Subassembly Composer Series: Part 1: The Flowchart

As you should all know from Joshua Modglin’s post the other day, the Autodesk Labs have released the Autodesk Subassembly Composer (hereafter referred to as SAC because I like abbreviations). It’s still in beta form but there is some nice features hidden behind its innocent user interface.

I’m going to make some assumptions here. First I am going to assume 1) you have already read Joshua’s post and 2) you were so excited you already downloaded it to your machine. I’ll wait here while you take care of that…

clip_image002Now that we are all caught up let’s jump into the logic that the general user needs to grasp in order to make something fun. The logic in SAC is all flowchart based. The program chugs along the path starting at the appropriately names “Start” box, following the arrows, and when it gets to a conditional box it makes a decision and then continues its way chugging along to create an output. (We are talking about fast chugging here!)

Yesterday I made my first flowchart and I learned some things along the way. I wanted my first flowchart to be exciting enough that it would teach me something but simple enough that I would learn something. I’m going to break this post into a multi-part series because I think there is plenty of things to keep us discussing for at least 4 or 5 parts. So let’s first talk about the flowchart setup.

First I started plopping on points and links, after all, I had already read Joshua’s post and felt pretty confident that I know that I had to put two points before I could connect them with a link. So I jumped right in and started throwing together some points and links into the SAC Flowchart window.

Then I realized the problem with this, what if I want to add in something above point P3? Well you have clip_image002[4]two options, 1) you can throw it over to the side and connect in and then connect back or 2) you can shift everything down manually one by one (I can’t wait until the lovely programmers make it so you can select more than one at a time!). The OCD user in me needs everything nice and neat and lined up, so I tend to go with option 2. That’s when I discovered Sequences. Sequences make me happy, everything gets tidied up in a nice neat package all its own. And even better, if you want to add in an extra point or link it shifts everything down for you. Snazzy! So I did the next few pieces of my assembly in two separate sequences. Over there at the right is one of the sequences all expanded. The joy of sequences is they make the flowchart a lot less busy. You can use sequences to either take care of pieces of the puzzle (at right I put all the points and links for the portion of my concrete slab that was below grade into a sequence) or you can use the logic that was summarized in one of the latest YouTube videos about SAC I was watching the other day, where she put all her points in a sequence and then all the links in a different sequence to ‘connect the dots’. I can see benefits to doing it either way: Connecting as you go as shown on the right (P5+P6=L5, P6+P7=L6) ,or making all the points and then connecting at the end (P5, P6, P7, and then L5, and L6 later).

So what does it all look like so far? Well here’s the flowchart. If I were to do this again I would put all those points and links on the left under start in their own sequence but I think that this gives a good visual of how the sequences really consolidate things.


And here is the subassembly:


But wait, what is that diamond thing? Conditionals and Decisions! We’ll talk more about those next time. Stay tuned!


  1. Kati Mercier, P.E. says:

    Am I allowed to comment on my own post? I just am so excited I had to share and didn’t want to wait until Part 2 (because it doesn’t really pertain to Part 2, it pertains here), you can nest sequences! How cool is that? I think from now on I am going to make a sequence for each “part” and then within that sequence put a sequence for the points and a sequence for the links. Rename them and you have the ultimate neat and tidy package. No image, just go try it!

  2. […] Subassembly Composer Series: Part 1: The Flowchart […]

  3. […] simple subassembly that is one-size-fits all). But before we dive in, lets make sure that you read Part 1 about putting together the flowchart and Part 2 about setting up and using […]

  4. […] you understand the basics of building a flowchart and using sequences (Part 1) and you’ve got a handle on how to make and use variables (Part 2) and you see the power of the […]