In this work, the joint-control strategy is presented for the humanoid robot, PANDORA, whose structural components are designed to be compliant. As opposed to contemporary approaches which design the elasticity internal to the actuator housing, PANDORA's structural components are designed to be compliant under load or, in other words, structurally elastic. To maintain the rapid design benefit of additive manufacturing, this joint control strategy employs a disturbance observer (DOB) modeled from an ideal elastic actuator. This robust controller treats the model variation from the structurally elastic components as a disturbance and eliminates the need for system identification of the 3D printed parts. This enables mechanical design engineers to iterate on the 3D printed linkages without requiring consistent tuning from the joint controller. Two sets of hardware results are presented for validating the controller. The first set of results are conducted on an ideal elastic actuator testbed that drives an unmodeled, 1 DoF weighted pendulum with a 10 kg mass. The results support the claim that the DOB can handle significant model variation. The second set of results is from a robust balancing experiment conducted on the 12 DoF lower body of PANDORA. The robot maintains balance while an operator applies 50 N pushes to the pelvis, where the actuator tracking results are presented for the left leg.

翻译：本文针对结构组件设计为柔顺的人形机器人PANDORA提出了一种关节控制策略。与当前将弹性设计在驱动器外壳内部的方法不同，PANDORA的结构组件被设计为在负载下保持柔顺性，即具有结构弹性。为保持增材制造在快速设计方面的优势，该关节控制策略采用了基于理想弹性驱动器建模的扰动观测器（DOB）。该鲁棒控制器将结构弹性组件引起的模型变化视为扰动，从而无需对3D打印部件进行系统辨识。这使得机械设计工程师能够在无需关节控制器持续调参的情况下，迭代优化3D打印连杆机构。本文通过两组硬件实验结果验证了控制器的有效性：第一组实验在理想弹性驱动器测试台上进行，驱动一个未建模的、带有10公斤质量的单自由度加权摆锤，结果证明DOB能够处理显著的模型变化；第二组实验在PANDORA的12自由度下半身进行鲁棒平衡测试，当操作者对骨盆施加50N推力时，机器人仍能保持平衡，文中同时给出了左腿驱动器的跟踪结果。