MacLean Mhairi K, Ferris Daniel P
J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Building 1275 Center Drive, Gainesville, FL 32611.
J Med Device. 2020 Dec 1;14(4):045001. doi: 10.1115/1.4047996. Epub 2020 Sep 3.
Walking with bodyweight support is a vital tool for both gait rehabilitation and biomechanics research. There are few commercially available bodyweight support systems for overground walking that are able to provide a near constant lifting force of more than 50% bodyweight. The devices that do exist are expensive and are not often used outside of rehabilitation clinics. Our aim was to design, build, and validate a bodyweight support device for overground walking that: (1) cost less than $5000, (2) could support up to 75% of the users' bodyweight (BW), and (3) had small (±5% BW) fluctuations in force. We used pairs of constant force springs to provide the constant lifting force. To validate the force fluctuation, we recruited eight participants to walk at 0.4, 0.8, 1.2, and 1.6 m/s with 0%, 22%, 46%, and 69% of their bodyweight supported. We used a load cell to measure force through the system and motion capture data to create a vector of the supplied lifting force. The final prototype cost less than $4000 and was able to support 80% of the users' bodyweight. Fluctuations in vertical force increased with speed and bodyweight support, reaching a maximum of 10% at 1.6 m/s and 69% BW support.
借助体重支持进行行走是步态康复和生物力学研究的重要工具。市面上可供户外行走使用的体重支持系统很少，能够提供超过体重50%的近乎恒定的提升力。现有的此类设备价格昂贵，且在康复诊所之外并不常用。我们的目标是设计、制造并验证一种用于户外行走的体重支持设备，该设备要满足以下几点：（1）成本低于5000美元；（2）能够支撑使用者体重的75%；（3）力的波动较小（±5%体重）。我们使用成对的恒力弹簧来提供恒定的提升力。为了验证力的波动情况，我们招募了8名参与者，让他们分别以0.4、0.8、1.2和1.6米/秒的速度行走，分别给予其体重0%、22%、46%和69%的支持。我们使用一个测力传感器来测量通过该系统的力，并利用动作捕捉数据创建所提供提升力的矢量。最终的原型成本低于4000美元，能够支撑使用者体重的80%。垂直力的波动随着速度和体重支持比例的增加而增大，在速度为1.6米/秒且体重支持比例为69%时达到最大值10%。
