Frey Martin, Colombo Gery, Vaglio Martino, Bucher Rainer, Jörg Matthias, Riener Robert
Swiss Federal Institute of Technology, CH-8092 Zurich, Switzerland.
IEEE Trans Neural Syst Rehabil Eng. 2006 Sep;14(3):311-21. doi: 10.1109/TNSRE.2006.881556.
A novel mechatronic body weight support (BWS) system has been developed to provide precise body weight unloading for patients with neurological or other impairments during treadmill training. The system is composed of a passive elastic spring element to take over the main unloading force and an active closed-loop controlled electric drive to generate the exact desired force. Both force generating units, the passive spring and the active electric drive, act on the patient via a polyester rope connected to a harness worn by the patient. The length of the rope can be adjusted with an electric winch to adapt the system to different patient sizes. The system is fully computer controlled. At unloading loads of up to 60 kg and walking speeds of up to 3.2 km/h, the mean unloading error and the maximum unloading error of the presented BWS system was less than 1 and 3 kg, respectively. The performance was compared with those of two purely passive BWS systems currently being used by most other rehabilitation groups. This comprised counterweight systems and static BWS systems with fixed rope lengths. Counterweight systems reached mean and maximum unloading errors of up to 5.34 and 16.22 kg, respectively. The values for the static BWS were 11.02 kg and 27.67 kg, respectively. The novel mechatronic BWS system presented in this study adjusts desired unloading changes of up to 20 kg within less than 100 ms. Thus, not only constant BWS, but also gait cycle dependent or time variant oscillations of the desired force can be realized with high accuracy. Precise and constant unloading force is believed to be an important prerequisite for BWS gait therapy, where it is important to generate physiologically correct segmental dynamics and ground reaction forces. Thus, the novel BWS system presented in this paper is an important contribution to maximize the therapeutic outcome of human gait rehabilitation.
一种新型机电一体化体重支持（BWS）系统已被开发出来，用于在跑步机训练期间为患有神经或其他损伤的患者提供精确的体重卸载。该系统由一个被动弹性弹簧元件和一个主动闭环控制的电动驱动器组成，被动弹性弹簧元件承担主要卸载力，主动闭环控制的电动驱动器产生精确的所需力。两个力产生单元，即被动弹簧和主动电动驱动器，通过一根聚酯绳作用于患者，该聚酯绳连接到患者佩戴的背带上。绳子的长度可以通过电动绞盘进行调节，以使系统适应不同患者的体型。该系统完全由计算机控制。在所展示的BWS系统中，在卸载负荷高达60千克且步行速度高达3.2千米/小时的情况下，平均卸载误差和最大卸载误差分别小于1千克和3千克。将该系统的性能与目前大多数其他康复小组使用的两种纯被动BWS系统的性能进行了比较。这包括配重系统和固定绳长的静态BWS系统。配重系统的平均卸载误差和最大卸载误差分别高达5.34千克和16.22千克。静态BWS系统的相应值分别为11.02千克和27.67千克。本研究中展示的新型机电一体化BWS系统在不到100毫秒的时间内就能调节高达20千克的所需卸载变化。因此，不仅可以实现恒定的BWS，还能高精度地实现与步态周期相关或随时间变化的所需力振荡。精确且恒定的卸载力被认为是BWS步态治疗的一个重要前提，在步态治疗中，产生生理上正确的节段动力学和地面反作用力很重要。因此，本文展示的新型BWS系统对最大化人类步态康复的治疗效果做出了重要贡献。
