On the Climbing Ability of Passively Suspended Tracked Robots

This article investigates the obstacle-climbing ability of a novel passively articulated robot, Polibot, which is compared to a standard tracked robot using a fixed-wheel configuration. Two test cases are analyzed: the traverse of a single obstacle and the navigation upward along a vertical surface. Both scenarios are analytically solved using a quasistatic Newton–Euler approach. The dynamic equilibrium of the system is also defined using an energetic approach, focusing on the energy loss from the wheel-ground slippage. Understanding the role played by the different energy components contributes to shedding light on the fundamental mechanisms underlying the negotiation of obstacles and highly challenging terrain, in general, by suspended tracked robots. Finally, experimental results are presented to validate the proposed approach in real-world conditions.