Authors: Eli F Smith, Christopher Dillon, Matthew S Allen
Mentors: Matt Allen
Insitution: Brigham Young University
Background: Shear wave tensiometry offers a method to measure in vivo tendon tension, crucial for inferring applied loads on tendons. However, existing equipment for this purpose is costly and lacks mobility, limiting the ability to study a larger cohort of subjects engaged in various physical activities.
Goal: This research aimed to assess the viability of utilizing low-cost digital accelerometers in conjunction with an Arduino-based microcontroller for shear wave tensiometry.
Approach: This work employs surface-mounted accelerometers on a custom flexible printed circuit board (PCB), so that even spacing can be maintained between the accelerometers without interfering in data collection. To test the system and verify its ability to acquire measurements at a high enough rate, the PCB was connected to a shaker driven with a known sinusoidal signal. The flexible PCB was held in place on the Achilles tendon using athletic tape with a tapper placed on the tendon to send a shear wave through the tendon.
Results: The results obtained to date compare the accuracy of the proposes system relative to the current system, which uses instrument grade accelerometers. Results obtained to date on the tendon reveal the degree to which the PCB interferes with the measurements, and suggest possible modifications to improve future designs.
Conclusion: To attain valid shear wave tensiometry data, further iterations of the flexible PCB design are needed. Moreover, employing more powerful microcontrollers capable of accommodating the requisite sample rates is necessary for an improved system.