CoG (Center of Gravity)?

[Visket]

This should be a CoW (Can of Worms)...

I'm sure the answer is available, and I've asked my Guide and Service Manager, both the no avail.

If I were to point my index finger on the outside of the driver or rear passenger door, how far up from the bottom of the door sill would my fingernail touch? How far back from the front edge of the driver's door sill?

I have seen videos of how to mathematically determine the front/rear CoG by weighing the vehicle at each axle, then tilting it up/down a certain number of degrees, weighing again, and running some numbers. Any such tests you know of?

DISCLAIMER: Yeah - I know I'm overthinking it. I know "it doesn't matter". I know the ride height will effect CoG, so give me the answer at 9.5" and 15.0", eh? I know some of you "don't know", so no need to tell us that. I'm not holding anyone legally liable in case I go 1 degree less and tip it over. I know rocks will pop-up and roll you over like a dog wanting a belly rub. I know. I know...

OK - here we go!!!

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[sub]

13.8 inches

 

[mkg3]

The attached info is from the original specs so things have changed a bit but not dramatically.

You just need to find the F/R distribution point and use the overall length to determine where the cg is along the vehicle. Cannot help you on the Z direction (cg height). That info requires more data regarding the weight distribution from the ground up to the roof top.

 

[Visket]

The attached info is from the original specs so things have changed a bit but not dramatically.

You just need to find the F/R distribution point and use the overall length to determine where the cg is along the vehicle. Cannot help you on the Z direction (cg height). That info requires more data regarding the weight distribution from the ground up to the roof top.

That's a great spec sheet. Looks like the 135K/wh battery has the best power-to-weight ratio...

Supposedly, that algorithm I saw (measure weight, tilt the vehicle, measure again, math math math...) would also calculate the height of CoG.

This is a good start, though. Thanks.

 

[FUBAR!]

The non-mathematical way I have done it with race cars is to just hang the car twice from two different points and drop a plumb weight from where you are hanging the car...where the lines intersect is your CoG...obviously only works for space frame vehicles and not very helpful - but interesting? maybe.

 

[jimmyb2]

I have been trying to get the same information via numerous emails a phone calls to Rivian. Have always been told that the info is not available. We need the help of someone who has a friend who is a design engineer for Rivian.

The COG is readily available via the CAD programs used in the vehicle design. We just need help from someone with access to that info.

The military HMMWV (Humvee) has a metal plate (similar to GVWR plate) that provides COG details. It would be nice if Rivian copied that.

 

[emoore]

I really have nothing useful to add just to ask that is the center of gravity really referred to as CoG in the auto industry. I’m used to just CG in my industry. Just an interesting curiosity.

 

[SciGuy]

13.8 inches

Funny how you have to qualify your question against the response trolls who claim people posting questions are trolls. Nicely done and I like your question.

 

[Gr8smiles]

Roll over angle in new off-road screen is helpful. As a pilot, weight and balance uses moment arm lengths to adjust Center of gravity. A bit more depth in programming could manually enter how vehicle is loaded. Then Show CG and roll over risks on angle gauges.

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