OpenSEES - MatLAB interface

[giuseppe.abbiati]

Is it possible to resume a time-history analysis at a certain time after closing OpenSEES?

I would like to send a displacement command to OpenSEES from MatLAB and retrieve a restoring force from OpenSEES.

I tried with OpenFRESCO but also for linear model with about 20 DoFs the convergence fails after 100 iterations.


Many tanks

Giuseppe

[fmk]

1. possibly, look at the database command. it does not work for all elements and materials.

2. yes. open a socket, say s and just do puts $s whatever and gets $s whatever

3. there should be no convergence problems with OpenFresco as you are supposed to choose an integration scheme that converges in a known number of steps (typically 1) and choose the appropriate test. suggest you look again at what it is you are up to.

[geyas]

Newest: I have solved the problem. "model BasicBuilder -ndm 2 -ndf 3" should also be put in "analysis-2.tcl"

Old Message:
Hi Giuseppe,

If your problem had been solved, can I ask you how you solve it?

What I'm trying to do is :
1. Use OpenSEES to analyze one step of a dynamic analysis, use database command "save 1". (Filename:analysis-1.tcl);
2. Close OpenSEES;
3. Retrieve the restoring force, and calculate the command(d,v,a) of the next step ;
4. Build a new tcl file (Filename:analysis-2.tcl), use database command "restore 1" at the beginning, use command "pattern" to construct the new command(d,v,a)
5. Use OpenSEES to run "analysis-2.tcl"

I can run "analysis-1.tcl" successfully. But when I run "analysis-2.tcl" , the error comes to be " invalid command name "pattern" while executing..."
When I merger "analysis-1.tcl" and "analysis-2.tcl" to a single file ("analysis-12.tcl"), and just run "analysis-12.tcl", it successes.

I'm so confused. When we use database command, cann't we close opensees and then restore the database in a different ".tcl" ?

Thanks a lot!

Geyas

[giuseppe.abbiati]

Dear Geyas,
sorry for the great delay in the reply but then I paused my OpenSEES activities.
Finally I solved by running a complete OpenSEES analysis from Matlab via 'dos' command (see matlab ref.).
I removed recorder before exit from OpenSEES.
As a result, time history were available for Matlab.
Could you please send me both script if it is stiil of your interest?

Many thanks
Giuseppe

[giuseppe.abbiati]

PS giuseppe.abbiati@gmail.com