Limitations and design considerations for a continuously variable transmission utilizing the conservation of angular momentum and gyroscopic precession



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Continuously variable transmissions(CVT) are generally superior to their multistage alternatives in the automotive industry. Wind turbines are traditionally designed around cheaper single stage gearboxes, but have bearing problems. CVTs could potentially increase the productive capacity of new wind turbines while alleviating the stresses on some turbine components. Current CVT designs cannot be scaled to the largest wind turbine sizes and are too inefficient to be of use in an energy generation capacity. Gyroscopic CVTs could potentially remove the friction and tension constraints of current CVT designs, but a century of design progress has not yet yielded a functional design. A new design restriction, the McGyro Principle, allows investigators to quickly analyze a proposed gyroscopic CVT and determine if that transmission will produce oscillatory or continuous rotation. A literature review search of current gyroscopic CVT designs finds that all prior attempts fail the McGyro Principle or defy another physical law. A new gyroscopic CVT design following the McGyro Principle is proposed as a new iteration in gyroscopic CVT design. A corollary to the McGyro principle is also proposed and implemented within the new design. A dynamic simulation of the design using Kane's Equations is given and used to choose physical constants in the construction of a physical prototype. The physical prototype is shown to drive a load at multiple speeds and it is demonstrated that the dynamic simulation comports with the physical model. Dynamic analysis of the mechanism to test for stability in variety of perturbed operating conditions was done by bifurcation analysis and motion attractor stability plotting. Further investigation into higher harmonics revealed additional types of motion, but none practical to the purpose of this work. A gyroscopic frequency locking phenomenon is used to suggest future avenues of research.



Continuously variable transmission, Gyroscopic transmission, Angular momentum, Gyroscopic precession, Autation