As a member of MIT's Solar Electric Vehicle team, I had the opportunity to lead the design and manufacturing of our car's steering system. As the lead for the steering system, it was my responsibility to ensure that the system was robust, effective, and safe. Throughout the system's development, it was important to think of the ways in which it interacted with other systems on the car such as the front suspension. I designed and analyzed various parts of the steering system in Solidworks. I made prototypes of some parts, such as the pinion mount. These prototypes were helpful to verify the geometry of the system before we manufactured the whole system. By leading this project, I learned a lot more about engineering systems and how to apply what I learn in the classroom to real problems.
Steering System Overview
Gemini’s steering system uses an Ackerman design, allowing us to precisely control the angles of both front wheels. The steering system starts with the input assembly, which contains the steering wheel, steering wheel shaft, and supporting components. The steering wheel shaft connects to the steering wheel with a roll pin through the steering wheel shaft and steering slug. The splined side of the slug is attached to a quick release mechanism on the steering wheel. A U-joint is bolted through the steering wheel shaft and the intermediate shaft. The intermediate shaft allows the motion of the steering wheel to transmit to the rack and pinion.
Another bolted U-joint connects the intermediate shaft to the pinion. As the pinion turns, it slides along the rack which in turn moves the linear slider. Steel retention rings serve as steering stops and are mounted on each side of the rack and pinion to prevent over extension of the system. The tie rods are attached to the slider. One tie rod goes to each front wheel, so that as the tie rods move with the linear slider, they can pull or push the wheel into the desired orientation. On each side, a welded steering arm is attached to the tie rod front side rod end and bolted to the front suspension’s upright.
