Energy-efficient walking over irregular terrain: a case of hexapod robot

Abstract

Adaptive locomotion over difficult or irregular terrain is considered as a superiority feature of walking robotsover wheeled or tracked machines. However, safe foot positioning, body posture and stability, correct legtrajectory, and efficient path planning are a necessity for legged robots to overcome a variety of possibleterrains and obstacles. Without these properties, any walking machine becomes useless. Energy consumptionis one of the major problems for robots with a large number of Degrees of Freedom (DoF). When consideringa path plan or movement parameters such as speed, step length or step height, it is important to choose the mostsuitable variables to sustain long battery life and to reach the objective or complete the task successfully. Wechange the settings of a hexapod robot leg trajectory for overcoming small terrain irregularities by optimizingconsumed energy and leg trajectory during each leg transfer. The trajectory settings are implemented asa part of hexapod robot simulation model and tested through series of experiments with various terrainsof differing complexity and obstacles of various sizes. Our results show that the proposed energy-efficienttrajectory transformation is an effective method for minimizing energy consumption and improving overallperformance of a walking robot.