Variable stiffness locomotion with guaranteed stability for quadruped robots traversing uneven terrains
| Autor: | Xinyuan Zhao, Yuqiang Wu, Yangwei You, Arturo Laurenzi, Nikos Tsagarakis |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2022 |
| Předmět: | |
| Zdroj: | Frontiers in Robotics and AI, Vol 9 (2022) |
| Druh dokumentu: | article |
| ISSN: | 2296-9144 83012451 |
| DOI: | 10.3389/frobt.2022.874290 |
| Popis: | Quadruped robots are widely applied in real-world environments where they have to face the challenges of walking on unknown rough terrains. This paper presents a control pipeline that generates robust and compliant legged locomotion for torque-controlled quadruped robots on uneven terrains. The Cartesian motion planner is designed to be reactive to unexpected early and late contacts using the estimated contact forces. Moreover, we present a novel scheme of optimal stiffness modulation that aims to coordinate desired compliance and tracking performance. It optimizes joint stiffness and contact forces coordinately in a quadratic programming (QP) formulation, where the constraints of non-slipping contacts and torque limits are imposed as well. In addition, the issue of stability under variable stiffness control is solved by imposing a tank-based passivity constraint explicitly. We finally validate the proposed control pipeline on our quadruped robot CENTAURO in experiments on uneven terrains and, through comparative tests, demonstrate the improvements of the variable stiffness locomotion. |
| Databáze: | Directory of Open Access Journals |
| Externí odkaz: |
|