Control Strategies For A Roll Simulator For Recreational Off-Highway Vehicles

Control strategies for a two degree-of-freedom roll simulator are presented. The simulator consists of a sled-platform assembly that translates along rails. A Recreational Off-Highway Vehicle (ROV) is mounted on the platform, which has the freedom to rotate about a roll axis. The roll axis is nominally perpendicular to the rails and parallel to the ground plane. This can be altered by using the third degree-of-freedom (static) that yaws the platform and changes the angle of the roll axis with respect to the rails. This angle is incorporated to achieve the appropriate acceleration vector. The assembly accelerates to a desired speed via a hydraulic motor and is decelerated with a magnetic particle brake at a specified deceleration level (nominally 0.7 g).Coordination of two mechanical systems proved to be difficult due to inherent lags in both systems. The cable-drum system created many problems as tension needs to be maintained in the cable at all times. Using only knowledge of the physical system, results showed reasonable agreement with desired levels. The roll motions showed excellent correlation with the desired levels.