Unstructured Terrain Navigation and Topographic Mapping with a Lowcost Mobile Cuboid Robot Current robotic terrain mapping techniques require expensive sensor suites to construct an environmental representation. In this work, we present a cubeshaped robot that can roll through unstructured terrain and construct a detailed topographic map of the surface that it traverses in real time with low computational and monetary expense. Our approach devolves many of the complexities of locomotion and mapping to passive mechanical features. Namely, rolling movement is achieved by sequentially inflating latex bladders that are located on four sides of the robot to destabilize and tip it. Sensing is achieved via arrays of fine plastic pins that passively conform to the geometry of underlying terrain, retracting into the cube. We developed a topography by shade algorithm to process images of the displaced pins to reconstruct terrain contours and elevation. We experimentally validated the efficacy of the proposed robot through object mapping and terrain locomotion tasks.

Mapping for Planetary Rovers from Terramechanics Perspective In an autonomous scientific exploration system, the terrain map generated from mapping process integrates sensing information from multiple aspects and lays the base for decision making processes. With the increasing challenges in planetary exploration, equipping planetary rovers with the principles of terramechanics is becoming more and more common, especially on rough or intricate terrain. However, it is difficult for conventional maps with elevation information only to reflect terrain mechanical properties, which play important roles in terramechanicsbased simulation or motion control. This study extracts the dominant parameters in terrain bearing and shearing models, and presents a multilayered grid map with fundamental geometric and mechanical elements. A corresponding mapping scheme based on dense visual input is designed to reconstruct elevation in the map and predict terrain mechanical parameters of the entire visual field. Experiments are conducted to verify the practicability of the approach proposed in a Mars emulation yard with a rover prototype.