Development of a Video Analysis Software for Biomechanics Education

Abstract A standard biomechanics course ought to cover both 1) tissue mechanics that requires a mechanical testing on biological tissue (in-vitro test) and 2) biomechanics of body motion that requires body motion analysis (in-vivo test). These requirements can lead to a significant financial investment in laboratory space, material testing machine, and motion analysis system. As a result, courses of biomechanics often result in a “chalk and board” lecture without hands-on experiments for students. To resolve the challenge confronting the expenses for biomechanics courses, we have modified the previously developed virtual mechanics laboratory (VML) software, which allows users to analyze digital video images captured from a moving body and/or deforming tissues, with a well-developed digital image analysis algorithm. Originally, VML was developed to as the supplemental virtual experimental tool for Dynamics and Mechanics of material courses. A new data matching module is created and added for the application of biomechanics education. In addition to the software modification, we have created new experiment protocols to achieve both mechanical testing on biological tissue and body motion analysis with the software. The VML software consists of following four modules: 1) Video edit module: User will be able edit the length of captured video to a proper length. 2) Dynamics module: User will be able to conduct motion/pixel tracking with an algorithm termed “Digital Image Correlation”. Measured data (displacement and angle change) can be exported as a EXCEL format data for analysis. 3) Mechanics of material module: User will be able to select a region of interest (ROI) in a video image (digital camera video or medical ultrasound video) captured from the deforming tissue. This module will evaluate the tissue deformation (strains). The measured data (strains) can be exported for analysis. 4) Data matching module: User will be able to match (synchronize) the data collected from different testing devices with a technique termed “least square correlation”. The data matching module makes the in-vivo analysis possible. For example, user can simultaneously video record 1) the body motion with a digital camera and 2) in-vivo tissue deformation with a medical ultrasound (B mode ultrasound video) at the time of experiment. Subsequently, user will be able to match two data deduced from two different modules, e.g. angle changes of a foot and tissue strain of Achilles tendon for further analysis. Following the development of VML software, three types of experiment protocols have been drafted. a). Motion analysis protocol: 1) Capture video images of the body motion with a digital camera. 2) Edit the video length in edit module and conduct motion tracking to evaluate the displacement/angle of body parts and export data. 3) Complete the motion analysis utilizing the collected data. b). In vitro tissue mechanical testing protocol: 1) Mount a tissue sample on the tester and capture a video image of a deforming tissue with a digital camera or an ultrasound. 2) Conduct ROI tracking to evaluate tissue deformation 3) Synchronize tissue deformation and applied-force recorded from tester and export data. 4) Evaluate tissue properties using collected data. c). In vivo tissue properties evaluation test protocol: 1) Capture a video image of a body motion to ultrasound image of a deforming tissue. 2) Conduct motion analysis and tissue deformation analysis by using dynamics and mechanical of material module. 3) Synchronize two data deduced in step 2) and export data. 4) Evaluate tissue properties. The VML software and the new experiment protocols will be tested in the brand-new biomechanics course at University of XXXXXX starting in Fall-semester 2020. Because Biomechanics course has never been offered at our university, the efficacy of new software and experiment protocols cannot be examined by conducting statistical analysis on grades of past and new students. Instead, we plan to 1) compare the scores of the quizzes administered at pre- (post- lecture) and post- laboratory and 2) conduct survey among students to check the efficacy of the VML software and experiment protocol.