I’ve always thought an Open source car design using Open source software would be amazing.
With enough people and diverse enough interests you could really build something complicated and unique. The project could be broken up and Teams could be established based on different areas of the vehicle where different expertise is required. A group could develop an ECU and the Electrical system, while others focus on the powerplant integration and design, while others do Bodywork and interior, Etc.
Use of open source CAD, Rendering, Simulation software would keep the project approachable by the most people which should increase the quality of outcome.
That said the key to success would be like any project, Defined goals and solid project plan. From experience this is not easy even when you have the “goal” set out before you (FSAE).
You have to get sufficient numbers of people to agree on a path or purpose for the vehicle to move forward otherwise you wind up with multiple unfinished designs. My design committee on the MG and LMP360 has been a total of 1 person and even then I can’t always get them to agree on a path forward.
That said here’s my thoughts on what would make a successful and useful project for “GRM open source”.
1. Modularity: Identify Key components and interactions in the vehicle that can be adjusted for different uses and applications. Think a Open Source Vehicle Architecture instead of a single open source vehicle. Think of things like Front Suspension as a modular unit that can be adjusted for different applications. Develop a Spring / suspension design concept that can be adjusted slightly for things. Make 1 “Passenger Cell” that you stretch width wise for Front Engine vs Mid Engine. DP cars does a good job with this and is worth a read for anyone considering this. They have a “D47” project that is basically a modular car concept. Most Manufactures are moving this way also. VW makes like 1 car just of different sizes.
2. Have a Custom and off the shelf solution for most problems. Design seats but also make sure some type of Commercially available seat fits. Make the perfect fuel cell custom but also ensure a smaller off the shelf design works. This gives flexibility to the final builder of the car and ensures that you have room if you make mistakes.
3. Stick to the Plan. Keep the end goal in mind from the beginning and don’t skip gates. Project planning should have a series of Stages and Gates. Stages are usually something like Problem Identification -> Concept Development -> Detailed Design -> Prototype -> Validation. They are broken down further, and some steps get repeated like Design/Prototype. At each Arrow you come together and validate that the goals of each Stage are done BEFORE you move on to the next Step. You don’t open the GATE until the entire herd is ready to move to the next field.
4. Use Production vehicle components when it makes sense to do so. Things like Uprights, Brakes, Steering Racks are readily available in numerous designs with 1000s of hours of testing and use to mess with making your own. Unless the chosen application has VASTLY different design requirements then production it only make sense to use them. There is a place for Fabricated uprights is your car is trying to be 500lbs or is going to be jumping 20’ in the air but for most vehicles an off the shelf solution is probably best.
5. Bake serviceability and longevity into the plan. Understand the stresses on components and overbuild the Safety Factor on some to create fuses in the design so complicated parts don’t have to be rebuilt over and over again. Make it so getting the Engine out doesn’t require the equivalent of Automotive Yoga to get the chassis in JUST the right angle. Don’t optimize the design around the use of 14” wheels that won’t be available in 5 years. Don’t use obscure car parts that are no longer in production.
So what would I build?
For Track? a cheap LMP car obviously.. No Seriously.
Racing and Trackdays are getting Ludacris. Cars are getting heavy which takes big HP to go fast, which takes BIG brakes to stop, which takes big tires to keep on the track. Big on racecars cost money. But at the opposite end Small and Light costs big money too. Carbon Fiber has become the Answer to every problem and costs to be “light” are out of hand. Cars like the NP01 and Rush SR exist but they aren’t Exactly cheap. We need a Modern version of What Formula Vee was. And I know F500 exists and that’s great but I want an enclosed car.
An enclosed steel tubular frame car should be great for the DIY set. Building something a little less 10/10ths from a design standpoint may add a few hundred lbs to something like a Radical but will still be nearly 1000lbs less then your typical Miata.
1500lbs and ~200hp is FUN on a track and can keep up with some serious hardware while having low operating costs. I think a car design that ends up looking LMPish with relatively easy to build bodywork using a FWD automotive drivetrain (an alternate design for a Bike Engine could easily be made) could be developed that should cost around $7500 for your typical builder to build. Used parts could drag the price down to as low as $3000 (Steel got expensive since I built the LMP360) and use of big $$ parts could probably still be done for $15K.
But that said I’d be in to help with whatever the Hive mind thought would be fun.