Department of Large Animal Sciences, Faculty of Health and Medical Science, University of Copenhagen, Taastrup, Denmark.
Sensors (Basel). 2012;12(6):8145-56. doi: 10.3390/s120608145. Epub 2012 Jun 12.
The increased variations of temporal gait events when pathology is present are good candidate features for objective diagnostic tests. We hypothesised that the gait events hoof-on/off and stance can be detected accurately and precisely using features from trunk and distal limb-mounted Inertial Measurement Units (IMUs). Four IMUs were mounted on the distal limb and five IMUs were attached to the skin over the dorsal spinous processes at the withers, fourth lumbar vertebrae and sacrum as well as left and right tuber coxae. IMU data were synchronised to a force plate array and a motion capture system. Accuracy (bias) and precision (SD of bias) was calculated to compare force plate and IMU timings for gait events. Data were collected from seven horses. One hundred and twenty three (123) front limb steps were analysed; hoof-on was detected with a bias (SD) of -7 (23) ms, hoof-off with 0.7 (37) ms and front limb stance with -0.02 (37) ms. A total of 119 hind limb steps were analysed; hoof-on was found with a bias (SD) of -4 (25) ms, hoof-off with 6 (21) ms and hind limb stance with 0.2 (28) ms. IMUs mounted on the distal limbs and sacrum can detect gait events accurately and precisely.
当存在病理学变化时,时间步态事件的变化增加是客观诊断测试的良好候选特征。我们假设使用来自躯干和远端肢体安装的惯性测量单元(IMU)的特征,可以准确、精确地检测到步态事件的蹄上/下和站立。四个 IMU 安装在远端肢体上,五个 IMU 附着在肩部、第四腰椎和骶骨以及左右坐骨结节上方的皮肤背部棘突上。IMU 数据与力板阵列和运动捕捉系统同步。为了比较步态事件的力板和 IMU 计时,计算了准确性(偏差)和精度(偏差的 SD)。从七匹马中收集了数据。分析了 123 个前肢步骤;蹄上的检测偏差(SD)为-7(23)ms,蹄下的检测偏差为 0.7(37)ms,前肢站立的检测偏差为-0.02(37)ms。总共分析了 119 个后肢步骤;蹄上的检测偏差(SD)为-4(25)ms,蹄下的检测偏差为 6(21)ms,后肢站立的检测偏差为 0.2(28)ms。安装在远端肢体和骶骨上的 IMU 可以准确、精确地检测步态事件。