RC Car Drivetrain and Steering

To test engineering discipline, two students in the Mechanical Engineering Technology department at Central Washington University will be tasked with interpreting ROAR (Remotely Operated Auto Racers) restrictions and RC car design guidelines to create an RC car capable of competing in RC Baja race environments. The design of the drivetrain mimicked that of an actual automobile. Through an understanding of torque, inertia and gear design, an open differential was designed. The final design consisted of a 2:1 and 4:1 spur gear pair with an open differential consisting of three 1:1 miter gears. The primary engineering methods used to create the assembly were turning, 3D printing and drilling. Gears and supports were 3D printed due to irregular shapes, while the axles were created by turning aluminum rounds to a desired diameter. Certain parts were purchased based on their difficulty of manufacture, such as universal joints, wheels and all electronics. Due to the project being divided between two students, only the steering and drivetrain will be discussed here. For the steering, the system consisted of a servo mounted to the front of the car, with two tie rods connecting to rotating feet. This design will successfully meet the requirements of turning the wheels 60 degrees in each direction. As for the drivetrain, this design will fulfil the requirements of reaching a maximum speed of at least 25mph while gear teeth remain intact