Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

How to determine the kinematic constrains?

How to determine the kinematic constrains?

How to determine the kinematic constrains?

Hello Community,
i need help in defining the connection between x3 and x1 (kinematic constraints). My Professor can´t explain it well, im confused. Is there a scheme on how to determine the kinematic constrains?

A homogeneous cylindrical pulley (mass m1, radius r1) has a rope S1, which is connected to the surrounding area via a spring (stiffness c)

The disk rolls on the horizontal
plane. The center point of the cylinder is connected to block 3 (mass m3)via a second, rigid rope S2

The rope S2 is guided via a massless deflection pulley 2
(radius r2), on whose bearing the constant frictional torque
MR acts on the bearing

In the sketch, the spring is relaxed and the
system is released from rest

Determine the speed v3 of the block 3 as a function of its deflection x3 from its rest position.

Given: m1, m3, g, r1, r2, c, MR.

RE: How to determine the kinematic constrains?

As a starting (finishing?) point I'd start with the final static position ... everything stationary. I think the tension in S2 is the weight of m3. I'm not sure about the load in spring S1 ... for moment equilibrium it should be S2/2, but the Fx force equilibrium it should be equal to S2 (but then the moments don't balance).

Look at the dynamics of each part, in isolation ... m3 is only moving up/down, with some dynamic acceleration. The spring, S1, can only extend. The wheel, 1, translates and rotates.

What simpler problems have you solved ?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close