Leading Edge MotorSport
What We Do
Set-Up Sheet
The Store

Vehicle Dynamics

You'll hear us talk about vehicle dynamics quite a bit in these "lectures." So we should start with a definition. Vehicle dynamics is how all the bits come together. It's a broad category which covers virtually everything Leading Edge Motorsport does: the interrelationships of the chassis components, the concept of controlled vs. uncontrolled springs (when does the stiffness come in; when do you want it to, etc.)

The importance of vehicle dynamics comes down to three core areas: 1.) Internal - how the pieces interact, your set-up; 2.) External - how the set-up reacts to the road; 3.) The psychology with which you approach your study and implementation of these two areas.

You'll read masses of information about Internal -- the components themselves. You can (and we will in future sessions) study the formulas, the different approaches to designing the hardware, the equations which 'predict' how everything will work when you've got the pieces in place. We'll offer "Recommended Reading" in these essays (and have a direct link with amazon.com so you can order those volumes that interest you.)

However, there's not much written about the fact that when you have your math done, and you're looking at good, solid numbers that should work, they don't. The External aspects of vehicle dynamics is the study of the fact that what the numbers are focused on isn't what's under your tires. It's very easy to get lost in the "science" -- if you don't remember it boils down to those paperback sized areas - the contact patches. That's the problem with dynamic systems. And the reason for the lapse is that you have to Assume - make quite a few assumptions, actually -- if you're going to actually go out and do anything to your car. If you're trying to draw a conclusion from many variables, you have to use assumptions. But with a large number of assumptions it's inevitable that some will be wrong.

It's important to recycle yourself back to the start, to remember that your object in finding a vehicle dynamics solution is to make things stick. We tell clients to apply a deliberate, formal "Decision Loop." It's the same as a mnemonic; it's just a checklist to give you a repeatable, consistent order to the process you're undertaking every time you change something. When you apply the decision loop to your self-check you ensure that the answers come out in the same matrix. This lets you extrapolate the answers you seek from the differences you observe in the two (or more) answer sets.

The third area - the human dimension comes up when, for example, you think the car needs more camber, so you keep dialing in camber until you hit the springs. At that point you realize there has to be another answer. Keeping a book that documents the decision loop each time around isn't just about the hardware. It's about attitude. A book (in the decision loop format) is what you do to get ready to do what you must to get the car ready to do what it needs to do on the racetrack. A book reminds you to monitor the process constantly. In a dynamic system, you can't just "set it and forget it." And when things go wrong, it's ridiculous to blame the machine. Machinery is machinery. It doesn't have good days or bad days. Bad days result when you stop paying attention. When you work, and focus, within the limits of what the machine is capable of, you'll see results. The people-car interface -- the driver, the crew, the owner, everyone with anything to do with the car -- is something most books don't cover.

This leads me to a sidenote. I often talk to clients who are very clear about the limitations of their budgets and the time/effort they are able to invest. But it's the rare one who is satisfied with the performance limits those requirements dictate. Capability in a machine is totally dependent on the time and money invested on making the machine work in a particular way. If your priorities don't - can't, whatever - include the time and money at the top end, you HAVE TO accept something less in performance.

Vehicle dynamics covers everything and anything in how an automobile acts and reacts. Internal, external and the human element. To understand dampers, springs, wheel rates, brakes and grip (etc. etc.) you need to begin by taking a look at each of these areas.

Back to LEMD University

Vert Spike
Home || What We Do || LEMD University || Techniques || Set-Up Sheet
LEMD News || The LEMD Store || FAQ || Leading Edge Marketing

Copyright 2010 Leading Edge Motorsport. All Rights Reserved
Website Designed by Harbour Light Productions
Website Hosted by Tidal Media Group