Thread: Centre of Gravity: Balance Point

out of interest, why would we need to know the CoG

Originally Posted by slug_burner

Hans,

Based on the axle weights and 110 and 127 inch wheel base I calculate that:

for the 110 the CoG is approx 1060mm for the standard cab and 1067mm for the heavy duty cab, behind the center of the front axle.

for the 130 the CoG is approx 1311mm for the cab and 1386mm for the dual cab, behind the center of the front axle.

what is the height?

Originally Posted by weeds

out of interest, why would we need to know the CoG

So you can airlift one or build a see saw out of one.

Originally Posted by uninformed

what is the height?

According to the document linked earlier the kerb weight CoG height is about 665mm for all the four variants whereas at GVM it gets up to about 1m.

Are we talking 'Static' or 'Dynamic'?

If the car is moving, so will the CoG. That's how you get phenomena such as 'Lift off Oversteer'. CoG shifts forwards, back end goes light, blah, blah... "Oh! Hello fence!"

M

Originally Posted by slug_burner

According to the document linked earlier the kerb weight CoG height is about 665mm for all the four variants whereas at GVM it gets up to about 1m.

I opened the first link....I couldnt make sense of it....just looked like dates of press releases or such????

Originally Posted by camel_landy

Are we talking 'Static' or 'Dynamic'?

If the car is moving, so will the CoG. That's how you get phenomena such as 'Lift off Oversteer'. CoG shifts forwards, back end goes light, blah, blah... "Oh! Hello fence!"

M

I think you know the answer, static. Global movement will not change the CoG, you have to have relative movement of weighty parts to get any change. How do you get the CoG to move forward? I can picture minor vertical movement of the CoG as a result of the suspension allowing the axle assemblies to move relative to the chassis/body but having difficulty picturing fore and aft movement of the CoG solely due to suspension movement.

Originally Posted by weeds

out of interest, why would we need to know the CoG

very handy to know the cog, especially when travesing side slopes, the Cog Height looking from the front or rear is directly related to roll over angle.

For example using figuires I plucked out from where the sun dosent shine an unladen Defender with a low 665mm cog the car will roll over on about a 45 degree side slope, a laden vehicle with a 1m cog will roll at about 40 degrees and if youve got 250kg on a roof rack your cog will be about 1.5m and your roll over angle might be 32.5 degrees.

I'll get a protractor out & work it out properley just for interest.

edit, actually someone else has already done the protactor thing,
check this very excellent webpage out http://www.jeepaholics.com/tech/cog/