BYU Applied Biomechanics Engineering Laboratory (BABEL), under the direction of Dr. Anton Bowden, researches several topics on the human lumbar spine, including spinal motion, intervertebral discs and spinal ligaments, with the goal of identifying causes of lower back pain. Ligaments are important to stability and motion and characterizing their behavior will increase our understanding of the complicated biomechanics of the spine. Most labs use a tensile testing method that is difficult and wasteful as gripping the slippery tissue presents a variety of problems and large samples are needed. The BABEL has developed a ligament tester that is the first of its kind and allows them to study the anisotropic property of ligaments.

BABEL recruited BYU capstone team 9 to learn the details of the design requirements and produce the next generation of testers that will allow for the characterization of material properties of spinal ligaments. The main design requirement was to get the maximum anisotropic response of a ligament sample. The team considered how the material response changes with the shape of the specimen, what the grips are, and how the loads are applied. They developed a semi-automated station with a motor to move their tester at a user defined speed and displacement, while collecting force-displacement data and camera images.