Help with physics assignment

optimusprime

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K`Tetch said:
You've got your static and dynamic friction, your equations of motion and all the rest to play with.
That's pretty much all of Uni mechanics right there.
 

GoP-Demon

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ahh I think I'm going to do the P2 since I also have to find a related printed article at my library...sigh
Right now I'm looking through magazines and hopping I can find one on the P2. Or on differentials...
 

K`Tetch

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That's pretty much all of Uni mechanics right there.
It is so sad that, in the US, that is the case. in the UK, you get taught about static friction and equations of motion as part of your GCSEs (the standard subject school-leaving exam taken at 16) whilst dynamic friction is part of A-level (a 2 year set of courses in 2-6 subjects taken between 16 and 18, and used to determine university entry as well)

Gop - you won't find anything about the prodrive diff - its something they built themselves. You will be able to find lots on standard diffs, however, and maybe a little about standard powered diff's as well
 

GoP-Demon

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yah I had trouble finding anything. I'm assuming it's just the abs of breaks. It's just like a computer controlled diff. Here's what I wrote....

The important system that Prodrive has developed for the P2 is an active differential. An active differential is much like a center differential and a limited slip differential. Limited slip differentials will allow the outside wheel of a turning car to spin faster than the inside wheel so that the turn is sharper and has less understeer. Since there is more friction on the inside wheel during a turn, a LSD will give more torque to the outside wheel. With a LSD sharper and faster turns are possible because there is more force on the outside wheel then on the inside wheel. TThe center differential helps corner exits and entrances so that when the car exits a corner more power can be given to either the front or rear tires when it is needed.
An active differential is the same concept as a LSD and center differential, but is computer controlled. The computer controls how much power should go to each wheel with three sensors: a steering sensor, a speed sensor, and a yaw sensor. The first two sensors are self explanatory. The yaw sensor is a sensor that detects what racing line you are taking through a corner. For the entrance of a corner if the computer thinks you are going to understeer into the corner (not turn enough because the front tires can?t grip since the car is going to fast into the corner) it will push more power and torque to the back wheels so that the front wheels of the car stop dragging the car in the wrong direction. If the computer detects that the car is going to oversteer (to turn but loose traction in the back tires making the back wheels of the car turn to wide) into the corner it will give more power and torque to the front wheels which will allow the driver to start steering out of the corner. If the computer thinks the car is going to start spinning it will give more power to one wheel so that the car stops sliding by letting that one wheel push the entire car out of the spin. The computer can detect any of these things by measuring your speed, your turning direction, and the racing line you take. With the active differential the car has maximum control and grip.



I can be wrong o_O so don't use this as a learning thing. And uhm tell me anything I can change :p
 
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Peter3hg

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Here's what James may says about the active diff.
Ah, now the active diffs. Yes, there's one of these in the middle of the car and another one on the back axle. The middle one controls what proportion of the torques from the engine go to the back wheels and what proportion go to the fronts. And the diff at the back does the same, splitting the torques between the rear wheels. They're both controlled by a very clever computer that has a speed sensor, a steering angle sensor and something called a 'yaw sensor' which sort of measures the line that the car is taking through a corner. This is very important. If the computer looks at your steering angle and then the yaw sensor tells it the car is turning through the corner less sharply than it should be for that amount of steering lock it thinks, 'uh-oh, that's understeer'. Then it telegraphs the centre differential and tells it to make sure more torques are going to the back axle so that the front stops dragging the car wide, like a front wheel drive car would. But then, as the car leaves the corner it tells the centre diff to push more torques forward to pull the car out of the turn without oversteering like a rear wheel drive car would. Hmm, yes, that sounds about right. Ah, and the active rear diff helps you out in sudden changes of direction so that if the car is looking like it might spin, the computer can step in and push torques to one wheel to push the rear of the car back on line. And all this computer thinking and moving of torques can happen in milliseconds. It's very clever. It's also made my brain hurt."
 

NecroJoe

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Hmm...using the P2 as a topic, seems more like an engineering paper, than a physics paper...just me...

I would think a better topic would be the lawn-darts-with-cars thing...you have acceleration, inertia, trajectory, etc.
 

andoxviii

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What about the winter olympics episode (season 7 episode 7, I believe) where they tried to make the old mini jump farther than a skier down the hill?

Plenty of physics involved, and they actually show diagrams and explain what's going on fairly well.

Good luck.
 

GoP-Demon

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after much consideration my second journal will be done on the mini ski jump. There is just so much explanation :O
 

HondaF1

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Maybe you can explain the physics involved when James slid down then ramp?? :D
 
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