scholarly journals An Evaluation of Motion Trackers with Virtual Reality Sensor Technology in Comparison to a Marker-Based Motion Capture System Based on Joint Angles for Ergonomic Risk Assessment

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3145
Author(s):  
Jan P. Vox ◽  
Anika Weber ◽  
Karen Insa Wolf ◽  
Krzysztof Izdebski ◽  
Thomas Schüler ◽  
...  

The reproduction and simulation of workplaces, and the analysis of body postures during work processes, are parts of ergonomic risk assessments. A commercial virtual reality (VR) system offers the possibility to model complex work scenarios as virtual mock-ups and to evaluate their ergonomic designs by analyzing motion behavior while performing work processes. In this study a VR tracking sensor system (HTC Vive tracker) combined with an inverse kinematic model (Final IK) was compared with a marker-based optical motion capture system (Qualisys). Marker-based optical motion capture systems are considered the gold standard for motion analysis. Therefore, Qualisys was used as the ground truth in this study. The research question to be answered was how accurately the HTC Vive System combined with Final IK can measure joint angles used for ergonomic evaluation. Twenty-six subjects were observed simultaneously with both tracking systems while performing 20 defined movements. Sixteen joint angles were analyzed. Joint angle deviations between ±6∘ and ±42∘ were identified. These high deviations must be considered in ergonomic risk assessments when using a VR system. The results show that commercial low-budget tracking systems have the potential to map joint angles. Nevertheless, substantial weaknesses and inaccuracies in some body regions must be taken into account. Recommendations are provided to improve tracking accuracy and avoid systematic errors.

2011 ◽  
Vol 08 (02) ◽  
pp. 275-299 ◽  
Author(s):  
JUNG-YUP KIM ◽  
YOUNG-SEOG KIM

This paper, describes the development of a motion capture system with novel features for biped robots. In general, motion capture is effectively utilized in the field of computer animation. In the field of humanoid robotics, the number of studies attempting to design human-like gaits by using expensive optical motion capture systems is increasing. The optical motion capture systems used in these studies have involved a large number of cameras because such systems use small-sized ball markers; hence the position accuracy of the markers and the system calibration are very significant. However, since the human walking gait is a simple periodic motion rather than a complex motion, we have developed a specialized motion capture system for this study using dual video cameras and large band-type markers without high-level system calibration in order to capture the human walking gait. In addition to its lower complexity, the proposed capture method requires only a low-cost system and has high space efficiency. An image processing algorithm is also proposed for deriving the human gait data. Finally, we verify the reliability and accuracy of our system by comparing a zero moment point (ZMP) trajectory calculated by the motion captured data with a ZMP trajectory measured by foot force sensors.


2017 ◽  
Vol 2017 (0) ◽  
pp. A-36
Author(s):  
Tatsuro Ishizuka ◽  
Tokio Maeda ◽  
Sakura Yamaji ◽  
Yuji Ohgi ◽  
Humiaki Shibayama ◽  
...  

2020 ◽  
Author(s):  
Oliver A Silverson ◽  
Nicole G Cascia ◽  
Carolyn M Hettrich ◽  
Nicholas R Heebner ◽  
Tim L Uhl

Abstract Context: A single clinical assessment device that objectively measures scapular motion in each anatomical plane is not currently available. The development of a novel electric goniometer affords the ability to quantify scapular motion in all three anatomical planes. Objective: Investigate the reliability and validity of an electric goniometer to measure scapular motion in each anatomical plane during arm elevation. Design: Cross-sectional. Setting: Laboratory setting. Patients or Other Participants: Sixty participants (29 females, 31 males) were recruited from the general population. Intervention(s): An electric goniometer was used to record clinical measurements of scapular position at rest and total arc of motion (excursion) during active arm elevation in two testing sessions separated by several days. Measurements were recorded independently by two examiners. In one session, scapular motion was recorded simultaneously with a 14-camera three-dimensional optical motion capture system. Main Outcome Measures: Reliability analysis included examination of clinical measurements for scapular position at rest and excursion during each condition. Both the intra-rater reliability between testing sessions and the inter-rater reliability recorded within the same session were assessed using Intraclass Correlation Coefficients (ICC2,3). The criterion-validity was examined by comparing the mean excursion values of each condition recorded by the electric goniometer to the 3D optical motion capture system. Validity was assessed by evaluating the average difference and root mean square error (RMSE). Results: The between session intra-rater reliability was moderate to good (ICC2,3: 0.628–0.874). The within session inter-rater reliability was moderate to excellent (ICC2,3: 0.545–0.912). The average difference between the electric goniometer and 3D optical motion capture system ranged from −7° to 4° and the RMSE was between 7–10°. Conclusions: The reliability of scapular measurements is best when a standard operating procedure is used. The electric goniometer provides an accurate measurement of scapular excursions in all three anatomical planes during arm elevation.


Sign in / Sign up

Export Citation Format

Share Document