SAE SUPRA

SUPRA SAEINDIA is a premier national-level engineering competition organized by SAEINDIA, providing a platform for engineering students to design, build, and compete with formula-style race cars. The competition aims to foster innovation, technical skills, and teamwork among aspiring automotive engineers.

Competition Structure

SUPRA SAEINDIA spans five days and encompasses a series of static and dynamic events, culminating in a final endurance run and a valedictory function. The events are designed to evaluate various aspects of the student-designed vehicles:

Static Events: These include Cost Analysis, Business Presentation, and Engineering Design. The Engineering Design event assesses the creativity, technical soundness, and innovation in the vehicle's design.

Dynamic Events: These consist of Acceleration, Skid Pad, Autocross, and Endurance tests, evaluating the vehicle's performance, handling, and durability under real-world conditions.

Designing a Formula Student Spaceframe Chassis for SUPRA SAEINDIA: A Complete Breakdown

“Design isn’t just about making things look good — it’s about solving problems with precision and purpose.”
In this blog, I’m sharing the complete journey of designing a spaceframe chassis for our Formula-style race car as part of the SUPRA SAEINDIA student competition.

Step 1: Understanding the Challenge

Honestly, before jumping into CAD and all that, I spent time reading the SAE SUPRA Rulebook properly—and yaar, there’s a lot to follow! The rules are pretty strict when it comes to:

What tubing you can use (material, size, all fixed)
How strong the roll hoop has to be
Safety clearances for the driver
Where and how to mount the engine and suspension

This step really helped me get my head in the right space. I knew from the start that if the basics weren’t compliant, nothing else would matter.

Step 2: Concept Layout + Driver Packaging

I started with some rough hand sketches to figure out the overall chassis layout. It wasn’t perfect, but it helped me visualise:

The main and front roll hoops
Side impact zones
A cockpit that actually fits a human (we used the 95th percentile male to be safe!)
Engine bay clearance

We wanted to make sure the driver can sit comfortably while meeting all the safety rules. That balance is super important.

A this stage we selected the driver and made him site in the proper angles to get a brief how big the vehicle need to be and the width.

Step 3: CAD Modeling in SolidWorks

Once the concept was ready, I shifted to SolidWorks and started building the actual 3D model using the Weldments feature. Trust me, it makes life so much easier when you’re working with tubular frames.

Material: AISI 4130 Chrome Moly Steel
Primary tubes: 33.7 mm outer diameter, 4 mm thick
Bracing: Triangulated for strength and rigidity
Driver Template: Used to double-check clearances and ergonomics

💡 Pro tip: Use 3D sketches and custom weldment profiles to make sure your tube geometry is precise. Saved me a ton of time later.

Step 4: Rulebook Compliance Check

Once the model was coming together, I went back to the rulebook and cross-checked everything:

Clearance above the driver’s helmet
Bracing angles of the main roll hoop
Side impact zone geometry
Suspension + powertrain mounting points

Doing this early saved a lot of headache. Found a few small issues before they turned into big fabrication problems.

Step 5: Structural Planning

Even before running full FEA, I made sure to follow basic racecar design principles like:

Direct load paths from suspension points
No long, unsupported tubes
Proper bracing of every major node

Sometimes, it’s not just about simulation — good engineering intuition matters too.

Step 6: Fabrication-Ready Drawings

After finalizing the CAD model, I prepared everything needed for actual fabrication:

Tube cut lists (lengths + bend angles)
2D drawings for each sub-assembly
Fixture plans to maintain accuracy while welding
Welding sequence guidelines

This made it super smooth for the team during the actual build. No last-minute guesswork.

Revisions & Iterations

Of course, it wasn’t a one-shot design. After some feedback from teammates and mentors, I had to tweak a few things:

Widened the cockpit opening for easier entry/exit
Adjusted suspension pickup points
Moved the firewall slightly
Strengthened some mounting points

Every small revision made the design stronger and more race-ready.

Final Result

By the end of it, we had a chassis that was:

Lightweight, spaceframe-type
High in torsional stiffness
Fully compliant with SAE rules
Easy to fabricate using MIG/TIG welding

What I Learned

This project wasn’t just about learning CAD. It taught me a lot more:

Real-world problem-solving under tight constraints
Importance of team communication
How to balance safety + performance
And most of all, how to design like an actual motorsport engineer

To be honest, this whole thing made me feel like I was building something real, not just doing a college assignment.

Chassis Gallery

Let’s Connect

If you’re a student, SAE team member, or just passionate about motorsport design, I’d love to connect!

👉 www.linkedin.com/in/ananthu-rapoyil
👉 r.ananthu074@gmail.com
👉 Download full chassis CAD Model: https://grabcad.com/library/supra-frame-2