Surface load


I am trying to design a bridge in Robot using Dynamo, I need to define a surface load on the road. I have used structural analysis package, it is very handy but only has UniformMemberLoad.ByBar which only takes bars, not surfaces.

Any help is greatly appreciated.


Hi Tofigh,

Currently we are not supporting surface loads nodes in Dynamo as we had problems with them in the past. We are working on making them available for the next release later this year or in early 2020.

Best Regards,

Hi @Tofigh.Hamidavi

You can code it yourself by using a python script inside dynamo.
Here are some topics that solved this problem.
Creation of load in contour(message 14)

Creation of the panel by python script

Message from Aug 5 calculate model

Be aware that when you use a python script for the loads, the build in node doesn’t work anymore.

@Maciek_Kubica Is it correct that bars and panels/claddings are listed in “the same ID numbers”?
I mean when i create a bar with a python script with number 1, and try to create a cladding also with number 1 i get an error. if i change the cladding to a number that is not in use by bars it works.

If you have more question regarding the code for planar loads let me know.

gr Edward

Hi Edward,

Can you send me both python scripts for testing - one with correct and one with incorrect numbering ?

Hi @Maciek_Kubica

Thanks for your reply.
Here a the files.
Error in the script which is not working.(is by creation of cladding 1)

Script which is not working.(red boxes are where numbers are assigned)

Script which is working. (red boxes are where numbers are assigned)

Cladding_bar_numbers Working.dyn (55.4 KB)
Cladding_bar_numbers not Working.dyn (54.0 KB)

If you have more questions let me know, and i’m curious about what it is.

The versions of the programs i use are:
Robot structural analysis 2020
Dynamo studio core


For my interest: did you check it out?

Hi @1234eddie.
Thank you for your patience and sorry for a tardy response.
Unfortunately we haven’t reviewed the issue with the wrong api id numbering that you reported last year yet.

However, within our planned works we will be reviewing all RSA-Dynamo related problems including yours in the comming weeks.
I’ll speak to you as soon as I have some more detailed info on your issue,


1 Like

Hi @1234eddie,
Sorry for a late response. You can not use the same ID number for a bar and for a panel/cladding becuase in RSA those objects are of the same type, which means bars and panels/claddings have common numbering order.
Additonaly cccording to Robot API:
Each element of the given type has its number suposed to be unique within the same type. This “uniqueness” must be assured by user’'s program.
For this FreeNumber function available by the server of the given type objects can be helpful as it returns the first free user number to be used.
Natalia Łopata