SQP-Hopper-tutorial case blowing up

[basud0817]

Hello,

I am trying to run the SQP-Hopper-tutorial case, and it is blowing up. I am attaching the zipped report file and screenshot of the error. Kindly help and let me know where I am doing wrong. I need to run this case.

I did not change any set up and using the same set up as in the tutorial.

I look forward to hearing from you.

Thanks and Best Regards,

Sincerely,

Debashis

hopper-sqp_2026-02-19T103103.454628.zip (4.1 MB)

[basud0817]

hopper-sqp_2026-02-19T155734.437084.zip (9.0 MB)

Hello, I was able to make it run. But in the attached report file, one case the particles went out of the hopper domain. Not sure. The attached zipped file has everything related to the case. Need some help why is this happening. Changed the SQP parameters and this happened.

Looking forward to hearing from you.

Thanks and Regards,

Debashis

[jeff.dietiker]

Did you use the superquadric designer when you changed the particle shape? If you didn’t, you also need to recompute the diameter (this is the bounding sphere diameter), which is not straight forward. It is better to use the superquadric designer to make sure all inputs are consistent.

[cgw]

I wonder if there’s something we can do in the GUI to prevent this - like if the user edits the shape parameters without using the designer popup, we could recompute the bounding diameter automatically. Actually I think having the bounding diameter be a user input is not a great idea, generally users should use the correct (computed) diameter. For collision detection, sometimes we need to override the diamater, but perhaps this would better be specified as a factor applied to the computed diameter. That would not cause trouble if the shape parameters changed.

[basud0817]

Dr. Dietiker,

I think I am using the Superqudratic Designer.

I will let you know how this works.

Thanks and Best Regards,

Debashis

[basud0817]