Midnight Sun is a University of Waterloo, Ontario, student team that designs, builds and races solar-powered cars. We strive to bring awareness and interest to renewable energy technologies and their possible integration with vehicles, while giving students from all disciplines an opportunity to develop practical skills that can’t be taught in the classroom. We rely extensively on ANSYS structural simulation solutions to lightweight our race cars while ensuring they retain the necessary strength for performance and safety.
Midnight Sun 12 (MSXII) is our twelfth solar car to date, and our second cruiser class car. Cruiser style vehicles focus on a more practical, user-oriented design than the typical spaceship-like “challenger” class vehicles. Cruiser class vehicles must be lightweight to remain efficient and competitive, while still being structurally sound to protect the two occupants of the car.
At the core of any car, solar or not, is a metal chassis that acts as the skeleton for the rest of the car’s components. ANSYS Mechanical was employed extensively to optimize and iterate the design of our steel space-frame chassis, which netted a weight reduction of 25 percent from initial concept to final design.
Simulation of a chassis composed of 100-plus members usually requires extensive computing power and long solve times, but, thanks to the beam element and mesh refinement tools built into ANSYS Mechanical, the solution was quick and easy. Beam elements enabled chassis iterations to be meshed and solved in several minutes, while mesh refinement tools allowed our team to remove unrealistic stress concentrations to extract realistic results from our simulations.
ANSYS solutions helped us to reduce the chassis mass from 75 kg down to 55 kg, all while maintaining a required safety factor of 2.5.
ANSYS tools also allowed us to analyze the strength of our dynamic vehicle components, such as suspension and steering, and identify areas for lightweighting to keep MSXII competitive. The ability to easily simulate assemblies containing multiple bodies allowed us to achieve much more accurate results.
The powerful mesh refinement tools in ANSYS solutions allowed us to simplify the simulations by making the mesh finer in areas of interest to reduce solve/compute times. ANSYS solutions allowed us to effectively identify any high-stress areas and regions with low safety factors in our design before manufacturing, so we could eliminate these concerns early in the process.
Midnight Sun is eagerly looking forward to competing in the American Solar Challenge in the summer of 2018. While most of our main dynamic components and our chassis have already been manufactured, ANSYS Mechanical will still be an invaluable tool in our toolbox as we finalize all aspects of our vehicle to balance weight and safety. To learn more about Midnight Sun, visit our website.