New project page: NAS and CASSR, footstep planning

A new project page presents our two recent footstep planners for humanoids, led by Jiayi Wang: NAS (Humanoids 2024), which computes all the solutions of the contact planning problem to obtain a globally optimal policy, and CASSR (ICRA 2026), an A* search that propagates continuous reachability constraints and plans up to 30 footsteps in under 125 ms. Both come with a video.