Dangol Pravin, Sihite Eric, Ramezani Alireza
Silicon Synapse Lab., Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, United States.
Front Robot AI. 2021 Dec 23;8:770514. doi: 10.3389/frobt.2021.770514. eCollection 2021.
Fast constraint satisfaction, frontal dynamics stabilization, and avoiding fallovers in dynamic, bipedal walkers can be pretty challenging. The challenges include underactuation, vulnerability to external perturbations, and high computational complexity that arise when accounting for the system full-dynamics and environmental interactions. In this work, we study the potential roles of thrusters in addressing some of these locomotion challenges in bipedal robotics. We will introduce a thruster-assisted bipedal robot called . We will capitalize on Harpy's unique design to propose an optimization-free approach to satisfy gait feasibility conditions. In this thruster-assisted legged locomotion, the reference trajectories can be manipulated to fulfill constraints brought on by ground contact and those prescribed for states and inputs. Unintended changes to the trajectories, especially those optimized to produce periodic orbits, can adversely affect gait stability and hybrid invariance. We will show our approach can still guarantee stability and hybrid invariance of the gaits by employing the thrusters in Harpy. We will also show that the thrusters can be leveraged to robustify the gaits by dodging fallovers or jumping over large obstacles.
在动态双足步行机器人中实现快速约束满足、前向动力学稳定以及避免摔倒极具挑战性。这些挑战包括驱动不足、易受外部干扰影响，以及在考虑系统全动力学和环境相互作用时出现的高计算复杂性。在这项工作中，我们研究推进器在解决双足机器人这些运动挑战方面的潜在作用。我们将介绍一种名为 的推进器辅助双足机器人。我们将利用哈耳庇厄独特的设计提出一种无需优化的方法来满足步态可行性条件。在这种推进器辅助的腿部运动中，可以操纵参考轨迹以满足地面接触带来的约束以及针对状态和输入规定的约束。轨迹的意外变化，尤其是那些为产生周期轨道而优化的变化，可能会对步态稳定性和混合不变性产生不利影响。我们将展示我们的方法通过在哈耳庇厄中使用推进器仍能保证步态的稳定性和混合不变性。我们还将表明，可以利用推进器通过躲避摔倒或跨越大型障碍物来增强步态的稳健性。
