A Study of Vicon System Positioning Performance

Abstract

Motion capture setups are used in numerous fields. Studies based on motion capture data can be found in biomechanical, sport or animal science. Clinical science studies include gait analysis as well as balance, posture and motor control. Robotic applications encompass object tracking. Today’s life applications includes entertainment or augmented reality. Still, few studies investigate the positioning performance of motion capture setups. In this paper, we study the positioning performance of one player in the optoelectronic motion capture based on markers: Vicon system. Our protocol includes evaluations of static and dynamic performances. Mean error as well as positioning variabilities are studied with calibrated ground truth setups that are not based on other motion capture modalities. We introduce a new setup that enables directly estimating the absolute positioning accuracy for dynamic experiments contrary to state-of-the art works that rely on inter-marker distances. The system performs well on static experiments with a mean absolute error of 0.15 mm and a variability lower than 0.025 mm. Our dynamic experiments were carried out at speeds found in real applications. Our work suggests that the system error is less than 2 mm. We also found that marker size and Vicon sampling rate must be carefully chosen with respect to the speed encountered in the application in order to reach optimal positioning performance that can go to 0.3 mm for our dynamic study.

On-field player workload exposure and knee injury risk monitoring via deep learning

“…The preparation phase was necessary to ensure the integrity of the marker trajectories and force plate analog channels, and to limit the impact of manual errors that may have propagated through the original data capture pipeline [35,42]. First, the data mining relied on trials with the eight required marker trajectories being contiguous and labeled, together with associated KJM, and force plate channel data present throughout the entire stance phase.…”

Combining a hierarchical task network planner with a constraint satisfaction solver for assembly operations involving routing problems in a multi-robot context

“…Within the test bed, localization of the robots is given by the Vicon motion tracking system (Vicon motion systems Inc., Oxford, United Kingdom) with millimeter precision. In the study done by Merriaux et al, 34 it has been proven that the Vicon system can achieve errors below 2 mm at common speeds, and below 1 mm for static objects. For the simulations, the Robot Operating System (ROS), the global coordinate system is used.…”

A review of computational approaches for evaluation of rehabilitation exercises

“…A dedicated software program utilizes trigonometrical relations among the markers in captured images and the locations of the cameras to calculate the positions and orientations of the body joints. Many studies confirmed the excellent positioning performance of these motion capture systems in both static and dynamic tests [95]- [97]. As a result, optical tracking systems are regarded as the gold standard for verifying tracking reliability of other motion sensors [76], [98]- [100].…”

“…In general, feature engineering involves feature extraction and feature selection. In many related works, feature engineering is performed manually based on authors' understanding of human movements [33]- [37], [54], [97], [98], [126], [127]. For example, in [34], underarm angles and Euclidean distance between the elbows were used to describe the lifting of the arms.…”

“…Only give a overall score for exercise performance [39]- [41], [52], [53], [55], [57], [96], [97], [103], [128], [138], [140], [143], [145], [148], [156], [190], [196]…”