented with various bus maneuvers in the South Control Yard to explore potential bus stop locations and bus stop design for the demo. A special chalk-dispensing apparatus was installed on a 40-ft bus to automatically trace bus maneuvers on the ground. The PATH Demo team will use the information collected to design the Demo bus stop and bus docking maneuvers.

In conjunction with the Demo 2003 experiments, a number of tests were also conducted for Caltrans-sponsored Task Order 4234 (PI: Prof. T-C Tsao and Prof. A. Stephanopolou) and TO 4235 (PI: Prof. C. Gerdes), which are AVCSS projects on various studies of heavy-duty trucks.

The experiments were successful and provided the PATH Demo team with a rich set of vehicle performance data, which will be the foundation for further developments in vehicle instrumentation and control algorithms. The PATH Demo team is planning to conduct additional testing in August 2002 at Crow's Landing after further hardware and software developments.