The best way is to do an "NVH" test with a "hammer" and use sophisticated software to extrapolate from "dynamic" stiffness to "static" stiffness at O Hz. I have always seen a great influence of the test result by the way the car was constrained to the rig (already for instance a hydraulic clamp...
As with many things the world is continuing it's developments in every area of mechanical engineering. Carbon has still a massive advantage in weight to strength ratio (and costs) but that comes largely into play on parts that are important for carrying loads. Obviously making a rear view mirror...
You must ask yourself what is "your" USP point for a company to "hire" your services:
"Expertise" ? You must have a proven track record and have the medals ... otherwise no manager can make an inhouse case for buying your services
"Speed" ? Difficult one .. this could be done by having...
I cannot help you on that one, If your problem is not "rocker linkage related" you might want to check out an alternative: www.dynatune-xl.com
Cheers,
Dynatune
I'd like to add my 2 cents: at 0 speed, so not at medium speeds, another parameter of the tire, the so called "bore" moment can be sensed in the steering (there is no "classical slip angle" at 0 speed so no "classical aligining torque due to pneumatic trail" and this "bore" moment is also...
Easy to ask, difficult to answer, here a few thoughts
1) How about aerodynamics of the car ???????? .....As mentioned Drag helps but Lift makes things worse .... could be worse could be better at 30 mph ..
2) How about tire contact patch deformation of the tire due to centrifugal forces ? ...
Looks to me that you are trying by "trial" and error to "lock" in into your best Ackermann percentage (which is not a bad thing at all). Ackermann is defined ideally for a "static toe" of 0 and any value different from that value does change your percentage Ackermann quite drastically. So by...
That is a nice one :-) and can be solved by using Laplace Transformation.
If you want a virtual post-rig already developed have a look at the software DYNATUNE on www.dynatune-xl.com
Cheers,
dynatune, www.dynatune-xl.com
Chris,
I can give you a few rules of thumb for Yaw Inertia. Yaw and Pitch Inertia are any very close.
1) On average the radius of giration for yaw of a car is around 45% of the wheelbase - my own database of vehicle measured.
2) I once found an ancient german formula to estimate yaw...
Depends on what you want to achieve with a "no droop" front or rear end. The "trick" is very old but not well known and allows one to change the balance of the car drastically to understeer or oversteer depending on what end of the car the droop stops acts first. In the late 90s and early 2000nd...
Golfpin,
sorry for not being clear in my terminology. I am using the typical "german" definitions since I was educated there. Pro-Ackermann is indeed "normal" positive Ackermann and Anti-Ackermann is the equivalent to negative Ackermann. The % indicates how much the inside wheel "follows" the...
Golfpin,
Yes, as far as I am "updated" F1 still typically runs Anti-Ackermann (except for Monte Carlo) but that is in my opinion more due to package reasons as for pure performance reasons. The general idea behind negative Ackermann is to fruit better the higher vertical load and tire friction...
Golfpin,
Thank you for the kind words. As a "teacher" it does make a lot more fun to have "students" that are willing to learn :-) ...
I have lived and breathed suspensions (and cars) now for more than 25 years and I had the fabulous opportunity when I was a starting engineer that I came to...
Unless you design 100% anti-dive in the front suspension and 100% anti-lift in the rear suspension you will always find the roll center going down at the front and coming up on the rear under braking, which will balance your lateral load transfer distribution towards the rear of the car, making...
Maybe this extra info could help you guys understand Suspension's better:
Just let go of all links and so on, just concentrate on the knuckle/upright. The "vertical" movement of the knuckle/upright can be seen as a rotation around an axis. This axis may be nearby or far away. This axis is...
Yes, as far as I can follow it is correct. It is important to know that caster angle and King Pin Inclination angle do interact on suspension characteristics. The matter is far from simple - but that is the fun part -and soon you will be able to have a tool that does all that for you. I am...
OK, I can see it now clearly.
I would suggest to run a static toe-sweep from (-0,5°, 0° and 0.5° total static toe) to see what happens to your understeer. If the results are "massively" different I would look into Ackermann, if they are "so and so" I would not be too worried about Ackermann...
Typically a (modern)McPherson type Strut is designed to have around 4° of caster and 8° of King Pin. On racecars like the Seat the King Pin increase comes basically from package reasons in order to fit racing brakes, increase track width and permit wider tires whilst the increase of caster is...
