FEA on Soft Structures

[zaryab94]

Hi Peeps,

I am currently working on Soft Robotics at Texas A&M. I want to get some information about a problem in my research.
Which is the best software to do FEA on elastomeric materials ?

Regards,
Zaryab Shahid

[XYZAidan]

Hi,

I do not have much experience with FEA, but many researchers use Simulia from Dassault Systèmes. The Soft Robotics Toolkit has quite a bit of documentation regarding the modeling of soft robots with FEA. Here's an example: http://softroboticstoolkit.com/book/pneunets-modeling
I hope this was helpful. The scientists of Super-Releaser may have some input on this. I'll send this thread to them.

[Gianteye]

Hi Z,
I haven't played with too much soft robotics FEA. Solidworks has a FEA package that can do some basic elastomer FEA if you're looking specifically at deformation, flow, or heat, but won't be too much help if you're looking to generate pneumatic or hydraulic soft mechanisms. As Aidan said, the Soft Robotics Toolkit talks about some simulation software (such as Abaqus for evaluating the PneuNets actuator) but I've never used the software, myself.

It's an area I'd love to know more about. Currently the research seems pretty thin on methods to model and evaluate compliant mechanisms. Please let me know if you identify promising software.

Cheers,
Matt

[zaryab94]

Okay ! There is limitation on the modelling the elastomer when they have large deformations. Currently, I am working on it. I will let you know.

[ugabuga]

Hi Zaryab,

I am also working on soft robotics here at Rutgers University in NJ. I am following the instructions on the SoftRobotics toolkit in order to do FEA analysis using Abaqus. I am currently working with the PneuNet actuator.

Despite following all the instructions to the dot, the job ends with an error. I have spent hours and hours trying to resolve the problem but apparently for some reason the model doesn't converge mathematically.

I also noticed that if I disable inter-chamber interaction (modeling what happens when pneunet chambers swell to the point that they start touching each other, which is the big benefit of the fast actuating pneu net actuator), then the job runs and I see the deformed actuator as simulated by the software, however the adjacent chambers go through each other, so the model isn't really correct.

I hope this is useful to you if you decide to use Abaqus. I downloaded their example as well and ran it as is and still got the same errors. I even tried a different version of Abaqus. So modeling soft robots won't be easy if there is self-contact.

By the way if anyone has any info on how to get in touch with the people who put together the soft robotics toolkit, so I can ask for assistance, that would be great. Their forum isn't active. Ghost town, which is a shame. This seems like such a promising area.

Good luck,
Chris

[Gianteye]

This is useful info to know! Thank you.

I'm not sure how to get in touch with the SR toolkit folks, but I know some people who might. Let me see if I can drum anything up.

[ugabuga]

Thank you. If you could indeed put me in touch with someone I would be eternally thankful. I've wasted days on this

[XYZAidan]

Thank you. If you could indeed put me in touch with someone I would be eternally thankful. I've wasted days on this

Hi Chris,

Have you made any progress on your simulation? I may be able to put you in contact with someone at the Soft Robotics Toolkit (like Matt had said).

[ugabuga]

Hi Aidan,

Unfortunately I haven't gotten any further, so if you could indeed put me in touch with someone that would be a great help!

Thanks in advance

[XYZAidan]

Chris,

Sorry for the late reply, I've been looking into my possible resources on the subject. Besides your earlier post, is there anything else to note regarding the problems you are experiencing? Let me know.

Thanks,
Aidan