Help with Setting Up Random Vibration Analysis in Creo Simulate 10.0 (CubeSat Modal/Random Case)

[EP_13234518]

Hi everyone,

I’m working on a Random Vibration Analysis in Creo Simulate for a 6U-XL CubeSat structure, which is mounted inside a deployer and tested on a shaker table.

So far, I’ve successfully completed the Modal Analysis:

- I constrained the side rails (interfaces with deployer).

- Assigned material to the structure.

- Used point masses for each unit to replicate the payloads, and added weighted links to distribute the masses.

- Element mesh was created using AutoGEM (solid)

Now, I’m moving to the Random Vibration (PSD) Analysis and have a few questions I hope someone can help with:
- I’m applying an enforced motion (base excitation) on the constrained rail surfaces, simulating the shaker input. Is this the right approach for replicating a vibration test inside a deployer?
- I used weighted links to connect the point masses to the payload mounting holes. The holes are not constrained (only the rails are). Is that correct, or should the payload attachment holes be constrained too?
- For the PSD table, should I use linear or logarithmic frequency spacing? The vibration profile is based on a launcher-provided spec. Where should I insert the values to get the results? (I pressed on f(x) under PSD and created my table with the launcher values. Is this the correct way?)
- Any other best practices I should consider to obtain valid results?

Unfortunately, I can’t share the actual files, but I’m happy to describe my setup further or provide screenshots of the model and settings if needed. I would really appreciate some step-by-step guidance on how to properly fill in the required inputs when creating the Random Vibration study in Creo.

Thank you in advance for your time and support!

[Catalina]

Hi @EP_13234518 

Thank you for your question. 

Your post appears well documented but has not yet received any response. I am replying to raise awareness. Hopefully, another community member will be able to help.

Also, feel free to add any additional information you think might be relevant. For example:

• Is applying enforced motion (base excitation) on the constrained rail surfaces the correct approach for replicating a vibration test inside a deployer?
• Should the payload attachment holes be constrained, or is it correct to only constrain the rails?
• Where should you insert the values to get the results? Is pressing on f(x) under PSD and creating the table with the launcher values the correct way?

Best regards,