SteadyStride - The Tremor Resistant Cane
September 2023 - May 2024 • Cornell University • Cornell DEBUT Project Team • Device Design, Dynamic Modeling, and Prototyping
As a part of Cornell DEBUT, I have been a part of designing a cane with a built-in tuned-mass damper intended to effectively dampen hand tremors. The prototype comprises of two main characteristics: a spring-based, two-degree freedom damper, in addition to a specially 3D-printed base for increased surface contact during gait. The project is a part of the teams' two-year design cycle, and I have joined as an analyst in mechanical design, modeling, and experimentation. The idea is a shared effort, however, all the following media is either solely produced or led by myself on DEBUT.
2024 Medtronic BMES Design Competition Finalist
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2024 Medtronic BMES Design Competition Finalist 〰️
Mathematical Modeling (MATLAB)
In order to confirm the efficacy of the design idea, I began the development of a modeling program that a) plotted the position of the whole cane with preset mass and spring constants and b) plotted the average residual of each motion in a 3D plotter as mass and spring constants are changed. Although our general grasp of the tuned-mass damper system was understood, I thought it was beneficial to specifically delve into the mathematical aspects that lent towards the damping effect anticipated for a patient suffering intense hand tremors. The MATLAB script solves the system of four ordinary differential equations given the preset mass and spring variables, and stores the values of position in a mutable array, and the average residual in another. MATLAB files are accessible through the buttons below:
Fusion360 3D Design
Following confirmation through the mathematical modeling, the next steps involved creating more specific designs for the components. Referencing an ideal spring and mass combination from the previous model in addition to some prior concept sketches, I designed the current iteration of the integrated tuned-mass damper with the tremor-resistant cane. Additionally, I provided a conceptual design for the stabilizing base with the intent of implementing flexible TPU as the main material. All components shown are comprised of parts referenced from MacMaster and are fully jointed to simulate the real-life assembly of the device.
Manufacturing
Currently, the cane is in the manufacturing stage, and although still early on, some initial parts have been sent out for 3D-printing. With my experience in rapid prototyping, I have been consulting on the qualities and characteristics of each specific part. I personally 3D-printed the initial concept for the stabilizing TPU base to test the proper infill required for a mixture of rigidity and flexibility in the design for proper use. Additionally, I interfaced the part with the stem of a typical aluminum cane and confirmed the strength of the design. From here, I will continue to focus on assembling the prototype for the tuned-mass damped, in addition to conducting some rudimentary testing before integration into the cane.
Patient Trials (IRB-Approved)
After filling for IRB-approval at the start of 2024, our team began developing the final prototype for patient use and design some experimental testing equipment. The final prototype utilized in patient testing is shown in the video below, and usage is demonstrated by me. With a functioning design, I created an accelerometer-based sensor connected to a TPU arm-strap to record relative changers in hand tremors. With data acquired from testing at SUNY Cortland’s Kinesiology Lab, I filtered and analyzed the data in MATLAB, determine between a 12-15% decrease in relative hand tremor amplitude for 3 out of 4 of the patients in the direction of tremor propagation.
Poster Session
Here is a poster I was a major contributor for describing the progress of the project prior to testing:
