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Hey.

I have been going over the parameters of Bimota Tesi (from Volty) and for the love of pie I can’t understand its leaning action... The knack doesn’t seem to be in the parameters.txt at all...

But the point is: I have been thinking of a good idea for an original vehicle – Unibike. The best description would be a cross between the Tesi and a segway, motorised and cool. Meaning that it would lean correctly like Tesi does, and would actually nod forwards when accelerating and backwards when braking. It would probably need some strategically placed additional invisible wheels and clever spring tricks for the backwards and forwards nodding, though.

I thought it would be relatively easy to do, if the leaning system of the Tesi depended on crossed-up springs or something, but I don’t see the knack just by looking at the parameters...

So, if anybody can help me clear things up, then I would be very grateful. I don’t want this idea to be wasted.

And I thought MOH would be the best person to make a good body for the Unibike as well, seeing that his work is high-quality and my knowledge of the graphical side of car-making is null

But anyone’s help is welcome!

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Citywalker

hey dude. ive also gotten the leaning effect to work. basically its all in the COM. i am no 3d modeller but i can help with some param features. my email is zipperrulez@gmail.com.
edit:
lol i lost the bike i did a while back, but you can see it in this video:
http://www.youtube.com/watch?v=bjVh8mhJBmQ

Yep, I think the trick is to have only 2 wheels, and to set the CoM (centre of mass) quite below the vehicle. Of course it would be physically impossible in reality, but it will make the vehicle leaning like a bike.

Correct. The CoM of the Tesi is placed really low to make the bike lean in the corners. That also causes the bug on lego tracks, because the CoM is hanging under the track zones and this gives a continuous reposition loop.

You also have to edit the AngRes or ResMod value (one of them, i dont remember which one), to prevent wobbling after steering in.

I think you can make a working segway if you toy around with those two values.. finding the right balance takes some time.

ive made a honda cbr bike, which hasnt been released yet, and when making it i found that putting the com lower than the bike made it lean, and also, under acceleration leant forwards, and under braking leant back.

so this is exactly how i pictured the motion you might want for this unibike

ill happily make a model for it but i have no clue as to what it should look like haha

heres a little vid of the way the cbr with an "innapropriate" rider rides
http://www.youtube.com/watch?v=2MNuGm1AffY

Okay, this is exactly what I wanted, yes. But there's a problem.

After much thinking and tinkering with the Tesi, I have found that it’s not possible to do directly – Re-Volt’s physics won’t allow it, just like the real world physics won’t allow it. So, some clever trick would be needed. But all the tricks I have thought about have hit walls with the limitations of the Re-volt physics system. I can’t put one wheel turning left, one wheel turning right and one wheel not turning at all, because two front or two rear wheels will always turn together, regardless of parameter settings. I can’t put just two opposite-turning wheels near each other, because when the Unibike leans forward, it still lifts the rear wheel off the ground, even if it’s very close to the front wheel, and thus all steering stops. I can’t put two differently powered wheels beside each other, because their power-difference can’t be controlled dynamically. I can’t put it on two invisible opposite-turning wheels with very soft suspension (front and rear), because then I can’t have a visible wheel with skidmarks in the middle, as it would steer along with the invisible wheels and affect the steering.

Still, the last idea could work, sort of – I could put a front wheel as the visible centre wheel and it would at least turn in the right direction, but now I can’t get the suspension thing to work out with grip. Somehow all wheels lose all grip when I change the spring settings (stiffness, damping and restitution). Something’s fishy and I don’t know what...

Oh, and an idea of a model: http://jmuafvlab.wordpress.com/2008/09/ ... motorbike/

have you ever driven this car?

http://rvzt.zackattackgames.com/main/co ... tone+Wheel

its only one wheel, and the concept of it (i think) is similar to yours, only i dont think this one leans

Yes, I have seen it, and it uses two wheels as well. And it doesn’t lean only because the CoM value (centre of mass) has (accidentally?) a positive value. Made it negative and it started leaning. But! – it doesn’t nod forward and backward (can be verified with cockpit camera), obviously because it has the same rock-hard springs as Tesi (actually, there’s much evidence of Tesi being the basis of its parameters everywhere...).

Well, it actually nods backward a little when braking hard, but then the front wheel lifts off the ground and, again, all steering stops.

Can someone knowledgeable get e.g. Tesi and actually give it enough springs to nod on two wheels? This would be a base to build on, at least. I don't seem to get even this working properly

if you lower the centre of mass below the car, to make it lean, it also flips it in the x axis so under acceleration the front will dip. this is why tesi has hard suspension. I found this with my cbr, and has to put the stiffness to 3000, so i imagine it would be easy to achieve, however it means under acceleration out of corners makes the wheels lift off the floor and makes the car spin out.

Ill have a mess around with some parameters and see what happens, then ill do a post

So, it’s done. It works, leans, nods, steers and looks generally awesome . Well, apart from the last part :/ I’m very much graphically challenged, meaning I have zero knowledge about the graphics part of making a car, so please, anyone interested, make this puppy have a reallllly cool look.

You can do whatever visuals you want, as long as it still stands on that one wheel and has vertical springs for that wheel. Oh, and it’s electric, so no exhaust pipes, obviously. Other than that - run wild with it. (But don’t change the parameters, they’re a bit tricky to balance, though if you make a larger wheel, the bike will definitely need to be tweaked again. On the other hand, a larger wheel might look good...).

You’ll get credited, naturally <smiles>

The Unibike is there:
http://www.upload.ee/files/576243/worki ... e.zip.html
Try it with the cockpit camera

I could try... xD
PS: I like the yellow texture set very much... way better than the red one
PPS: I'm burner94, on RVZT and ReVolt Live