Foothold Planning and Gait Generation for a Hexapod Robot Traversing Terrains with Forbidden Zones

One of the primary advantage of walking machines is their inherent capacity to operate in different terrains. However, it is necessary a locomotion system for planning in advance future footholds, and to modify the robot gait in order to maintain the platform stability. Several locomotion systems have been developed for rectangular hexapod robots, in this work a system for radially a symmetric hexapod robot is presented. It includes a module for planning the next foothold, which takes information from the robot motion and terrain obstacles, and send signals to the global controller with the modifications needed on legs trajectories. These actions demand a new coordination between moving legs, while maintaining stability. The described system was coupled with two gait pattern generators for legs coordination over terrains with forbidden zones. The locomotion system was tested on a circular hexapod robot model using a dynamic simulation software. Results from simulations show that the proposed algorithm worked successfully, with a less than 1% of error.