critical speed

[cassiano]

CAN ANYONE HELP ME WITH MY DOUBT, I 'D LIKE TO KNOW ABOUT THE CRITICAL SPEED, THE CAR WILL BE UNSTABLE ABOVE OR UNDER THE CRITICAL SPEED?
THANKS

[cassiano]

CAN ANYONE HELP ME WITH MY DOUBT, I 'D LIKE TO KNOW ABOUT THE CRITICAL SPEED, THE CAR WILL BE UNSTABLE ABOVE OR UNDER THE CRITICAL SPEED?
THANKS

[PatClarke]

Mach 0.98

Pat

[luxsosis]

The car will definitely be unstable under the critical speed. You must maintain at least 60 km/h or your car will burst into flames.

[MileyCyrus]

I always thought it was the other way around, that your car would become unstable above critical speed being 88mph. Going above this will cause your car leave a trail of fire and disintegrate, reforming sometime in the future.

[DougMilliken]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">...UNSTABLE ABOVE OR UNDER THE CRITICAL SPEED? </div></BLOCKQUOTE>
See "Race Car Vehicle Dynamics" p. 177. The instability is defined for fixed control (fixed steering). In the real world it typically means that, above critical speed, the driver will have to vary the steering (saw at the wheel) to maintain a constant radius path for the car.

If you don't have our book, maybe your library can purchase a copy? http://www.millikenresearch.com/rcvd.html

ps. No need to YELL to get an answer around here...although ALL CAPS often generates silly replies.

[BillCobb]

A vehicle is only unstable in open loop control if the amount of oversteer exceeds a value defined by its wheelbase, 9.806 and 57.29xx. There's a square root in there, too.

Thus a vehicle with oversteer traits may not necessarily be unstable as is the usual annecdotal belief by the uninformed. The fact that it has a finite wheelbase gives in an element of stability.

An understeering car has no critical speed but has a characteristic speed in which the steering gain (g per deg) is down by 2).

In another example, my two horses are currently out in my back pasture and not in the barn, hence they are unstabled. This can be critical if your vehicle has more than 2 horsepower. If they get into McDonalds french fries (actually deep fried square roots) they get REALLY unstabled and shit flies all over the place. I recommend an understeering horse powered vehicle for novices. Yeah, I know, potatoes are actually tubers and they are the most fun behind a fast bass boat.

[cassiano]

I am sorry that idea was not to seem like a yell. next time i ll not do it.

thanks about the answers everybody

[Drew Price]

QFT. The funniest damn truth I may have ever heard.



<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillCobb:

In another example, my two horses are currently out in my back pasture and not in the barn, hence they are unstabled. This can be critical if your vehicle has more than 2 horsepower. If they get into McDonalds french fries (actually deep fried square roots) they get REALLY unstabled and shit flies all over the place. I recommend an understeering horse powered vehicle for novices. Yeah, I know, potatoes are actually tubers and they are the most fun behind a fast bass boat. </div></BLOCKQUOTE>