Paper Title
Design of Expanding Pulley Mechanism for a Continuously Variable Transmission in E-Bike

Abstract
The concurrent chain drive systems that are being employed in the current bicycle transmission systems have thus shown few areas which need efficiency improvement. In accordance with that, newer belt drive transmission systems are now taking their place with better customer satisfaction thereby improving the transmission efficiency and giving an overall comfortable driving experience. The modern day belt drive transmission systems employ ductile stress resistant belts which have lived up to the efficiency parameters and thus are now being looked at as potential transmission systems. This system works on the principle of expanding pulley mechanism. It employs the use of motor which rotates the scroll which in turn changes the effective radius of the pulley and gives infinite reduction ratios. The motor takes inputs from the torque sensor, motor rpm, and gyroscope which are installed on the e-bike hence relieving the user from the hassles of shifting gears. The tension of the belt is maintained by an idler pulley which uses a torsional spring. Keywords - Transmission System, Belt Drive.