An Instrumented Wheel to Measure the Wheel–Terrain Interactions of Planetary Robotic Wheel-on-Limb System on Sandy Terrains

Understanding the wheel–terrain interaction (WTI) is of great importance to improve the traversability of the planetary rovers. In this article, the design and implementation of an instrumented wheel (IW) for characterizing the WTIs are presented. Such an IW is the key technique of the wheel-on-limb detection (WOLD) system that aims for the forward terrain sensing and traversability prediction before the traversal of the rover. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">In situ</i> measurements of the WTI forces, wheel velocity, and wheel contact angle, as well as the wheel sinkage, can be achieved via such an IW. Experimental calibration is first implemented to guarantee the IW performance. Then, field tests in the representative environments are conducted to verify the measured parameters of WTIs. It has indicated that such a system concept would be potentially applicable in the future long-safe planetary traverses concerning the rover payloads development and functional validation.