Modelling Foucault's pendulum attached to a cylindrical disk in Simscape Multibody

8 visualizzazioni (ultimi 30 giorni)
Hi,
I am trying to model a spinning disk attached to a rod in simscape multibody, as shown in the diagram attached. The disk is supposed to spin at a constant rate and cause the pendulum trajectory to shift, as opposed to going back and forth. The rod does not spin on its own axis. Please see this https://www.youtube.com/watch?v=pKGgICawAKc as an example of what I am trying to model, but note that I have a spinning disk instead of a spinning sphere.
I have also attached a draft of the model, but it doesn't seem to work correctly since I cannot see the pendulum behaviour and both the rod and disk are spinning along the vertical axis. Could you please help introduce correct translational behaviour into the system or share any similar models you may have done?
Thank you for your help.

Risposte (1)

Steve Miller
Steve Miller il 10 Gen 2022
Hi Jake - attached to this answer is a model I built that I believe models the system you describe. Please note the location of the sensor and the frame used to define the camera. They are both in the reference frame that is spinning.
--Steve
  8 Commenti
Steve Miller
Steve Miller il 20 Gen 2022
The tip of the pendulum has to follow an arc. If you want to specify the linear speed of the tip of the pendulum, you need to figure out how fast the pendulum needs to be rotating about its two DOFs to achieve that linear speed (which must be within a plane normal to the pendulum rod) and set the rotational speeds there. The calculation is trivial if the pendulum is pointing straight down, slightly more complex if it starts at an initial angle.
Jake Barlow
Jake Barlow il 20 Gen 2022
Modificato: Jake Barlow il 20 Gen 2022
Hi Steve, thank you very much for your replies. So for very small initial angles, am I correct in suggesting that the linear speed in the horizontal plane can be taken to be the resultant of the rotational speeds in the x and y directions?
If I want to make comparisons with a simple pendulum trajectory, that is, no spinning disk or rod, then it will be difficult to set the simscape initial velocities in rad/s or deg/s or rpm since a pendulum 2D system moves in a plane with no rotations along its vertical axis and angular momentum is not conserved due to gravity.

Accedi per commentare.

Prodotti


Release

R2021b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by