Belt transmission

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MaartenHo
Posts: 19
Joined: 11 Mar 2019, 14:25

Belt transmission

Post by MaartenHo » 11 Mar 2019, 14:34

Is it possible to simulate a belt that hold something up?
It's supposed to that I can lift a block that is to the belt.

coppelia
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Posts: 7124
Joined: 14 Dec 2012, 00:25

Re: Belt transmission

Post by coppelia » 13 Mar 2019, 13:59

Like conveyor belts for instance?

Have a look in the model library: Models/equipment/conveyor belts

Cheers

MaartenHo
Posts: 19
Joined: 11 Mar 2019, 14:25

Re: Belt transmission

Post by MaartenHo » 14 Mar 2019, 09:07

Not like conveyors, it's more like a belt that rolls up around a wheel while it lifts something. It's like something in picture 1, where the belt can roll up like that.
And another transmission is like something in picture 2, how can I relate the two wheels or how can I simulate such a transmission? The little wheel is placed on a motor

Picture 1:
Image

Picture 2:
Image

coppelia
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Re: Belt transmission

Post by coppelia » 14 Mar 2019, 09:18

You cannot directly simulate the belt, but you can simulate the interaction between wheel1 and wheel2, by linking their joints via an offset and a multiplication factor (only with the Vortex engine). Check for the joint the engine specific properties, Joint dependency (in Vortex properties).

Have a look at the example scene gearMechanism (gears are simulated, but the idea is exactly the same)

Cheers

MaartenHo
Posts: 19
Joined: 11 Mar 2019, 14:25

Re: Belt transmission

Post by MaartenHo » 14 Mar 2019, 09:26

So it won't work with Bullet, ODE or Newton?

coppelia
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Posts: 7124
Joined: 14 Dec 2012, 00:25

Re: Belt transmission

Post by coppelia » 14 Mar 2019, 09:43

It won't work with Bullet, ODE or Newton. Unless you are only interessted to reproduce the movement of wheel1 on wheel2 (via a specific transformation, i.e. offset and multiplication). In that case you can have the joint of wheel2 in position control mode, and inside of a joint callback function you can read the current angular position of wheel1 and apply it as desired position to that joint.

Cheers

MaartenHo
Posts: 19
Joined: 11 Mar 2019, 14:25

Re: Belt transmission

Post by MaartenHo » 14 Mar 2019, 10:00

It's okay, I downloaded the vortex engine!

Now it's possible to simulate the interaction between the 2 wheels? And simulate for example the stifness of the belt?
Which joints do I have to use to relate the two wheels?

coppelia
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Posts: 7124
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Re: Belt transmission

Post by coppelia » 15 Mar 2019, 16:34

You cannot simulate the belt itself. Neither its stiffness. Just the link between two joints. E.g. set the two joints into force/torque mode, and link one to the other via the mentioned setting for Vortex.

Cheers

MaartenHo
Posts: 19
Joined: 11 Mar 2019, 14:25

Re: Belt transmission

Post by MaartenHo » 21 Mar 2019, 09:11

How can I link one to the other? I don't really understand that part... Now I linked one to the other by setting the the other joint to 'Dependent mode' and selected to which joint it must be linked.

Is that the correct way, or do you have to do it another way?

coppelia
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Posts: 7124
Joined: 14 Dec 2012, 00:25

Re: Belt transmission

Post by coppelia » 22 Mar 2019, 14:05

This is not the dynamic way. This way is only used with passive joints, or joints involved in inverse kinematics (unidirectional dependency, passive).
But you want the dynamic way, where the two joints are dynamically enabled and dependent on each other (bidirectional dependency, dynamic). For that, you can only use the Vortex engine. In the Vortex engine properties, you can link one joint to another.

Cheers

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