Optimal Path Planning using CAMIS: a Continuous Anisotropic Model for Inclined Surfaces
This work addresses path planning for mobile robots on slopes, offering a tunable model to balance energy and stability, but it is incremental as it builds on existing anisotropic planners like the Ordered Upwind Method.
The paper tackled the problem of optimal path planning for ground mobile robots on irregular terrains by developing the Continuous Anisotropic Model for Inclined Surfaces (CAMIS), which accounts for anisotropy due to slopes and allows tuning between energy minimization and stability; simulation tests showed it can be more advantageous than isotropic models in certain slope scenarios, and a field experiment with a skid-steering robot validated its applicability.
The optimal traverse of irregular terrains made by ground mobile robots heavily depends on the adequacy of the cost models used to plan the path they follow. The criteria to define optimality may be based on minimizing energy consumption and/or preserving the robot stability. This entails the proper assessment of anisotropy to account for the robot driving on top of slopes with different directions. To fulfill this demand, this paper presents the Continuous Anisotropic Model for Inclined Surfaces, a cost model compatible with anisotropic path planners like the bi-directional Ordered Upwind Method. This model acknowledges how the orientation of the robot with respect to any slope determines its energetic cost, considering the action of gravity and terramechanic effects such as the slippage. Moreover, the proposed model can be tuned to define a trade-off between energy minimization and Roll angle reduction. The results from two simulation tests demonstrate how, to find the optimal path in scenarios containing slopes, in certain situations the use of this model can be more advantageous than relying on isotropic cost functions. Finally, the outcome of a field experiment involving a skid-steering robot that drives on top of a real slope is also discussed.