# On-line and on-board planning and perception for quadrupedal locomotion

## TL;DR

This paper introduces an online, on-board planning method for quadrupedal robots that decomposes locomotion into body and footstep planning, using lattice representations and A* search to generate feasible, versatile movements over challenging terrains.

## Contribution

It presents a novel online planning approach combining body and footstep planning with lattice representation and A* search for quadrupedal locomotion.

## Key findings

- Demonstrated successful planning over challenging terrains
- Plans are computed on-line and on-board in real-time
- The approach ensures feasible and versatile movements

## Abstract

We present a legged motion planning approach for quadrupedal locomotion over challenging terrain. We decompose the problem into body action planning and footstep planning. We use a lattice representation together with a set of defined body movement primitives for computing a body action plan. The lattice representation allows us to plan versatile movements that ensure feasibility for every possible plan. To this end, we propose a set of rules that define the footstep search regions and footstep sequence given a body action. We use Anytime Repairing A* (ARA*) search that guarantees bounded suboptimal plans. Our main contribution is a planning approach that generates on-line versatile movements. Experimental trials demonstrate the performance of our planning approach in a set of challenging terrain conditions. The terrain information and plans are computed on-line and on-board.