i have some problems with tank tracks

[bogdan lupescu]

hello

I am trying to animate a tiger I tank
i manage to create all wheels , and working fine
but when I create the tracks, the tracks are very elastic and tracks goes through the ground not on the ground. I search for some adjustments but it seams that is more complicated than i expected


I put here a link with the animation

http://dl.transfer.ro/preview_05-transf ... e03011.avi
( the link is available until 15 mai)


thanks in advance .

[dainiuxxx]

Hi
Have the same problem, there a work arround (kind of)
In general parameters of crawler extended set, Gravel shake offset value and Gravel roughness to 0. This seems to help slightly, but does not solve this problem.


Hope it helps

[Patrik Martin]

hello

I am trying to animate a tiger I tank
i manage to create all wheels , and working fine
but when I create the tracks, the tracks are very elastic and tracks goes through the ground not on the ground. I search for some adjustments but it seams that is more complicated than i expected


I put here a link with the animation

http://dl.transfer.ro/preview_05-transf ... e03011.avi
( the link is available until 15 mai)


thanks in advance .

Hi bogdan lupescu,

One thing that is very important to make sure to have the boogie wheels and the ground separated with at least the size of the template track.
The picture shows a wired extrawheel that detects the ground, a high-poly boogie wheel and a track thread. So the boogies from CrawlerTracks should be the same size as the high-poly boogie wheel so that there is a gap between the ground and the boogie so that the threads stay above ground. However we know that there is a problem with the Crawler Extended that makes the ground cut trough the wheels if it drives over a small hill.

[YMangolds]

So the boogies from CrawlerTracks should be the same size as the high-poly boogie wheel so that there is a gap between the ground and the boogie so that the threads stay above ground. However we know that there is a problem with the Crawler Extended that makes the ground cut trough the wheels if it drives over a small hill.

To avoid this make sure that the tracks wheels are smaller then the vehicles wheels by at least 1.25-1.5 the height of your step. This ensures that the track wheels don't punch the steps through the ground since the collision with them has priority over the collision with the ground.

To avoid the hill problem the best way to link track gears to a crawler is to use extra wheels for ALL ground touching boogies. Crawlers wheels should have extra wheels the same size and position as them that's linked to the chassis and the track's gears get linked to these NOT the crawlers wheels. Reason for this is because the crawlers wheels will ALWAYS touch the ground , even if it went over a very steep hill. By using extra wheels to control the track gears you can limit the amount that the extra wheels can move vertically so when the tank goes over a drastic terrain change the extra wheel will come off the ground like it would realistically. I think I remember seeing one of Luigi's videos illustrates this.

Other things you need to check for is that the normals of the ground are facing up (having the grounds history and transforms frozen is always good to make things run smoother also), and the scale of the main wheel should be established by scaling the top frame object (looks like the wireframe of a red cube) and NOT the wheel. Support wheels can be scaled to your hearts content though.

Another tip when dealing with tracks is that you'll get the best starting results if the vehicle is close to the ground when animation first starts and tracks are created (but make sure it's not penetrating it. If the vehicle starts high above the ground it snaps down to it on the first frame and different parts snap down at different times which can cause alot of problems.

To make the tracks less bouncy you'll need to adjust the configuration for them. Start with Flaccidity Reduction and increase that. For realistic track behavior don't increase it too much. I'd say find out what value they become really stiff at is, then set it to about 75% of that. Then lower gravity until the tracks droop to a believable amount when the vehicle is stationary. If it's still rubbery then increase bending and displacement damping and as a last resort increase the subframes in flaccidity (this will work well but will also drastically increase calculation time so it should be used if all else fails).

[YMangolds]

Also, if the vehicle is moving at high speeds you'll need to increase the number of subframes to be able to deal with the rapid changes of terrain beneath the vehicle

[Rob Neal]

I am having similar track problems. It would be really useful if either craft or it's users could provide some simple demo scenario files of finished rigged vehicles so they can be examined. It's not so much a problem with cars etc but the crawler / track simulation is by far the most complex, and if you get anything out of place, it all falls to bits.

Can anyone spare a tank simulation in MAX?

Thanks,
Rob