A semester long project for my Machine Element Design class, designing the shaft, gears, and bearings for a lawn mower gear reducer. n part one of the project, we did a simple static force analysis on the gear box given the input conditions (motor power and speed, desired output power, gear ratios and bearing configuration). After that, we used Distortion Energy Theory to analyze the critical stress element of each of the three shafts to determine minimum shaft diameters given a predetermined material. Then in the next part we bear-tooth bending and surface fatigue analysis to determine the minimum width of each of the gears. Finally, we designed the shafts complete with different diameters at each force element (to minimize weight), shoulders (including calculating stress concentration factors and fatigue analysis), and selecting bearings.

View the final report here