Design and Control of a Bipedal Robot

Details

Supervisors

Jungers, Raphaël M. ; Wielant, François

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil électromécanicien, à finalité spécialisée: mécatronique

Abstract

This study investigates the design and control procedures for bipedal walking, with a specific focus on the application of Zero Moment Point (ZMP) based control. A thorough review of control strategies in bipedal robots reveals the significance of ZMP-based control as a primal method. The chosen algorithm serves as a complement to another project that focuses on the development of a new control technique called 'abstraction'. The main objective of this research is to develop an effective ZMP-based controller that ensures stable and robust locomotion for a bipedal robot within a controlled environment. This controller will later serve as a valuable benchmark for comparison and evaluation. The research primarily focuses on the design and implementation of the controller, accompanied by the creation of a new simulation environment specifically tailored for testing and benchmarking the newly proposed controller. Drawing upon existing literature on control methods in bipedal robots, a novel control algorithm is proposed by integrating various techniques available, including foot planner, swing foot, reference ZMP calculation, Centre of Mass (CoM) trajectory generation, inverse kinematics, and feedback control. Extensive simulations are conducted using a dynamic bipedal robot model to validate the effectiveness of the proposed controller. The simulations encompass diverse walking scenarios, such as straight walking and circular motion. The performance evaluation of the controller considers factors such as walking speed, energy efficiency, and trajectory tracking. The simulation results demonstrate that the developed ZMP-based controller achieves stable walking at a maximal speed of 0.235 m/s for straight motion and 0.163 m/s for circular trajectory within a controlled environment and without ZMP feedback. However, the inclusion of ZMP feedback to enhance performance and position tracking reveals unanticipated control issues that remain unresolved at this stage. This research significantly contributes to the field of bipedal robotics by offering a comprehensive analysis and implementation of a ZMP-based controller for an eight-degree-of-freedom bipedal robot. The result provides valuable insights into the design considerations and challenges associated with developing effective control strategies for bipedal locomotion.