Custom Rack Designer
As a Mechanical Advisor and former steering lead, I designed the first ever custom SAE steering rack and pinion for the University of Toronto Formula SAE Racing Team. This endeavor proved to be one of the most demanding, beginning with extensive research into existing off-the-shelf (OTS) racks. I dissected several models in our shop to gain a deeper understanding of their components selection. From there, I progressed to hand calculations to determine the required rack travel for optimal performance.
Once I established the rack travel specifications from Adams MSC, I shifted my focus to gear calculations, which involved determining the necessary number of teeth and gear ratios for our design. These parameters were then inputted into a gear analysis software KISSsoft. In parallel, I conducted a thorough force analysis to select appropriate bearings and bushings that would ensure reliability and performance under load. I also narrowed down a few suitable steering angle sensor and planned its mounting, ensuring that all components would integrate seamlessly within the overall design.
During the CAD stage, I modelled the rack, pinion, housing, and various mounting elements. This phase was followed by finite element analysis in Ansys to evaluate the structural integrity and performance of the design (including static, dynamic and transient behavior of the system). The final step involved weight optimization to enhance the efficiency of our steering system. Importantly, the steering rack is designed to be adaptable, featuring adjustable rack travel, provisions for steering angle sensor (SAS) or brushless DC motor (BLDC) mounting for autonomous systems, and backlash adjustability to meet our evolving requirements.
The assembly was then 3D printed to test the gear mesh and tolerances of the components.
