Prototype gp500 physics model

[HornetMaX]

I mean it's easier to feel IRL than see it and it's certainly easier to control IRL than it is in a sim with no haptic feedback (although if the traction control is set to give 5% slip, it should always happen anyway). As soon as I feel the bike start to move I would be adjusting the weight I'm putting on the pegs and bars and shifting around to keep things rolling without having to back off the throttle... which is reserved for those moments when things have got really out of shape!

OK, I do agree with you then: lack of feedback is exactly the reason I was pointing as #1 to explain why sliding is hard in GPB.

MaX.

P.S.
I doubt traction control can be set in terms of x% slip, it's surely much more complex than that.

[Allen]

I mean it's easier to feel IRL than see it and it's certainly easier to control IRL than it is in a sim with no haptic feedback (although if the traction control is set to give 5% slip, it should always happen anyway). As soon as I feel the bike start to move I would be adjusting the weight I'm putting on the pegs and bars and shifting around to keep things rolling without having to back off the throttle... which is reserved for those moments when things have got really out of shape!

OK, I do agree with you then: lack of feedback is exactly the reason I was pointing as #1 to explain why sliding is hard in GPB.

MaX.

P.S.
I doubt traction control can be set in terms of x% slip, it's surely much more complex than that.

I'd hope that that is precisely what the TC system is doing, if I call for 100% throttle it should give me the maximum amount the tyre will actually transmit (excluding any consideration of wheelies etc) and that should be around 5% slip. if that happens to correspond to actually being 50% throttle, then that's what I'd expect (a few years ago Michael Rutter said something along the lines of he found it hard to persuade himself to just open the throttle 100% and trust the TC to not just give him 100%... ).

It would actually be interesting if Piboso could output both rider applied and ecu applied throttle.. then you could see just how much the TC can cut things

[BOBR6 84]

Does the new xbox pad rumble/vibrate in different ways at all?

Ladies?? 

That could give pretty good feedback as to what the tyres are doing.. If the vibrations and rumbles could be tuned to suit. For the riders knee too as klax said!

[girlracerTracey]

Without wanting to open up all this debate all over again..Allen have you ever played the gp500 pc game?

In that game controlled power-slides are easier to initiate and control. Although it will bite you big time if you pannick and come off the throttle too early. In that game I can "feel" the slide more discernably and act to control it. In gpbikes the transition from not sliding the rear to sliding feels too abrupt and and sharp to me. This transition in real life I think is more gradual and more controllable. A rider's response to rear wheel slides in real life is, as a result, more intuitive and is a more natural response I personally believe. Because at speed feeding in the throttle on the exit to a bend the rate of progression into a rear wheel slide if you are using the throttle carefully I think is more gradual..

What is your honest opinion on all this as an ex racer?

grT

[girlracerTracey]

Does the new xbox pad rumble/vibrate in different ways at all?

Ladies?? 

That could give pretty good feedback as to what the tyres are doing.. If the vibrations and rumbles could be tuned to suit. For the riders knee too as klax said!

In gp500 there is an audible noise I think when the rear wheel begins to spin up. But this has been lost in time in the progression from DX6 through DX7 to DX9. There was an audible "cue" in the original game I believe.

grT

P.S. I think the rear wheel slides in gp500 are slightly too easy to initiate. I want something harder but still accessible if you are really careful with the throttle. Particularly on the 500cc 2 strokes..otherwise we're not arguably riding them properly..as god intended. And by saying that I do not mean lurid 100 ft powerslides. I mean a usable degree of rear wheel steering exiting appropriate bends under the right circumstances..but with a "bite" if you misjudge it. 

[girlracerTracey]

Does the new xbox pad rumble/vibrate in different ways at all?

Ladies?? 

That could give pretty good feedback as to what the tyres are doing.. If the vibrations and rumbles could be tuned to suit. For the riders knee too as klax said!

I am driving with a wheel now as you know Bob. But tbh I wasn't getting any force feedback effects with my xbox one pad..maybe I needed a plug-in or something? I'm not sure.

[BOBR6 84]

My 2 cents is its hard to simulate because like allen said you cant shift your weight around the bike and use the footpegs.. Also having your knee on the floor can help control these things.

Also in most cases we are all controling the throttle on a trigger with this much modulation... |     |

I have know idea how the right balance could be found.. Tough and good debate! 

[HornetMaX]

I doubt traction control can be set in terms of x% slip, it's surely much more complex than that.

I'd hope that that is precisely what the TC system is doing, if I call for 100% throttle it should give me the maximum amount the tyre will actually transmit (excluding any consideration of wheelies etc) and that should be around 5% slip. if that happens to correspond to actually being 50% throttle, then that's what I'd expect (a few years ago Michael Rutter said something along the lines of he found it hard to persuade himself to just open the throttle 100% and trust the TC to not just give him 100%... ).

It can't be that simple, for the simple reason that a % slip doesn't give you the full picture.
First of all, a % slip is valid only for longitudinal slip (slip when you accelerate or brake on a straight line, no cornering).
To quantify lateral slip you use an angle (sideslip angle), which is obviously not a %.

And even if you're tempted to translate the lateral slip into a % (for example dividing the lateral slip by an arbitrary "maximum" lateral slip angle), then you have another issue: the two slip quantities combines. The tire can only produce a total force that can be used to generate a longitudinal force only, a lateral force only or a combination of the two.
The more you use the tire to accelerate/brake, the less you have to corner (and vice versa).

Eventually you could have something that tries to estimate the total force currently being generated by the tire and then compare this to the total maximum force admissible by the tire.
But even this doesn't translate to something easily understandable: that's why on all the TC systems you don't have a % setting or any other quantified setting, you just have a bunch of levels, 0 being less TC than N. No further details are provided.

Also, what influences a lot the feeling the TCS returns to the rider is not only "how much it allows you to slide", but also other things like how fast he kicks in (and kicks out): these are dynamics properties of the system, not captured by a simple "5%" setting.

GPB's TCS only has 3 exposed parameters (Min/Max slip and ThrottleSmooth, undocumented) but internally I believe GPB has many more.

It would actually be interesting if Piboso could output both rider applied and ecu applied throttle.. then you could see just how much the TC can cut things

That would be interesting, but its more a curiosity than something else. However it could be useful to detect potential weakness of the current TCS.
Anyway, these quantities are surely available in the bike's telemetry, so it may make some sense to have them in GPB too.

Does the new xbox pad rumble/vibrate in different ways at all?

It has some rumble motors under the triggers. To be honest I don't know if these replace the old rumble motors or are additional to them.
At any rate, Piboso was not very favourable of even using the old rumble thing to provide extra feedback (rider knee down, or wheel sliding, whatever).
If I recall correctly, there's also a technical issue (something like rumble not being usable with xinput), TBC.

I am driving with a wheel now as you know Bob. But tbh I wasn't getting any force feedback effects with my xbox one pad..maybe I needed a plug-in or something? I'm not sure.

GPB does not support rumble (what you call FFB, improperly) at the moment.
GPB supports only FFB, but this can't be redirected to the rumble thing of a 360 pad (or similar) unless you use some tweaked drivers.
Which, IMO, makes zero sense: the signal you will "hear" on your rumble motors will be the steering torque at the handlbars ... hmmm, yeah ...

MaX.

[girlracerTracey]

Also in most cases we are all controling the throttle on a trigger with this much modulation... |     |

I have know idea how the right balance could be found.. Tough and good debate! 

I agree Bob. With a trigger throttle and brake control is a less precise science. There's no argument about that. You haven't got the same length of movement in a trigger..I don't think there's really any debate to be had about that. It's a fact I think.

I think if this is going to be done at all it can only be done by careful experimentation and testing. I think it goes without saying that this is a difficult & complicated effect to build into the "game". To be fair also I think many people do not believe it is something that even needs to be addressed in the first place.

This is why I value the opinion of real life racers so much. Particularly guys who raced back in the 1980/90s. People like Allen.

grT 

[Allen]

OK Max, friction circles etc... .... it's just that whilst trying to simplify the basics of traction control, it's obviously NOT that simple, but the basic premise of max grip is achieved with around 5% slip as a total of grip slip ratio holds (so if you have a neutral throttle on and a nice two wheel drift, don't expect to be able to add any more throttle unless you can stand the bike onto the fatter part of the tyre first), first principle of trail braking, more lean = less brake, first principle of acceleration less lean = more throttle (up to a point.. ). And yes as a tyre wears the grip changes and so do the traction limits,  so as anyone who's wound open a superbike whilst bolt upright on a freezing day with a relatively worn tyre knows, every tyre has a limit... ultimately the way a tyre slides past it's grip limit is what gives a good feel (decent suspension setup helps there too).
An honest opinion, TC should be banned, it teaches bad riding practice (and we all know what happens when it fails... don't we Mr Pedrosa!)


grT, Yes I have GP500, yes it's easier to initiate and hold a slide and yes, I think the one drop off with GP-Bikes is and always has been (at least for the last 6 years I've been trying it) the lack of any rumble to hint at traction limits, I've tried several times to play with a wheel/direct lean, etc.... and it really does nothing for me.. but then I have never managed to get the hang of the on board view either (again some feedback would probably help that too)

[BOBR6 84]

Tracey you should take a look at what Hawk uk is doing with track surfaces, mallory park thread.. I fully understand what you want from gpbikes but at the same time its hard for me to commit to an idea and direction with physics.. Simply because everytime I play gpbikes something different happens.. Eg. When I started playing I couldnt do this and that but now alot of things make sense.. An the physics model is still suprising and impressing me everytime I turn it on!

Like iv said before iv pulled off some epic slides so far.. No idea how but I have lol.

Another thing.. When I do a nice lap and it feels fast and that I cant go any faster.. I look at the leaderboard and somebody is 8 seconds faster over a lap.. That tells me there is much much more to learn about this bike sim before I can really say this or that isnt right!

[girlracerTracey]

..ratio holds (so if you have a neutral throttle on and a nice two wheel drift, don't expect to be able to add any more throttle unless..

"Two wheel drifts". Now you're talking Allen!

My father reminisced to me about two wheel drifts.. I like what you have to say very much already Allen.

@ Bob: yes I agree with all that you are saying m8.

gpbikes is epic isn't it? Life without gpbikes would be rather dull for me now. A bit like a world where Lamb Dupiaza had never been invented..

I have a huge amount to learn on the "game". A mountain to climb. Climbing that mountain is going to be a memorable and crazily enjoyable journey I think.

Dumbfounded and in awe of what PiBoSo and his team have achieved if I'm honest..

Incredible project gpbbikes. Truly groundbreaking in fact. Don't take up hang gliding or anything similar PiBoSo..for all our sakes! 

grT   

[HornetMaX]

Tracey you should take a look at what Hawk uk is doing with track surfaces, mallory park thread.. I fully understand what you want from gpbikes but at the same time its hard for me to commit to an idea and direction with physics.. Simply because everytime I play gpbikes something different happens.. Eg. When I started playing I couldnt do this and that but now alot of things make sense.. An the physics model is still suprising and impressing me everytime I turn it on!

I can tell you from experience that if I stop playing GPB for 1 month, then it takes me 1 month to get to the same times I was able to do before.
I may be slow and old, but it gives an idea.

MaX.

[EdouardB]

As someone who raced 2/350 machines in the 80s (TZs and Rotax 256 engined) I can say without any doubt it is a lot easier to feel yourself sliding a bike on the exit of a corner than to see another rider doing it in front of you

I totally agree. But I was talking about the "huge" powerslides that most games allow you to do nowadays, not the slight wheel spin, and those are visible when following someone.

Also, I agree about what you said with the 5% spin, I remember an HRC interview saying that the maximum traction is achieved at around 5/10% wheel spin.

My point was just that 2 strokes should be harder to slide than 4 strokes in my opinion.
Of all the bikes I've ridden or still ride on the track (TZ250, TZ350, TZ750, FZR750R 0W01, R6, R1 - yes, I'm a happy man ), I've found it quite easy to have a very slight wheel spin on the R6 compared to, let's say, a TZ350 (where I've only had really short wheel spins).

Allen, I'm curious to know what you think about the 4 strokes/ 2 strokes comparison in that regard.

I'm saying all that because in GP bikes the 4 strokes are easy to powerslide, the 2 strokes are not, but maybe that's a good thing. The amount of powerslide in GP500 is ridiculeous imo.

And yes, some haptic feedback would be great

[HornetMaX]

Also, I agree about what you said with the 5% spin, I remember an HRC interview saying that the maximum traction is achieved at around 5/10% wheel spin.

That's a "layman's terms" condensed explantion, stemming from curves like this one (don't know which tire type this graphs refers to, just as an example):



Once again, the 5% stuff refers to longitudinal slip, not lateral one.

My point was just that 2 strokes should be harder to slide than 4 strokes in my opinion.

I'd say 2 strokes are harder to slide in a controllable manner, but I guess that was what you meant anyway.

I'm saying all that because in GP bikes the 4 strokes are easy to powerslide, the 2 strokes are not, but maybe that's a good thing. The amount of powerslide in GP500 is ridiculeous imo.

I'm gonna marry you 

MaX.