Where did you read that the friction co-eff for rubber/asphalt is .35?
Either way, the model of friction you get taught in high school is incredibly basic, (called Coloumb Friction if memory serves) and only applies to notionally rigid bodies ( so Coloumb friction works pretty well maybe for railroad wheels on steel tracks).
But if the Grip = Mu*Load equation held up in the real world, then trucks could drive around on a set of 4 180mm wide hatchback tyres and have just as much lateral grip as any other vehicle.
In reality, rubber on asphalt acheives its grip in two ways, one called hysteresis, which i dont pretend to understand but is to do with the way the contact patch deforms under load (which is not the case if you just took a solid block of rubber and rubbed it against some asphalt).
And secondly adhesion, which is basically stickiness. The molecules of the rubber stretch and interlock with the molcules of the road surface, like microscopic velcro. And this effect is larger with softer stickier tyres and higher temperatures.
So G forces higher than 1 in non aero cars are acheived by effectively 'sticking' to the road, rather than just resting on it in the traditional friction model, and in aero cars higher G forces are acheived because even though your Mu might only be 1.3, the load on the tyre is no longer proportional to the mass of the car because of the aero load, so the grip force can be much higher.
But as this force is still only accelerating the same mass, the rate of that acceleration is much higher.
Either way, the model of friction you get taught in high school is incredibly basic, (called Coloumb Friction if memory serves) and only applies to notionally rigid bodies ( so Coloumb friction works pretty well maybe for railroad wheels on steel tracks).
But if the Grip = Mu*Load equation held up in the real world, then trucks could drive around on a set of 4 180mm wide hatchback tyres and have just as much lateral grip as any other vehicle.
In reality, rubber on asphalt acheives its grip in two ways, one called hysteresis, which i dont pretend to understand but is to do with the way the contact patch deforms under load (which is not the case if you just took a solid block of rubber and rubbed it against some asphalt).
And secondly adhesion, which is basically stickiness. The molecules of the rubber stretch and interlock with the molcules of the road surface, like microscopic velcro. And this effect is larger with softer stickier tyres and higher temperatures.
So G forces higher than 1 in non aero cars are acheived by effectively 'sticking' to the road, rather than just resting on it in the traditional friction model, and in aero cars higher G forces are acheived because even though your Mu might only be 1.3, the load on the tyre is no longer proportional to the mass of the car because of the aero load, so the grip force can be much higher.
But as this force is still only accelerating the same mass, the rate of that acceleration is much higher.
1) Not at the moment.
2) To an extent yeah. The kind of red-block pavers in south city around the tram tracks definitely have less grip, and I've always felt that Fern Bay was less grippy that other tracks (cos of the sand I guess) but I cant prove that.
3) Already answered.
4) 0.74 Kg/l in LFS as best as I can calculate.
5) No, but it sounds like either driver or heat issues.
6) The average cruising airspeed velocity of an unladen European Swallow is roughly 11 metres per second, or 24 miles per hour.
Nah, RAF data is generated by the physics engine from MPR/SPR data. And I believe that MPR/SPR data is made up mainly of the control inputs. So the only way to generate it realtime would be to replicate the phyics engine. Which is impossible, natch.
I would love to see the outsim packet expanded to include real-time telemetry, but I'm not sure if it would be a good idea because it potentially opens the door to outsim based cheats like traction control and anti-lock braking.
I would love to see the outsim packet expanded to include real-time telemetry, but I'm not sure if it would be a good idea because it potentially opens the door to outsim based cheats like traction control and anti-lock braking.
Well the credits you earn online are stored online, but it doest sync with your local machine. If you go to LFSWorld it will tell you your online credits.
Ah, but look on the bright side, he's back on the treadmill, and once the language patches are done, Physics will follow 
It depends largely on the suspension geometry. A particular geometry will have a characteristic camber change profile throughout its movement, and the ideal ride-height and roll stiffness combination will match up with that to provide the best live camber it can during roll.
If you move the ride height a long way from the ideal position, the the camber change during roll will be different and may well be giving away the little bit of extra grip you got from lowering the COG.
If you move the ride height a long way from the ideal position, the the camber change during roll will be different and may well be giving away the little bit of extra grip you got from lowering the COG.
Yeah, but in this case, Logitech Gaming Software is your friend (if you have it). You can record key commands in LGS, then create 'cycle' commands that basically run through a number of key presses. I have one button that cycles tyre/damage/off and another than does live settings/strategy/off. Works pretty well.
But yeah, I'd agree that for people who arent using a logitech wheel, it would be helpful.
But yeah, I'd agree that for people who arent using a logitech wheel, it would be helpful.
I think he is actually referring the the third force that a tyre generates after lateral and longitudinal force. Ie a tyre which has slip angle generates a torque around its contact patch in addition to linear forces in the ground plane. This is generally referred to as self-aligning torque or aligning moment. I would be pretty suprised if it isnt modelled in the tyre model, as even straightforward Pacejka models in Racer and ISI models produce it.
Obviously, this force is a component of what you feel through the steering wheel (although actually a pretty small one, as cars with zero-scrub angle and low caster will prove).
The larger component of steering column torque is generated by the fact that the linear tyre forces are applied some distant away from the steering axis itself, so this creates a torque around the steering axis. And the larger the scrub radius and caster, the bigger the distance between the contact patch (where the forces are generated) and the steering axis's intersection with the ground.
Thinking about it, I'm not sure what the effect of aligning moment on the steering column is. Obviously a linear force applied a distance away from an axis results in torque on that axis, but surely a torque applied some distance away from an axis actually results in a linear force on that axis?
Which begs the question, do aligning moments in tyres even result in torque in the steering axis?
But just to return to the original question. FF definitely account for castor, inclination and scrub radius in its generation of FF forces. In S1 these values were independently variable (urealistically) and you could clearly feel the various effects. If you arent feeling anything at the moment, then its possible you've some kind of technical problem.
As for the effect of tyre aligning moments, then I'm not sure, but I dont think they have a large effect on force feedback.
Obviously, this force is a component of what you feel through the steering wheel (although actually a pretty small one, as cars with zero-scrub angle and low caster will prove).
The larger component of steering column torque is generated by the fact that the linear tyre forces are applied some distant away from the steering axis itself, so this creates a torque around the steering axis. And the larger the scrub radius and caster, the bigger the distance between the contact patch (where the forces are generated) and the steering axis's intersection with the ground.
Thinking about it, I'm not sure what the effect of aligning moment on the steering column is. Obviously a linear force applied a distance away from an axis results in torque on that axis, but surely a torque applied some distance away from an axis actually results in a linear force on that axis?
Which begs the question, do aligning moments in tyres even result in torque in the steering axis?
But just to return to the original question. FF definitely account for castor, inclination and scrub radius in its generation of FF forces. In S1 these values were independently variable (urealistically) and you could clearly feel the various effects. If you arent feeling anything at the moment, then its possible you've some kind of technical problem.
As for the effect of tyre aligning moments, then I'm not sure, but I dont think they have a large effect on force feedback.
Last edited by colcob, .
*cough* http://www.ebuyer.com/customer ... WV3&product_uid=57716
Nevertheless, I can tell you from experience that plasterers do not appreciate being electrocuted one bit. Although the sparks were impressive. Good job floats have rubber handles really.
Nevertheless, I can tell you from experience that plasterers do not appreciate being electrocuted one bit. Although the sparks were impressive. Good job floats have rubber handles really.
No. Definitely not safe for release. It would certainly turn the endurance leagues into a frenzy of paranoia about whether other people were secretly running 110-120% stints to give themselves the edge.
Would be safer to keep it to youself and just wait for the inevitable patch that fixes the AI.
Would be safer to keep it to youself and just wait for the inevitable patch that fixes the AI.
Well I could see a system whereby no component will 'randomly' fail without some driver influenced damage being inflicted upon it. But ONCE some damage has been caused, the probability of certain types of failure becomes activated. Then the actual probability of total failure is influenced by how seriously damaged it is.
Ie. You would not expect a perfectly undamaged wishbone to just snap randomly, but if you've inflicted 10% damage on it, maybe there is a small chance that it would just fail. And if you've bent the thing halfway up to the body work, then there is a pretty high chance that it might completely fail on the next kerb.
Because at the moment, even once you've damaged your car, that damage is static, whereas in reality damage can become either degenerative or catastrophic, depending on the type of component (ie a carbon fibre wishbone is either completely intact and functional, or completely broken, whereas an engine can have degrees of brokenness, and once damaged can get worse by itself).
Ie. You would not expect a perfectly undamaged wishbone to just snap randomly, but if you've inflicted 10% damage on it, maybe there is a small chance that it would just fail. And if you've bent the thing halfway up to the body work, then there is a pretty high chance that it might completely fail on the next kerb.
Because at the moment, even once you've damaged your car, that damage is static, whereas in reality damage can become either degenerative or catastrophic, depending on the type of component (ie a carbon fibre wishbone is either completely intact and functional, or completely broken, whereas an engine can have degrees of brokenness, and once damaged can get worse by itself).
Just curious, why 305dpi rather than 300dpi?
Anyway, good idea, I might have a crack if I find the time.
Anyway, good idea, I might have a crack if I find the time.
Yeah, but you still arent telling us why you arent in 4SR anymore. Come on, we want gory details, dressing room bust-ups, multi-million pound contracts, we want drama damnnit
Coo, I wondered where swifty had got to.
Well good luck to them at 4SR.
So not that I'm one to gossip, but why is Will Dendy driving around in black skins like an old woman at a funeral telling everyone who'll listen that he's left 4SR?
Did you catch him stealing from petty cash again?
Well good luck to them at 4SR.
So not that I'm one to gossip, but why is Will Dendy driving around in black skins like an old woman at a funeral telling everyone who'll listen that he's left 4SR?
Did you catch him stealing from petty cash again?
Or, given that we have asymettric tyre pressures, you can put some stagger (or wedge) in like that.
For the record, my understanding of wedge is that the spring rates are altered asymettrically to result in the LF+RR and RF+LR corner weights being something other than 50%-50%.
For the record, my understanding of wedge is that the spring rates are altered asymettrically to result in the LF+RR and RF+LR corner weights being something other than 50%-50%.
First rule of the internet. NEVER post pictures of yourself (or your pets) on the internet.
Schoolboy error Scawen.
Schoolboy error Scawen.
Here you go. I got this off a guy called yankman online. He was running 42.1x with it, I can run 43.1x. Seems fairly drivable to me too, no nasty suprises so far.
I'm not sure I fully follow your analysis, but I can say that the frequency values in the spreadsheet are absolute, not per tonne. And the *1000 you see is simply to convert the spring rate from kN/m to N/m.
Personally I dont particularly hold the opinion that lighter cars need higher spring frequencies and heavier ones need lower spring frequencies, so I wouldnt worry about it too much.
Personally I dont particularly hold the opinion that lighter cars need higher spring frequencies and heavier ones need lower spring frequencies, so I wouldnt worry about it too much.
Well it wasnt skiingman who said that, it was me. And I think you'll agree I (and most of the contributors to this thread) can manage without an idiots guide to physics.
If one value equals another value times a constant, the two values can be described as analogous, ie they have a proportional relationship.
So as force*lever arm (a constant) = Torque, Torque is proportional to force. As Weight = Mass*g(a constant), weight is proportional to mass. Hence the statement :
torque/weight is directly analogous to force/mass which equals acceleration.
is entirely correct.
Or if you like, (torque/weight) * K = Force/Mass
where K= 1/(leverArm*g)
If one value equals another value times a constant, the two values can be described as analogous, ie they have a proportional relationship.
So as force*lever arm (a constant) = Torque, Torque is proportional to force. As Weight = Mass*g(a constant), weight is proportional to mass. Hence the statement :
torque/weight is directly analogous to force/mass which equals acceleration.
is entirely correct.
Or if you like, (torque/weight) * K = Force/Mass
where K= 1/(leverArm*g)
Yeah, but the scrub caused by a 500hp engine trying to rotate the rear wheels is vastly greater than the scrub caused by a fraction of a degree of toe, so I dont think you'd see much difference.
A clearer test might be to jump in the FXR, and do the same test three times, one with all the power to the rear, one with it all to the fronts (euch) and one with 50-50, and see what difference it makes.
A clearer test might be to jump in the FXR, and do the same test three times, one with all the power to the rear, one with it all to the fronts (euch) and one with 50-50, and see what difference it makes.
Looking nice Fordie. Look forward to seeing the rear end of Daves UFR skin on monday
I thats the fundamental point of misunderstanding that started this whole thing off. Me and bob were thinking of instantaneous acceleration values, and you were thinking of acceleration over time, which granted is how most people probably think of acceleration.
I think also its more accurate to say that the overall acceleration over time is the integral of the tractive effort curve for the speed range, not the torque curve for the rev range.
This obviously includes the gearing effects, so your single speed engine would just have a straight, descending line from its CVT gearbox, with a bit fat area under it
I think also its more accurate to say that the overall acceleration over time is the integral of the tractive effort curve for the speed range, not the torque curve for the rev range.
This obviously includes the gearing effects, so your single speed engine would just have a straight, descending line from its CVT gearbox, with a bit fat area under it
Last edited by colcob, .
Yeah, but remember that torque at the wheels = engineTorque*gearRatio.
So for a given speed, if you run at a higher engine revs, you run a lower gear ratio. Which, if you are running at max power RPM, will result in greater wheel torque.
So for a given speed, if you run at a higher engine revs, you run a lower gear ratio. Which, if you are running at max power RPM, will result in greater wheel torque.
Yeah, I have c-panel on my hosting and there are about 15 different stats packages installed including commercial Urchin Stats which is ace.
Presumably this offer is the same.
Presumably this offer is the same.
FGED GREDG RDFGDR GSFDG