This paper exposes a control architecture enabling rehabilitation of walking impaired patients with the lower-limb exoskeleton Atalante. Atalante's control system is modified to allow the patient to contribute to the walking motion through their efforts. Only the swing leg degree of freedom along the nominal path is relaxed. An online trajectory optimization checks that the muscle forces do not jeopardize stability. The optimization generates reference trajectories that satisfy several key constraints from the current point to the end of the step. One of the constraints requires that the center or pressure remains inside the support polygon, which ensures that the support leg subsystem successfully tracks the reference trajectory. As a result of the presented works, the robot provides a non-zero force in the direction of motion only when required, helping the patient go fast enough to maintain balance (or preventing him from going too fast). Experimental results are reported. They illustrate that variations of $\pm$50% of the duration of the step can be achieved in response to the patient's efforts and that many steps are achieved without falling. A video of the experiments can be viewed at https://youtu.be/_1A-2nLy5ZE

翻译：本文提出了一种控制架构，用于实现下肢外骨骼Atalante对步行障碍患者的康复治疗。对Atalante的控制系统进行了改进，允许患者通过自身发力参与步行运动，仅放松了摆动腿沿标称路径的自由度。在线轨迹优化确保肌肉力不会危及稳定性，该优化生成从当前点至步态终点满足多项关键约束的参考轨迹。其中一项约束要求压力中心始终位于支撑多边形内，从而保证支撑腿子系统能成功跟踪参考轨迹。研究结果表明，机器人仅在必要时沿运动方向施加非零力，帮助患者以足够快的速度维持平衡（或防止其速度过快）。实验结果表明，根据患者发力情况，步态时长可实现±50%的变化，且多次步行动作未发生跌倒。实验视频可见于https://youtu.be/_1A-2nLy5ZE。