High-Speed Cross-Polarized Imaging Setup for Tracking Tendon Collagen Fiber Realignment: A Labview Control System


Engineering and Applied Sciences


Fairhill Professor of Orthopaedic Surgery and Professor of Bioengineering

Project Summary

Tendons connect two very different types of tissue: muscle and bone. Their structure, comprised mainly of intricate collagen fibers, allows tendons to translate the contractile force of muscle into movement of bones. However, injury to these tissues makes for a difficult repair and regeneration process. Therefore, during this past summer I devised a method to better characterize collagen fiber realignment during tensile mechanical testing under Dr. Louis Soslowsky in the McKay Orthopaedic Research Laboratory.

This project entailed creating a Labview program (visual programming language) that would control a stepper motor, camera, and Instron mechanical testing device. The stepper motor rotates polarized plates set on an axis oriented 90 degrees with respect to each other while the camera takes images of the testing sample at high frame rates. These events occur simultaneously while the Instron is applying load (along the vertical axis) to the tendon. The user has the option to trigger starting of the motor via pushbutton while the Instron sends signals through a data acquisition device (DAQ) to trigger capturing of images. Thus, the images collected during the test along with an output file detailing the position of the motor can be analyzed regarding collagen realignment.

Participating in research this summer has increased my knowledge of the field of orthopaedic bioengineering, tendon injury and healing, and of the way research is conducted. This project has given me invaluable experience working with mechanical testing equipment, motors and cameras and acquiring proficiency in using Labview. Throughout the process of designing this setup, I gained a lot of insight into the meticulous detail required to build a custom apparatus used for testing. There were a lot of facets to this project that I had to consider, and the challenges were interesting to tackle. Overall, I enjoyed the project and the experience it has given me and am thankful to Dr. Soslowsky for his mentorship.