Document Type


Date of Degree Completion

Spring 2019


Mechanical Engineering Technology

Committee Chair

Dr. Craig Johnson

Second Committee Member

Dr. John Choi

Third Committee Member

Professor Charles Pringle


A device is needed that can power the back wheels of R/C car and allow it to drive smoothly. This drivetrain also has to transmit power to the axles in an acceptable height range to comply with the frame and suspension. The project was supported by a team member who designed the frame and suspension. The design of this project consists of two sub-assemblies that make up the drive train assembly. The transmission assembly uses gears to convert the rotational speed from the motor to the drive shaft. The gearbox assembly also uses gears and converts the rotational speed from the drive shaft to the output shaft which powers the axles. To transmit the power from the electric motor to the wheels the two gear pairs and two shafts are needed. The spur pinion is attached to the motor and mates with the spur gear to drive the drive shaft. The driven shaft also has two u-joints at the end of it to make up the height difference between the drive shaft and driven shaft. The gear box houses the bevel pinion and gear which mate to rotate the output shaft to power the vehicle. This device was tested to meet the requirements of the project. The device transmitted the rotational motion of the motor to the rear wheels of the vehicle, had an acceptable total gear ratio of 12.5:1, met the weight requirement of less than 1 pound, and costed less than $200.