Vicon motion capture system mxt series

The VICON^® Motion Capture System (MXT series, Oxford Metrics, Ltd., Oxford, UK) includes 8 infrared cameras and has dedicated hardware that uses them to locate coordinates of location points. The VICON^® system also includes a counter-reflection marker depending on the infrared signal from the infrared strobe of each camera. The torso and lower limb landmarks consist of four attached markers (14 mm in diameter), as well as the seventh cervical spine (C7), eighth thoracic spine (T8), and xiphoid processes of the jugular and sternum. In addition, two cross-shaped clusters consisting of four markers were attached to the thigh and shank, and one axis of the cross was measured due to alignment with the femur or tibia axis. In addition, each camera analyzed the 3D position of all markers in the 100 Hz range, and the joint angle was calculated in a similar way to measurements based on a multi-view motion capture system. The body coordinates, femoral axis, and tibia axis vectors were set using the position points of each marker, and the body coordinates were set according to Wu et al. [21 (link)]. Cross-shaped clusters were used for femur and tibia axis vectors, while MATLAB R2018A (The Mathworks, Inc., Natick, MA, USA) was used for joint angle measurements.

A Vicon motion capture system (MX T series, Oxford Metrics, Ltd., Oxford, UK) has proprietary hardware to capture the coordinates of the positioning points using eight infrared (IR) cameras. This system also requires retro-reflective markers to the emitted IR light signal from the IR strobe of each camera. Four markers (14-mm in diameter) were attached to the trunk and lower extremity landmarks, including the seventh cervical vertebrae (C7), the eighth thoracic vertebrae (T8), the jugular notch, and the xiphoid process of the sternum. Two cross-shaped clusters consisting of four markers were attached to the thigh and the shank. One axis of the cross was aligned to the femoral or tibial shaft. Each camera captured the three-dimensional locations of all markers at 100 Hz. Joint angles were calculated in a similar manner as the analysis based on the multi-view motion capture system, however, the trunk coordinate, the femoral shaft, and the tibial shaft vector were defined differently using the positioning points of each marker. The trunk coordinate was obtained as described by Wu and colleague’s methods (Wu et al., 2005 (link)). The femoral and tibial shaft vectors were obtained using a cross-shaped cluster. The joint angle analysis was conducted using MATLAB R2018A (The Mathworks, Inc., Natick, MA, USA).