Video-based Motion Analysis Research Articles

Validation of a Hand/Wrist Electromechanical Goniometer

This paper describes a new hand/wrist electromechanical goniometer that measures wrist angle, velocity, and acceleration in the radial/ulnar and flexion/extension planes. The research objectives of this paper were to validate the angle and motion measures from this goniometer. The results of this research show that the coefficient of variation of the angle measured by the goniometer and the angle measured by a video-based Motion Analysis system was 3%. By smoothing the voltage data three times in software, the goniometer estimated well the velocity and acceleration measures under controlled dynamic conditions. Three smoothing repetitions appear to be the best smoothing regimen for the goniometer because it reduced signal noise while still maintaining the sensitivity of the velocity and acceleration output. Overall, the goniometer is an easy-to-use, accurate system of measuring wrist angle and motion. This goniometer will be used to build a database of wrist motion in industrial tasks.

New technique for acquiring three-dimensional orofacial nonspeech movements.

A new video-based motion analysis system is described that permits acquisition of kinematic patterns from multiple structures (upper lip, lower lip, and jaw), movement patterns to be captured in three dimensions, and acquisition of non-speech orofacial movement patterns without restricting natural head motion. The importance of acquiring three-dimensional lip and jaw movements during nonspeech (e.g., oral opening-closing and chewing motions) movements is emphasized.