A Study of Ackerman Steering and Its Applicability to SAE Mini Baja

Ackerman steering is one of the most common ideal geometries for steering systems.Based on the concept of each wheel turning on a radius around a point along the line of the rear axle, Ackerman steering minimizes tire scrubbing, thereby increasing grip, improving turning capabilities, and decreasing wear on the system as a whole.Ackerman steering is particularly applicable for low-speed, off-road vehicles whose tires dig into the ground more.SAE Baja is a competition for collegiate vehicular testing, in which constructed vehicles undergo the various rigors of off-road racing.Geneva College senior engineering students work on a Baja kart every year, with the goal of competing each spring.This 2023-2024 school year, the Baja team inherited a Baja kart that had been damaged during competition the previous year.The steering system was part of the damaged equipment and had been subsequently mended with an old, retired steering rack.Due to this repair, the resulting steering geometry differed from ideal Ackerman by a significant degree.The goal in this paper is to obtain a more ideal steering geometry.To that extent, the current geometry was first analyzed using the 2D physics modeling program Working Model 2D to understand and analyze the faults in the geometry.Following that, a system of three equations was used to obtain the dimensions necessary for constructing ideal Ackerman steering geometry.With the proper dimensions, as well as taking into account current geometrical constraints including wheelbase, track width, and tie rod geometry necessary for bump steer elimination, a new model was built in Working Model 2D and was confirmed to agree with ideal Ackerman steering.Following 2D analysis, both the old and the new steering systems were modeled in 3D space using Autodesk Inventor and then printed with an Ender 3 S1 Pro 3D printer.The 3D models were then tested, ensuring ideal Ackerman behavior continued on the new system as expected, even with a physical system.Finally, the new steering geometry was recommended for use by current and future teams, with the goal of promoting ideal steering geometry for a better handling kart.