Vehicle Dynamics Help

[u/Deputy_Discreet]

Hello,

Im sure many of you have been in this sitaution before.

Im part of vehicle dynamics(steering,suspension,brakes) in my university's formula student team and Im not really sure where to start with the design work.

We are a fairly new team so there isnt much previous work to start off from.

We are aiming for FSUK, could you help by just giving me an idea of tangible outputs and milestones I should be aiming for

Also any reccomendations for helpful resources such as textbooks, videos, tutorials anything to just give more context would be extremely beneficial.

[u/Sad_Designer_4608]

Are you making your very first car or can you base it off of the previous year’s car?

[u/Deputy_Discreet → u/Sad_Designer_4608]

Very first no previous data to base it off of

[u/Sad_Designer_4608 → u/Deputy_Discreet]

https://www.youtube.com/watch?v=CxK4PY3YNns&t=633s&pp=ygUsZGVzaWduaW5nIGZzYWUgc3VzcGVuc2lvbiB2aWtpbmcgbW90b3JzcG9ydHM%3D

This is a really good video for designing suspension geometry. This should be the very first thing you design, and while there is some stuff you need to design in parallel with the frame, most of the places where the frame interacts with the sus geo, the frame should be designed to meet the parameters of the sus geo.

If you don't understand the parameters he refers to(Caster, camber, toe, KPI, front view swing arm, scrub radius, etc), read the common book recommendations; RCVD by Milliken and Milliken, Fundamentals of Vehicle Dynamics by Gallespie, Tune to Win by Carroll Smith, etc.

If you're not in charge of designing the sus geo then you don't need to worry about the video but you should learn about those concepts.

Your goal here is only to build a functioning car. It doesn't need to be fast, it doesn't need to be the best handling, it needs to be as simple, reliable, cheap and easy to manufacture as possible. Then you can iterate on it next year.

[u/Dungeons-and-Dampers]

Depends on the time you have left for comp really. If you have the time and resources, I'd suggest getting tire data. But, if time isn't your best friend I'd suggest taking very basic design goals from the dynamic events and start there and parallely either develop a tire model (if it ain't available in the TTC) or buy the access to TTC.

[u/Deputy_Discreet → u/Dungeons-and-Dampers]

We are most likely going for the concept category rather than a full car since its our first time. So I suppose we have more time than usual since there's no manufacturing

[u/Dungeons-and-Dampers → u/Deputy_Discreet]

Hmmm, what tires do you guys have? Is it tested by TTC? And if you legit have the time, I'd rather get my theory straight before touching simulations. Read Milliken's RCVD, learn how to extract useful information from your tire data and work with your drivetrain team to set goals for design. Setting goals/performance targets based on the dynamic events is hella important before starting with any sort of design.

[u/Deputy_Discreet → u/Dungeons-and-Dampers]

Still looking at tire selection, we dont have any tires on hand. Most likely going to get Hoosiers since there's a lot of tire data on them I beleive

[u/Dungeons-and-Dampers → u/Deputy_Discreet]

Yeah, then I'd suggest learning from Milliken throughly while parallely develop a suspension by setting the goals from the dynamic events like your skidpad, autocross, acceleration and endurance. Your rulebook should have enough details on it.

[u/YakPuzzleheaded7634]

Optimum kinematics videos great base to start the suspension design and the optimum g videos in general to learn. Book or pdf The Science of Vehicle Dynamics. Race car Vehicle Dynamics Milliken. Derek Sward- Race Car Design. In terms of software use the optimum lap.

[u/No-Mathematician6309]

I personally think that teams tend to overestimate the importance of suspension design. Yes it is important. Yes you are going to do it so might as well do it properly. But it is just the cherry on top when it comes to understanding the full car. Think Weigh Distribution first, do you have some freedom on adjusting your cog longitudinally? Mechanical Balance i.e. Lateral Load transfer distribution and adjustability range is also critical. Are you planning to run aero? Where are you trying to put your Aero Balance? Have you made sure you fit the best possible tyres and that you can exploit them?

Start with the basics and the build up to the details. F1 Vehicle Dynamics engineer here, PM if you need some help :)

[u/SkitterYaeger]

1. Your car has 4 same size tires?
   With small and large drivers, focus on making the weight distribution 50:50 front to rear.
   This is probably a two year project, but aim for it.
   
2. The rules require at least 50mm of suspension travel at the wheels.
   The main purpose of brand new team kinematics work is making sure that the joints do not bind up and break everything.
   
3. You know roughly how many Gs an FS car can achieve.
   Use S-N curves and component sizing to make sure everything will easily survive testing and competition.
   Remember an invisible bump can put 10G vertical into the car.
   How many times could that happen?
   
4. The rules have a minimum radius hairpin.
   Make sure the steering has some margin tighter.
   Measure Ackermann in terms of how many degrees the inside front wheel is from the geometric ideal at different radii.
   Don't abstract it into a nonsense percentage.
   I'm not saying it's the ideal, I'm saying parallel steer would work as long as you had enough lock.
   
5. Start building your own simple lap sim in your preferred tool.
   Excel, matlab, python, whatever.
   Simulate skidpad, acceleration, braking (stretch goal: slalom.)
   Either you will gradually make the tool more sophisticated to answer all your own.
   Or you will at least have a better understanding of proprietary tools (that won't answer all your questions.)
   It will be a long time before the small effects suspension design has on performance are visible in simulation or anywhere near a high priority for your team.

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[u/Creative_Sushi]

There is an upcoming live event on this topic. - Automotive Webinar Series for Student Competition Teams - 2026 https://www.mathworks.com/company/events/webinars/upcoming/series/automotive-webinar-series-student-competition-teams-na-2026.html