Tank wheels are shaking over tracks

Help and Feedback Scripting Support
#1

im trying to fix suspension on this tank but the wheels keep shaking nonstop causing lots of problems with the movement

video:

each track is connected at a hinge constraint
each wheel uses two springs with one prismatic constraint

limits:

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image226×549 100 KB

free length (front three wheels {big wheels})
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(5 free length)

free length (back two wheels {big wheels})
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(6.2 free length)

tracks connected through a hinge constraint connected to the front wheel, and another part connected to one track piece and those two connected with a prismatic constraint

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image804×480 143 KB

red = connectors
yellow = track piece

spring values
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i tried changing the values of this nothing changed it

2 Likes
#2

On first glance it seems a cancollide issue.

Or maybe two constraints fighting each other.

Does the tank move forward?

1 Like
#3

Isolate the issue a bit… make tracks noncollide and see if wheels work well with the springs.

1 Like
#4

the tank moves fine forward, its glitching out when turning
i turn by speeding up one track and slowing down another

#5

wheels are fine by themself no bouncing at all

#6

So you feel it might be the tracks?

Do the smaller wheels rotate faster than the big ones?

#7

all of the wheels turn at the same rate

#8

Has this worked for you before? I have never worked with tanks but i would assume smaller wheels need to rotate faster than big ones to keep up with the same distance covered.

#9

it was working before but with a different model the springs were set up the same though

#10

nothing is wrong with the movement its just the wheels will shake while on top of the tracks. like in the video you saw the tracks moving up and down very fast sometimes going into the ground

#11

Have you tried increasing the restitution on the hinges between the tracks? Let it give a little so that they arent as harsh against each other…maybe will soften the movement.

#12

the hinges dont have any limits

1 Like
#13

One more idea…it might be the ratio of how much slower the other side rotates when making a turn… maybe try a slightly different speed for turns and see if improves or worsens? Adjust accordingly

#14

im not turning at all… the wheels are just shaking without movement

1 Like
#15

I see… sorry im trying to think of what else it could be. At this point, and im sure uve done this, would be to go one by one thru the constraints and make sure none have anything enabled or ticked that shouldnt. Since u did this before on another model u know that even one constraint acting incorrectly will make your whole tank jitter.

1 Like
#16

i looked through everything about 20 times i have no idea what is wrong with it

1 Like
#17

after messing around with spring limits and the restitution i got it to not shake over the tracks but another problem rose

its not smoothly turning now
focus on the moving green line around the tracks

they are meant to move around the tracks without stopping at all
do you got any idea why this is happening

#18

maybe try lowering the friction of the wheels or raising it.

Try making the wheels massless.
Try making the tracks massless or more dense.

Do you speed the tracks up to match the wheel speed when turning?

#19

i think that might be a physics issue. Instead why dont you try making the tracks spin in opposite directions when turning? I think thats how they work irl.

#20

the tracks are connected to the front wheel which turns at the same speed as the rest of the wheels