Chen Ji, Hochstein Jon, Kim Christina, Damiano Diane, Bulea Thomas
Functional and Applied Biomechanics Section, Rehabilitation Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD 20892 USA.
Proc IEEE RAS EMBS Int Conf Biomed Robot Biomechatron. 2018 Aug;2018:37-42. doi: 10.1109/biorob.2018.8487195. Epub 2018 Oct 11.
Exoskeleton assisted gait training in children with cerebral palsy (CP) offers the potential to increase therapy dosage and intensity compared to current approaches. Here, we report the design and characterization of a pediatric knee exoskeleton for gait training outside of a clinical environment. A multi-layered closed loop control system and a microcontroller based data acquisition system were implemented to provide individualized control approaches and achieve device portability for home use. Step response tests show the averaged 90% rise time was 45 ms for 5 Nm, 35 ms for 10 Nm, 40 ms for 15 Nm. The gain-limited closed-loop torque bandwidth was about 9 Hz with a 9 Nm amplitude chirp in knee flexion and extension. The actuator has low output impedance (<0.5 Nm) at low frequencies expected during use. Future work will investigate the long term effects of providing children with CP knee extension assistance during daily walking on gait biomechanics with, and without, the device.
与目前的方法相比，外骨骼辅助脑瘫（CP）儿童进行步态训练有可能增加治疗剂量和强度。在此，我们报告一种用于临床环境外步态训练的儿童膝关节外骨骼的设计与特性。实施了多层闭环控制系统和基于微控制器的数据采集系统，以提供个性化控制方法，并实现设备便于在家中使用的便携性。阶跃响应测试表明，对于5 Nm，平均90%上升时间为45 ms；对于10 Nm，为35 ms；对于15 Nm，为40 ms。在膝关节屈伸中，增益受限的闭环扭矩带宽约为9 Hz，幅度啁啾为9 Nm。该致动器在使用期间预期的低频下具有低输出阻抗（<0.5 Nm）。未来的工作将研究在有和没有该设备的情况下，在日常行走期间为CP儿童提供膝关节伸展辅助对步态生物力学的长期影响。
