A New Challenger
MR27: Designing the Next Generation of TSC
Triton Solar Car is currently hard at work designing our next-generation vehicle, the Manta Ray 27 (MR27). Building on what we learned from the MR26, the MR27 introduces major changes across the vehicle while continuing to refine systems that performed well in our previous design. With a completely redesigned aerodynamic platform and a more optimized suspension system, our goal is to create the most competitive vehicle possible and become the first car in UC San Diego history to compete in the Formula Sun Grand Prix.
Aerodynamics
From an aerodynamic perspective, the MR27 is much more advanced than its predecessor. For this vehicle, we are moving away from the catamaran platform used by the MR26 to a skirted, lowered vehicle in an effort to simplify manufacturing and improve packaging. With this low and aggressive design, we are aiming for a low front area in order to achieve a highly competitive drag coefficient of around 0.1. Every inch of the MR27’s surface is currently being optimized and characterized in Ansys Fluent over a variety of speeds and conditions to give us a competitive edge. Because of the MR27’s unorthodox design, there is still a lot to discover, and the whole team is excited to continue developing this platform for years to come.
Suspension
The suspension, which connects the body of the car to the wheels, is an integral component to our success. Our goal is to keep traction on all wheels under various loading conditions while ensuring a comfortable ride for our driver, all while keeping the system light and minimizing energy loss. A major focus for the MR27 has been optimizing the kinematics of the suspension system. We are currently in the final steps of creating a parametric CAD model of the full suspension system, which acts as a template we can use to streamline the design of individual components. The CAD model has allowed us to increase focus on optimizing the kinematics of the suspension system by iterating on geometries such as kingpin inclination, scrub radius, roll center height, and camber while ensuring that all of the necessary components fit together.
Unlike the aerodynamics, which are undergoing a complete overhaul, the differences between the suspension in the MR26 and MR27 can mainly be seen in many small changes which cumulatively represent a large improvement. For example, the majority of the suspension system will be made from CNC-machined aluminum, which will allow our components to be lighter, more precise, and more accurate to our CAD models compared to the hand-welded components we used for the MR26.
The transition to mainly custom parts also presents a major advantage over off-the-shelf parts in the form of a higher degree of flexibility. Whereas the MR26 had a pre-built steering knuckle which forced us to work around the manufacturers dimensions, the MR27 has a fully custom steering knuckle, allowing us to include all of the features we want, and exclude any features we don’t need.
FEA analysis, which simulates the stresses in a part before we ever start fabrication, will be crucial to ensuring our custom built pieces can withstand the necessary loads while remaining as light as possible. Our next steps are to continue running motion analysis and simulations to refine the suspension geometry before moving into the detailed design and manufacturing of individual components.
Chassis
The MR27 features a complete chassis redesign centered around our new aeroshell and a significantly lower vehicle profile. By positioning the driver at a more aggressive lay-back angle, we have reduced the car’s overall height in order to minimize aerodynamic drag, improving energy efficiency. The MR27’s thin-wall chromoly steel chassis will use professionally notched tubing to achieve cleaner, more accurate joints. By increasing the precision of our manufacturing process, we hope to more closely translate our CAD designs into the finished chassis, improving dimensional accuracy and overall vehicle performance.
With the MR27, our focus is shifting from simply building a functional solar car to building a competitive one. With advances in our design and manufacturing processes, we are targeting an overall chassis weight of 60 kg and a vehicle top speed of approximately 45 mph. The experience gained from our previous vehicle combined with the talent and dedication of our team, gives us the foundation to make the MR27 a serious dark horse competitor at the Formula Sun Grand Prix.
Looking Ahead
For the MR27, there is not one single change that defines the new vehicle, but rather many improvements that build on what we learned from the MR26. A new aerodynamic platform, more refined suspension geometry, lighter components, and improved manufacturing techniques are all helping us push the design further. There is still plenty of work ahead as the MR27 moves from CAD and simulation toward fabrication and assembly, but our goal is clear: make the MR27 the first solar car in UC San Diego history to make it to competition.
