sagjohnson

(originated in CGT/4k forum)

You know in our trunks there are the two structural beams running longitudinally? Well, my idea is that that would be a good place to mount an automatic counterweight to increase stability in cornering.

I once saw a documentary on skyscrapers where one had a monstrous counterweight installed on the top floor to stabilize the building when it was being swayed by the wind.

My idea is to have a heavy, say 50 pounds or so, counterweight suspended between the beams in the trunk by two (or more) hydraulic or electric sliding shocks. Two mercury switches could signal the device when the car is turning in a certain direction (via inertia, g-force, bla bla).

When one of the mercury switches is triggered, it activates the device to push the 50 lb counterweight in the opposite direction of the turn. It would need to be fast reacting, but I think this could be simplistically designed and built.

This would not only stabilize the car in turns for obvious reasons, but it would improve the weight ratio between the front and rear wheels. Yes, it adds poundage to the car, but not much, and the benefits...

What do you think?

jop

which would look kind of odd

My rudimentary reasoning:

If the weight can't move beyond the inside tires, then best case is, it loads the inside tire, and doesn't affect the outside tire (because the inside tires are effectively a fulcrum).

squidix9

Are suggested for allowing dynamic ballast.

It has been suggested to allow fluid tanks where ballast could be shifted from one area to another to improve weight distribution.

I have not heard of as novel an idea for weight shift for cornering as you propose.

One key to balance and handling is indeed weight distribution. But this can be achieved in much simpler ways.

By balancing weight for-aft, and carefully controlling the bounce and rebound of yor suspension you can get quite good handling without the use of a dynamic system. A car that has a very neutral setup can be made to over or understeer as conditions warrant. There are many good resources on the web, which describe handling conditions, and the way to cure them.

With a neutral setup, I can either induce oversteer or understeer, depending on my gear choice, and how I enter a turn. This makes more sense than having a dyanmic setup, for me at least.

<img src="http://members.verizon.net/~vze4phja/images/coversm.jpg">

Even a nose heavy car like the Quattro, can be made to have balance and fly like the wind!

Electron Man

Bad idea..."weight is the enemy"

SKS

wear a WWII helmet and lean your head.

süpercüp

move your battery to the trunk and have it slide

squidix9

With my first rally car, at an event up in Canada.

Oh, you mean the BIG bolts hold it down, not the small ones...

George Burdell

i think this has been DTM before

Lightweight-USPowah

I kinda play with the mass dampener idea when Im on the subway.. Its actually pretty cool.. Train stops and instead of my body going toward the front of the train, the force of deacceleration is transfered to my arms to the backpack where the force causes the backpack to sway along with my arms.. Ive been thinking about these a lot and have been trying to figure out how the hell they actually work which is why I played with the idea on the subway.. A friend of mine is big into dampeners, he actually designed/worked on a few projects for some NYC buildings.. There are also fluid dampeners (think giant bath tub on one of the top stories of a building, got to see one in the begining stages of construction on my last site visit)... Okay, as for why it might not work on a car.. Momentum.. My thinking is this... Run with a tank filled with water run down the hallway and try to stop.. Whats going to happen? When you stop the water is going to transfer from the back of the tank to the front of the tank causing you to topple over... Now, in a car its a totally different environment.. when you turn right hard, the weight is going to slide to the left side which means your increasing the lateral force in the opposite direction that you want to you.. It won't work the same way in a car as it does for a building.. If I remember correctly, the way it works for a building is that building sways faster the the weight therfore the weights force is exerted in the opposite direction of the wind force causing the dampening effect..

ModifiedA4

...in a building it is to prevent a tacoma narrow's bridge type event from happening. Since there is no fequency here (during corning) there is nothing to damp.

You are thinking of an active ballast, which is completely different than the builing analogy.

I think it would be easier to make a control system connected to 4 airshocks to alter suspension dynamics, ala saab.