animating tank tracks... how?

what would be the easiest and fastest way to get tank tracks to move with the rotation of wheels? its for this

https://blenderartists.org/forum/viewtopic.php?t=21819&start=15

do a search for tank tracks. there are multiple threads on this already. :wink:

i couldn’t find any. how many pages is in down the list?

No clue,…just use the ‘search’ function.

i did use the search. i went like 15 pages down the list and couldn’t find anything about tank tracks. i found some tanks but none being animated.

Remeber to click on ‘search for all terms’ rather than ‘search for any’. makes a big difference. I did a search for ‘tank tracks’ and found a link to a tut almost immediately,…I’m not trying to be a jerk,…just trying to get people to use the available tools.

there was a tutorial on the old www.blender.nl site, i think there’s an achive of them somewhere

There is not a SIMPLE solution, look for the tutorial in the tutorial list.

In a nutshell, you must make a track link, parent to a curve describing the track profile and make the link follow the path.

Then you must duplicate BOTH and add a time offset so that the duplicate link follow the first as if they were really connected.

Then you must go on duplicating untill you have the whole track. It is long, tiresome, and prone to errors (If the last link does not match the first…

Have a look at a movie of mine

http://reblended.com/www/s68/movies/gears.avi

Stefano

I feel like such a scrooge. :stuck_out_tongue:
<edit> I just thought of an easy way to do it too,…I will test this out momentarily,…:
Just make a bezier curve,…extrude it a few times, and wrap it like a ball of yarn where you want your treads to go,…change path length to some figure, oh, say 800,…wrap the curve say 8 times, and,…
make a tread, duplicate it,…set an offset,…duplicate it,…set an offset, etc. So, they will be all piled up at frame 1 and frame 800, but in between, you have over 700 frames of good tank action,…I will try this out brb…

yep it works. here’s my test .blend.
http://home.att.net/~zolgnar/tanktracksexp.blend

Are you sure it is easier?

Stefano

No actually, I only vaguely remember reading the other method, but it struck me as complicated at the time. Perhaps I should go back and read the tutorial… [!]
Oh man, I just read your method,…it leaves my brain feeling all jelly-like,…totally lost,…

Here is a short tut how it should work.

1.) A single shaped bezier circle as track follow curve.
2.) A single track link as child of the follow curve (curve path and curve follow set in Edit buttons of the curve)
3.) Place the track link at the start point of the curve.
4.) Duplicate (Shift+D) the link and give it a negative time offset (Object buttons (F7) of the track link).
5.) Adjust the time offset and the width of the link so that the two links are next to each other.
6.) Repeat step 4. several times to get a complete track. (Finally you may have to adjust the width of the link a bit.)
7.) Give the follow curve a speed Ipo set to cyclic extrapolation and insert key frames at x=0, y=0 and x=100 and y=1. This gives a rotation cycle for the track. (if path lenght is different from 100 you have to set corresponding values for the second key)
That’s it for the track.

Making the track movable and synchronized with wheels.

8.) Create a single armature bone.
9.) Make the bone parent of the follow curve (use bone) (you shouldn’t use loc,rot ipos for the bone and track !!!)
10.) Add the wheels and synchronize their rotation with the track with a rotation Ipo (set to extend mode).
11.) Make the wheels childs of the bone.
12.) Create a curve that your track should follow (“rail curve”).
13.) Make the bone child of this path.
14.) Synchronize the track rotation and movement with the path length of the rail curve.

That’s it for a movable track.

To get acceleration and deceleration you would have to play with the speed ipos.

Here is a sample .blend
Http://www.molblend.gmxhome.de/tanktracks.blend

Hope this helps.