Search Results

Synthetic Automotive Virtual Environment (SAVE) is a research program to develop useful descriptions of high-speed, loose-surface ground vehicle interface dynamics and to apply those findings to synthetic training environments, autonomous vehicle development, active safety systems development, and to the construction of safer roads. Live training for accident avoidance through vehicle control is problematic due to the dangers of having unskilled drivers in critical situations. Furthermore, for a driver to perform the critical skills well in an unexpected driving situation requires that their response become automatic through muscle memory development. A simulator environment removes the student from the potentially dangerous consequences of these situations and allows for repetitive training to develop muscle memory.

Tire cornering forces are often measured in the laboratory on a high-friction surface and little information exists on the nature of cornering on other surfaces. Thus, the impact of winter roads on vehicle behavior is difficult to fully capture in vehicle dynamics simulations. The CRREL (Cold Regions Research and Engineering Laboratory) Instrumented Vehicle was used to measure cornering forces on winter surfaces. The vehicle was instrumented for forces, speeds, and a variety of other measures. Tests were performed at the Keweenaw Research Center in Northern Michigan, during February 2005, and included measurements on ice, packed snow, and undisturbed snow. Packed snow density was 0.5 g/cm3 and loose snow densities ranged from 0.07 to 0.23 g/cm3 with depths from 5 to 23 cm. The test technique involved towing the vehicle in a straight line while sweeping the steering angle from zero to approximately 17 degrees both left and right.

Traction on winter surfaces was measured using three test vehicles, each designed to measure traction for a different purpose: vehicle mobility research (CRREL instrumented vehicle), commercial tire testing (Uniroyal-Goodrich traction tester) and airport runway safety (SAAB friction tester). The traction measured with each method is comparable, but there are systematic differences due to the effects of the surface materials and test and analysis techniques. This comparison serves as the basis for collaboration between the various traction and data analyses for traction testing and evaluation.