El-Sayed Amr M, Hamzaid Nur Azah, Abu Osman Noor Azuan
Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia.
Sensors (Basel). 2014 Dec 10;14(12):23724-41. doi: 10.3390/s141223724.
Alternative sensory systems for the development of prosthetic knees are being increasingly highlighted nowadays, due to the rapid advancements in the field of lower limb prosthetics. This study presents the use of piezoelectric bimorphs as in-socket sensors for transfemoral amputees. An Instron machine was used in the calibration procedure and the corresponding output data were further analyzed to determine the static and dynamic characteristics of the piezoelectric bimorph. The piezoelectric bimorph showed appropriate static operating range, repeatability, hysteresis, and frequency response for application in lower prosthesis, with a force range of 0-100 N. To further validate this finding, an experiment was conducted with a single transfemoral amputee subject to measure the stump/socket pressure using the piezoelectric bimorph embedded inside the socket. The results showed that a maximum interface pressure of about 27 kPa occurred at the anterior proximal site compared to the anterior distal and posterior sites, consistent with values published in other studies. This paper highlighted the capacity of piezoelectric bimorphs to perform as in-socket sensors for transfemoral amputees. However, further experiments are recommended to be conducted with different amputees with different socket types.
由于下肢假肢领域的快速发展，用于假肢膝关节开发的替代传感系统如今越来越受到关注。本研究介绍了将压电双晶片用作经股骨截肢者的插座内传感器。在校准过程中使用了英斯特朗材料试验机，并对相应的输出数据进行了进一步分析，以确定压电双晶片的静态和动态特性。该压电双晶片在0-100 N 的力范围内，在较低假肢应用中显示出合适的静态工作范围、重复性、滞后性和频率响应。为了进一步验证这一发现，对一名经股骨截肢者进行了实验，使用嵌入插座内的压电双晶片测量残肢/插座压力。结果表明，与前远端和后侧部位相比，在前近端部位出现了约27 kPa 的最大界面压力，这与其他研究发表的值一致。本文强调了压电双晶片作为经股骨截肢者插座内传感器的能力。然而，建议对不同类型插座的不同截肢者进行进一步实验。
