Laboratory of Biomechanics and Implant Research, Department of Orthopaedics, Heidelberg University Hospital, Heidelberg, Germany.
Institute of Orthopaedic Research and Biomechanics, Centre for Trauma Research Ulm, Ulm University Medical Centre, Ulm, Germany.
PLoS One. 2022 Jul 11;17(7):e0271349. doi: 10.1371/journal.pone.0271349. eCollection 2022.
Multiple camera systems are widely used for 3D-motion analysis. Due to increasing accuracies these camera systems gained interest in biomechanical research areas, where high precision measurements are desirable. In the current study different measurement systems were compared regarding their measurement accuracy.
Translational and rotational accuracy measurements as well as the zero offset measurements of seven different measurement systems were performed using two reference devices and two different evaluation algorithms. All measurements were performed in the same room with constant temperature at the same laboratory. Equal positions were measured with the systems according to a standardized protocol. Measurement errors were determined and compared.
The highest measurement errors were seen for a measurement system using active ultrasonic markers, followed by another active marker measurement system (infrared) having measurement errors up to several hundred micrometers. The highest accuracies were achieved by three stereo camera systems, using passive 2D marker points having errors typically below 20 μm.
This study can help to better assess the results obtained with different measurement systems. With the focus on the measurement accuracy, only one aspect in the selection of a system was considered. Depending on the requirements of the user, other factors like measurement frequency, the maximum analyzable volume, the marker type or the costs are important factors as well.
多摄像机系统广泛应用于 3D 运动分析。由于精度的提高，这些摄像机系统在生物力学研究领域引起了关注，在这些领域需要高精度的测量。本研究比较了不同测量系统的测量精度。
使用两个参考设备和两种不同的评估算法，对七种不同测量系统的平移和旋转精度以及零位偏移测量进行了测量。所有测量均在相同的实验室、相同的室温下进行。根据标准化协议，用系统测量相同的位置。确定并比较测量误差。
使用主动式超声标记的测量系统的测量误差最大，其次是另一种主动式标记测量系统（红外），其测量误差高达数百微米。使用被动式 2D 标记点的三个立体相机系统具有最高的精度，其误差通常低于 20μm。
本研究有助于更好地评估不同测量系统获得的结果。本研究重点关注测量精度，仅考虑了系统选择中的一个方面。根据用户的要求，其他因素如测量频率、最大可分析体积、标记类型或成本也是重要因素。
