Spartan V8: Frame Design

www.SpartanV8.com

Welcome to my latest project, the Spartan V8 prototype roadster.

Take a look around, and feel free to leave a comment!

What is it?
A: The Spartan V8 is a type of high performance car called an "exoskeleton" car, exoskeleton referring to the framework of the car which is both visible and aesthetic by design. It is being designed entirely from scratch, by me alone (constructed and tested entirely in SolidWorks). I'm about a year into the design; from initial idea, to working concept, to full 3d virtual model. Once I have the remainder of the crucial components (engine, transmission, suspension, etc) modeled accurately in 3D, I'll be able to finalize the design and begin construction.

What would it be like to drive?
A: Something like this.
The metallic click of a switch engages the ignition and fuel pump with a hum. You engage the clutch and push the starter button.. the V8 engine thrashes and bursts to life with a snarl, sending shivers through the frame, and straight up your spine. The shifter in your right hand snicks into gear, and you ease out the clutch and apply the throttle.. by the time you fully release the clutch, its already time to shift into second. As you shift to 3rd, 4th, 5th, and 6th, the sheer acceleration nails you to your seat, the exhaust roars to either side of you, the intake growls in front of you, the big 305 series tires shriek in protest as they claw at the pavement, the wind whips past your head and body, and you are catapulted to speed more rapidly than you thought possible.
A stab at the brakes invites the race compound pads to bite into four oversized vented rotors, rapidly bringing you to a screeching halt.. brutally throwing you forward against the belts of your 5 point harness, threatening to eject you from the cockpit as you slow back to a stop. Your pulse is racing, your breathing is quickened, and the back of your neck is tingling. Savage and raw, the Spartan V8 isn't just quick. It is downright terrifying.

More akin to riding something wild, overpowered, and foaming at the mouth than just driving a car. It roars, it screams, it snarls. It thrums with power lurking just under its thin skin, daring you to mash that accelerator to the floor, and chase down something exotic..

Why design and build your own car?
A: Why not? It will be fun to design, build, and drive. It will be a learning experience like no other. Also, because of it's tremendous power to weight ratio, the Spartan will be a veritable supercar - more than able to hold its own on the road or racetrack against other street cars costing hundreds of thousands of dollars.

Check back whenever you like, as I'll be adding updates frequently.

Saturday, October 17, 2009

Frame Design

There is a lot that goes into the design of a chassis frame. One advantage of using SolidWorks to design my frame in is that it has a built in finite element analysis (FEA) program. FEA allows one to apply a load on a part, assembly, or frame, and see how it reacts to that force. In this case, I'm applying two forces, equal and opposite, to the front end of the frame. These forces are actually applied to the points on the frame where the weight of the vehicle pushes on it, mimicking cornering loads, acceleration loads, or other scenarios.

Since the frame design has been modified many times since I did the original FEA work on the preliminary frame models, now it is time to go back through and make sure I haven't introduced any weak points. It is likely that the frame design will still change a bit more, as the engine and transmission dimensions and mounting points are finalized.

This screenshot shows a stress plot of the frame while under load. Red areas are highly stressed, blue areas are not. From this shot, it is apparent that there are still some stress concentrations to be designed out, although to be fair, the front engine bay area is missing a few key tubes.