Document Type

Undergraduate Project

Date of Degree Completion

Fall 2022

Degree Name

Bachelor of Science


Mechanical Engineering Technology

Committee Chair

Charles Pringle

Second Committee Member

John Choi


This project is sponsored by JCATI (Joint Center for Aerospace Technology Innovation) to research and manufacture a machine to recycle strips of carbon fiber from retired aircraft wings. The drive train powering the crushing wheels was not delivering enough power into the crushing wheels to completely delaminate the strips of carbon fiber. Another issue experienced was the spur gears transferring power between crushing shafts failed.

This issue was first approached by analyzing the gear reduction ratio powering the crushing wheels. Then the next analysis was performed to find the amount of torque required to delaminate the carbon fiber. The minimum delamination of the carbon fiber was calculated to be 2114 lb-ft. Once this was complete it was realized the gear reduction ratio needed to be increased in order to output more torque into the crushing wheels. The gear reduction ratio was accommodated by increasing the gear reduction ratio from 2000 lb-ft to 2500 lb-ft. The failing spur gears were re-analyzed using a spur gear analysis. The previous set of spur gears were analyzed with a diametral pitch of 8 with 64 teeth on the gear. The new set of gears were redesigned with a diametral pitch of 5 with 40 teeth on the gear.

The increase of the gear reduction ratio allows for the crushing wheels to achieve 2500 lb-ft of torque, achieving complete delamination of the carbon fiber strips. The decrease of diametral pitch from 8 to 5 allows the spur gears transfer power without part failure.

Keywords: drive train, delaminate, crushing wheel, gear reduction


SOURCE 2022 Presentation: