Discipline: Technology and Engineering
Subcategory: Electrical Engineering
Room: Exhibit Hall
Ali Ahmed-Nassir Ibrahim - Ohio State University
Co-Author(s): Asimina Kiourti, Ohio State University, OH
Countless advances across various fields are being made with the development of wearable technologies. Wearable kinematic monitors in particular are being developed with applications in healthcare, sports medicine, virtual reality, and more. The current “gold-standard” method of measuring human kinematics is motion capture with the use of reflective tapes tracked by video cameras. This method is accurate but is limited to a contrived laboratory environment. Other methods that overcome this limitation exist, but they suffer from other limitations and restrictions of their own. For example, Inertial Measurement Units have been used to track kinematics, but the device suffers from integration drift. Physically bending devices used to measure knee flexion angle tend to obstruct the natural motion of the knee. To address these drawbacks in the state-of-the-art, we have recently reported new classes of sensors that can be embroidered into garments to monitor joint kinematics in any location (V. Mishra and A. Kiourti, “Wearable Electrically Small Loop Antennas for Monitoring Joint Flexion and Rotation,” IEEE Transactions on Antennas and Propagation, vol. 68, no. 1, pp. 134-141, Jan. 2020). By embedding electrically small transmitter (Tx) and receiver (Rx) resonant loops right above and below the joint in question (the knee), the sensor can detect the relative angle between the two loops via Faraday’s Law of Induction, thus detecting the joint’s bend angle.In this work, we present three new designs of sensors to test the hypothesis that they will each improve upon a previous design’s measurement resolution at low angles of flexion. The number of resonant loops, the geometry of the loops, and the position of the loops on the model leg were independently varied between each new design and the previous design. The designs were created in CST Microwave Studio and were tested with a parameter sweep simulation of the model leg’s flexion angle as the sensors were excited by a 34MHz electric signal. Simulation results for each design were compared with results from previous literature to compare low-angle measurement resolution. Results show that measurement resolution did not improve in any of the three new designs, however one design showed simulation errors that made the results inconclusive. We conclude that the inconclusive design warrants future re-testing and possible physical-model experimentation, while the other designs do not improve measurement resolution and do not warrant future testing.References: Creaby MW, Hunt MA, Hinman RS, Bennell KL. Sagittal plane joint loading is related to knee flexion in osteoarthritic gait. Clin Biomech (Bristol, Avon). 2013 Oct;28(8):916-20. doi: 10.1016/j.clinbiomech.2013.07.013. Epub 2013 Jul 26. PMID: 23938182.P. Giraruchataporn, K. Ekkachai, P. Peuchpen, S. Kijpaiboonwat, W. Kongprawechnon and S. Hasegawa, “Smart Shoe For Predicting Knee Abduction Moment,” 2022 13th Asian Control Conference (ASCC), 2022, pp. 162-166, doi: 10.23919/ASCC56756.2022.9828314.V. Mishra and A. Kiourti, “Wearable Electrically Small Loop Antennas for Monitoring Joint Flexion and Rotation,” in IEEE Transactions on Antennas and Propagation, vol. 68, no. 1, pp. 134-141, Jan. 2020, doi: 10.1109/TAP.2019.2935147.
Funder Acknowledgement(s): The research was funded by an NSF grant under Award No. 20426644. Funding was also provided by an NSF/EFRI REM grant under Award No. 2207091.
Faculty Advisor: Asimina Kiourti, firstname.lastname@example.org
Role: I created and simulated the three sensor designs in CST Microwave Studio, and interpreted the results. I did this under the mentorship of Dr. Asimina Kiourti.