Does anyone know what the centre of gravity height is for a Locost roughly? very technical i know!
different for every car, Id guess about 5-6 inches from the base of the lower chassis rails through the crank, box and diff.
Wheels and brakes are blow this, bodywork, top end of engine and more than half the chassis are above it.
I would of said marginly lower on my car 4-5 inches from the top of the bottom rail as with gearbox and diff diff on that mark, and 1/2 an engine
above,
with out the engine there isnt much weight above the lower rails anyway
It would be intresting to actually find out, but how ?
i would say (as a complete guess) almost somewhere around the line of the crank/gearbox/prop. perhaps slightly above
quote:
Originally posted by steve m
It would be intresting to actually find out, but how ?
100posts? Get back to work.....
But no, i two would imagine it to be about where most have stated.
- Another way to work it out crudely would be measure the mass and location of the center of mass all key items, Engine/Gearbox, Diff, Chassis, etc
and then calc.
- Although without a lot of work and attention to detial you could proberbly imagine simular to simular accruacy.
Another way to measure the hight of the CG if you have a set of scale (ideal four, that are fairly accurate) is to measure the corner weights of the
car, then to raise one side (or the front/rear) 2ft or simular (a known amount anyway) and remeasure the corner wieghts. Then calculate your heart
out.
Thats what they do at JCB for there diggers.
Daniel
quote:
Originally posted by dhutch
100posts? Get back to work.....
But no, i two would imagine it to be about where most have stated.
- Another way to work it out crudely would be measure the mass and location of the center of mass all key items, Engine/Gearbox, Diff, Chassis, etc and then calc.
- Although without a lot of work and attention to detial you could proberbly imagine simular to simular accruacy.
Another way to measure the hight of the CG if you have a set of scale (ideal four, that are fairly accurate) is to measure the corner weights of the car, then to raise one side (or the front/rear) 2ft or simular (a known amount anyway) and remeasure the corner wieghts. Then calculate your heart out.
Thats what they do at JCB for there diggers.
Daniel
I don't know where it is, what baffles me is why anyone would want to know
To design suspension for minimum roll ?
I think mine's with all my 13mm sockets and 3mm allen keys somewhere in the garage. I'll find it one day!
balance the car on the 2 wheels of one side & take a photo from the front.
Do the same on the other side - take another photo.
Measure the angles with a protractor.
Seemples
Actually I've been meaning to do this with mine ever since I built it...... maybe one day ;^)
you need to know height of CG to work out your braking properly & if you want to calculate roll couples & stuff...
[Edited on 5/11/09 by Bob C]
http://www.longacreracing.com/articles/art.asp?ARTID=22
Paul
quote:
Originally posted by Aled_g
Does anyone know what the centre of gravity height is for a Locost roughly? very technical i know!
300mm measured on my car using corner weight scales. I went to silly extremes to get it low so it might be a little higher on a "standard" locost
Hi
It is in general quite a bit higher than most are thinking it is. And remeber that you have to include the drivers weight unless building a remote
control version. And full roll cages espesialy the 45mm ones make a huge difference to the outcome.
Cheers Matt
I'm with procomp on this one, cog is a hard one to call in a cr that weighs so little and the driver can make a massive difference.
are you looking at this from a racing point of view? what type of roll cage will you have? a full 4 leg cage will raise your GOG massively, a 2 leg
not so much but still significant, how much do you wiegh? what size fuel tank will you have and how low can you get away with mounting it?
really every home built car, cobbled together from different parts and assembled for different porposes will have significantly different COGs. how
long is a piece of string?
Indeed. My tube frame, composite shell, mid-engine Mini was at 16" for CG.
One thing people need to keep in mind is that CG isn't about what stuff weighs, it's about where it's distributed. A plastic hollow
model shell of a car that weighs 1kg has the same CG as one made of lead.