Gear Mechanism

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robzimpulse
Posts: 23
Joined: 16 Feb 2015, 12:00

Gear Mechanism

Post by robzimpulse »

Hi.. i just wondering is there any step to achieve this tutorial video?

https://www.youtube.com/watch?v=mq_b58jUZAU

Thanks.

coppelia
Site Admin
Posts: 10339
Joined: 14 Dec 2012, 00:25

Re: Gear Mechanism

Post by coppelia »

Hello,

first of all, remember that the gear functionality is only supported via the Vortex engine.
Then, have a look at the demo scene Scenes/gearMechanism.ttt.

But basically, all joints that are involved in the same gear mechanism should share a same parent shape. Then, in the Vortex engine properties related to joints, under Joint dependency, you can specify a dependency relation to another joint. By doing so, the two joints will by mechanically and dynamically linked (a torque applied on one will be transmitted to the other one, and vice-versa).

Cheers

robzimpulse
Posts: 23
Joined: 16 Feb 2015, 12:00

Re: Gear Mechanism

Post by robzimpulse »

hi...

i'm already make some scene such as image bellow
Image

i just wonder when i'm running simulation, my gear seems to be glitching and vibrating over and producing a noise in graph.
is this because both of gear i'm running don't move simultaneously or mistake in the design or something else?

here i attach my scene.
https://www.dropbox.com/s/jtkjcs0b00xbk ... a.ttt?dl=0

if something wrong please let me know.

thanks

coppelia
Site Admin
Posts: 10339
Joined: 14 Dec 2012, 00:25

Re: Gear Mechanism

Post by coppelia »

You are not using the Vortex engine, and so you won't be able to link joints together as I described in my previous post.

What you are trying to do - creating gears by having movement transmitted over the gear teeth - is very difficult, will be slow in simulation, and not stable. With any engine. Or it will be very difficult to make stable and operate as you wish.

Use the Vortex engine, or then, fake the link between two joints.

Cheers

robzimpulse
Posts: 23
Joined: 16 Feb 2015, 12:00

Re: Gear Mechanism

Post by robzimpulse »

Hi...

i just want to ask if this mechanism are simulate-able in vrep.
Image Image
and i want to ask how do i purchase vortex for full version simulation because simulating in vrep using vortex keep me getting this dialog.
Image
Image

coppelia
Site Admin
Posts: 10339
Joined: 14 Dec 2012, 00:25

Re: Gear Mechanism

Post by coppelia »

Yes, you can simulate that mechanism. You can do this in various ways:
  • by using the Vortex engine and setting the joint/motor dependencies.
  • easier, by simply actuating the main joint according to the desired movement of the smaller joints (i.e. you know the relationship between the joint velocities/position.
The vortex plugin in distributed by Simwat. Please contact them for details.

Cheers

robzimpulse
Posts: 23
Joined: 16 Feb 2015, 12:00

Re: Gear Mechanism

Post by robzimpulse »

Hi...

in the example before the mechanism works because there is one dependencies in every gear..

just like this mechanism
Image

gear in the left and the right move in the same direction and rotating gear in the center as the result summing the torque of both gear in the left and right.

what i ask is how i made that mechanism in vrep. as i know in vortex dynamic option got only one dependencies setting.

thanks

coppelia
Site Admin
Posts: 10339
Joined: 14 Dec 2012, 00:25

Re: Gear Mechanism

Post by coppelia »

The dependency settings are not reciprocical. In your case, simple have the two external joints point onto the joint in the middle:

leftJoint has under Dependent joint: middleJoint
righJoint has under Dependent joint: middleJoint
middleJoint has under Dependent joint: None

In the exact same way as in the demo scene scenes/gearMechanism.ttt

Cheers

robzimpulse
Posts: 23
Joined: 16 Feb 2015, 12:00

Re: Gear Mechanism

Post by robzimpulse »

coppelia wrote:The dependency settings are not reciprocical. In your case, simple have the two external joints point onto the joint in the middle:

leftJoint has under Dependent joint: middleJoint
righJoint has under Dependent joint: middleJoint
middleJoint has under Dependent joint: None

In the exact same way as in the demo scene scenes/gearMechanism.ttt

Cheers
Hi...
what you instructed is a middle gear is the source of torque in the mechanism. what i want is the gear in the left and right are the source of torque in the mechanism and resulting the middle gear to rotating in the center itself.

here my implementation scene.
Image
what i want to know is there any possible way to make middle gear move with torque as sum of left gear and right gear?

here i attach my scene
https://www.dropbox.com/s/ob7r9hj9pbw74 ... t.ttt?dl=0

if something wrong or bad word come from me, i apologize.

thanks

coppelia
Site Admin
Posts: 10339
Joined: 14 Dec 2012, 00:25

Re: Gear Mechanism

Post by coppelia »

When you define a dependency constraint, it is automatically bidirectional. This way you can link as many gears with each other as needed.

If you want the middle gear to move according to the sum of the left and right gears, simply enable the left and right motors, and disable the middle motor. Your dependency settings are correct, do not change them.

Cheers

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