Grouser wheel high-speed traction performance: DEM simulation and experimental result

This study focuses on the locomotion characteristics of a high-speed lunar exploration rover. We conduct single-wheel tests under high-speed conditions and provide detailed results from force measurements from both approaches (experiment and simulation). Three types of wheels are prepared: no grouser, low grouser, and high grouser, and their traction performance is compared. The testbed allows speeds of 1 m/s, which is about a hundred times faster than conventional exploration speeds. We also have developed a Discrete Element Method (DEM) simulator to reproduce the same behavior of the experimental testbed. We calculated traction coefficient and traction efficiency for variable slip ratios, and these are evaluated as traction performance. Both results of the experiment and simulation revealed a trend where traction performance decreases as driving velocity increases. Each performance exhibited substantial dependence on not only the slip ratio but also the magnitude of the wheel circumference velocity. Additionally, we confirmed the effectiveness of grouser wheels even at high speeds by evaluating different height of wheels. Finally, A detailed comparison of the experimental results and simulations suggested that more accurate matching could be achieved by optimizing the contact parameters between the wheel and the particles.