MATLAB Answers

Modelling Wave Forces on a Buoy

2 views (last 30 days)
Ben Hauben
Ben Hauben on 10 Jun 2021
Commented: Ben Hauben on 15 Jun 2021
Hi all,
I'm still very, very new to the Simulink/Simscape side of the MATLAB/Mathworks suite. I have been trying for the last few hours to find a method of converting the heave wave forces on a buoy into a functional method for finding its position at a certain time. Effectively, this involves an external force of oscillating magnitude acting as given by the attached function. Despite my best efforts, however, my system appears to create a constant upwards load (which is greatly overshadowed by the force of gravity. Am I missing something? Please let me know.
  4 Comments
Ben Hauben
Ben Hauben on 14 Jun 2021
Oops, fixed it. Not looking like I'll get a reply for it but you know it happens

Sign in to comment.

Accepted Answer

Yifeng Tang
Yifeng Tang on 14 Jun 2021
Thanks for sharing the model.
Looks like the main issue is caused by the source term inside the Heave Wave Force Signal. It was set as a "repeating sequence stair", so it stays as a constant for a duration of 5*T you set, and then move on to the next value of the function. For the 60 sec you simulated, the output from this source remains constant until the last step, when 5*T=60. If you run the model for longer, you will see the multiple steps, each with the value of one element in the array produced by the HeaveFK function. I don't think this is what you want it to do.
Using the "Repeating Sequence" block instead. See the attached example. And the position is now oscillating.
  1 Comment
Ben Hauben
Ben Hauben on 15 Jun 2021
Thanks so much! This makes life so much easier.

Sign in to comment.

More Answers (0)

Products


Release

R2020a

Community Treasure Hunt

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

Start Hunting!