Questions tagged [openmdao]
a Python-based, open-source, multidisciplinary optimization framework with support for analytic derivatives and distributed HPC computing
openmdao
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Assign a threshold on the Jacobian of a Dymos problem
I have a multiphase Dymos problem I am trying to optimise. It is not working so far and I think it is because of my sad looking Jacobian, as seen below. All driver values in the problem are scaled ...
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Run two Dymos problems in tandem
My workflow using Dymos often involves running alot of Dymos optimisations in tandem so I can debug faster (i.e. I can try a bunch of different things at the same time). This has been working until ...
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How to Configure HSL MA86 for Use w/ IPOPT in OpenMDAO
I am currently trying to configure the HSL MA86 linear solver for use with IPOPT in OpenMDAO. I am using a Linux Ubuntu computer. I have extracted both HSL MA86 and IPOPT from tar.gz files and created ...
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Dymos/OpenMDAO phase linkage solution reading error
I am running and investigating the Dymos/OpenMDAO example provided here:
SSTO Earth Launch
It runs fine, with different boundary conditions and parameters.
My goal is to make the trajectory in two ...
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In Dymos, is there a way to add a timeseries output to only a single timeseries when a phase has multiple timeseries output comps?
For example if a second timeseries has been added to create tandem phases, can it be specified that only select timeseries outputs are added to the additional timeseries?
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Is there any way to have tandem phases in dymos that don't share a t_initial and t_duration?
For example if there is one long phase, but some short fast dynamics need to be captured in tandem at the beginning of the phase at a higher level of discretization, but these fast dynamics still ...
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Understanding partial derivative error in Dymos
I've built a dynamics model in Dymos, using Jax to calculate the partial derivatives using auto-differentiation. The code looks something like the following:
import openmdao.api as om
import dymos as ...
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'Output states' in Dymos?
I'm building a model in Dymos/OpenMDAO. There are a few states which are required for calculating the dynamics, and then some which I'd just like to derive and output. For example, say I had a very ...
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Constraints or objectives cannot be impacted by the design variables of the problem
I've been expanding my OpenMDAO script to include a sub-iteration. Basically, I have a propeller whose chord and twist distribution is determined by a cruise condition (with collective angle) where ...
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Trying to do an optimization with 3 variables in openMDAO
I am trying to add a third variable in my problem with np but it seems to not work, like the optimization is failing but the code is working so I don't really know what to do.
I don't know if I should ...
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Access values of design variables while solver is running (OpenMDAO with IPOPT)
I'm trying to do trajectory optimisation in Dymos (a library built atop OpenMDAO), but I'm not getting the convergence properties I'm expecting and I'd like to inspect the intermediate solutions of ...
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create a constraint in OpenMDAO
Welcome to everyone reading this post,
So I am trying to create a constraint using 2 variables of my model but it seems I don't know how to setup this.
I am trying to make sure that np_check is ...
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Dymos: Restoration failure when splitting up ODE into two components
I have been building an optimal control simulation similar to the racecar example from the documentation (https://openmdao.org/dymos/docs/latest/examples/racecar/racecar.html). In my model there is a ...
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Multiples Errors in my optimization code in OpenMDAO
Good afternoon,
So after asking a few question, I am working on an optimization problem with openMDAO and I asked a few questions here about previous mistakes and when I tried something new, a new ...
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Issue regarding an out of range problem in my optimization problem OpenMDAO
In my project, I am trying to optimize the Volume of an airship regarding mission requirements and to do so I have the calculation of the weight through out 2 methods and then I substract one to the ...