If you’ve played with Grasshopper then you know how much fun it can be to throw the sliders back and forth and watch your geometry change. What if you wanted to get analysis data for everyone of those iterations? Parametric modeling eases the task of generating multiple iterations, but it can be a bit laborious to feed everyone of those iterations to a simulation analysis software. Instead of stepping through the same set of steps for each iteration its helpful to shorten or automate the process required to achieve feedback.
This is one of our first explorations into creating connections between Grasshopper and other simulation analysis software, specifically the structural analysis software ANSYS. This connection is being created through the use of four vb script components which are responsible for writing the ANSYS macro, exporting IGES files, creating the ANSYS input file, and retrieving the ANSYS output file.
Once the ON button is set, it takes about 5 seconds for the analysis results to appear in Grasshopper. The output file contains results for each analysis that was specified within the ANSYS macro. In the following example of a space frame structure, the element axial stresses and the node displacements were analyzed and the results were then used to color the Grasshopper geometry as well as displace the nodes. It is then possible to take advantage of the rendering tools within Rhino to create more compelling graphics than the ANSYS vector graphics. Another, more powerful possibility is to use the ANSYS results to begin to size members in response analysis results such as the diameter of a pipe. In the below image, members experiencing compression forces are blue and tension forces are red. The diameter of the pipe also increases in response to the intensity of forces.
This is just the first step in a series of explorations that will attempt to create more direct connections between parametric modeling and simulation analysis. By no means is this approach a replacement for the knowledge that consultants bring to the table, but instead is seen as helping to facilitate better collaboration.