Milestone 5: Conical CVT Testing

Overview

The variable speed dropbox (Figure 2) was tested on the dynamometer on November 6th, 2025, to test if the conical CVT design (Figure 1) worked as intended. During testing, the design proved to be partly successful. Results from the testing show that when the belt was placed in the middle setting (1:1 gear ratio), shown in Figure 3, the speeds of the input and output shafts were both 2300 revolutions per minute. For the 1:2 gear ratio setting, the input and output shaft speeds were 2300 and 1450 revolutions per minute, respectively. For the third setting (2:1 ratio), the top and bottom shaft speeds were 2300 and 3800 revolutions per minute, respectively. During testing, the V-belt exhibited signs of wear, particularly when positioned at the end of the cones. This is likely due to the belt rubbing the extrusion of the cones made to keep the belt from falling off. We also decided to test the V-belt underload to see if this was a valuable option for our belt drive system. However, due to the geometry of the belt, slippage occurred under minimum load, showing that more testing with a different belt should be completed.  The V-belt was an alternative to the desired flat belt that had to be used due to shipping delays. In the future, we plan to additionally test the flat belt to compare its efficiency with the V-belt.