Welcome to the “Creating a Belly Racer with SOLIDWORKS” blog series. If you need to catch up, you can start with the first one here.
As I indicated in the second blog in this series, we’ll start to look at the Belly Racer chassis design in more detail in this Blog. Keeping with the original design intent Paul Cameron defined at the beginning of this project, the Belly Racer chassis will be based on an airplane airframe. An airframe is defined as the mechanical structure of an aircraft. An airframe is typically made out of aluminum because access weight must be kept to a minimum.
We’ll follow the same rule with the Belly Racer and minimize the weight and use aluminum T-6061 for the majority of the chassis design. Steel will be used for critical components such as the roll bar and surrounding driver protection which will be integrated into the chassis design. The design of the Belly Racer chassis will be comprised of Bulkheads, Stringers, Longeron and the Skin. Here’s a good image showing what these components look like.
When I started the Belly Racer Project Paul Cameron supplied me with his concept models shown here.
I used Paul’s models as reference for the chassis design. The finished design looks similar to these models. A lot of additional features were added to the components to make assembling and welding the chassis easier by using self fixturing components. Here are images of the SOLIDWORKS assembly model of the chassis.
The design is fairly simple as you can see. The intent is to manufacture the Belly Racer as a kit so someone can build and race it. Each component will be laser or water jet cut out of T-6061 Aluminum.
Assembly and welding will need careful planning because of the way each piece fits together. Here’s the front suspension main bulkheads and stringers, which shows the tabs and slots used for the self fixturing in this exploded view.
Looking at the rear end of the chassis we see where the “T”-shaped stringers attach to the differential housing. The horizontal component of the “T” is bent slightly so it will conform to the curved shape of the body skin and the vertical component will fit into the slots in the bulkheads. The slots will help with assembly and welding without the need to elaborate fixturing.
Here’s an overall look at the chassis. There’s one component not shown and that’s the roll bar/driver protection cage. I’ll show that in the next blog.
To get an idea of the strength of the chassis, we ran some simulation studies on the chassis with the body skin in place. A weight of 200 lbs. was placed in the driver’s seat to mimic a driver. A linear static simulation study was performed using the 3DEXPERIENCE Simulation Structural Mechanics Engineer. Here are the results from one of the static studies. The maximum displacement is 0.3mm, which is mostly in the seat.
We’ll be doing other types of simulation studies to check the structural integrity of the chassis in both static and dynamic situations.
Until the next blog cheers!