Thursday, September 9, 2021

Human v. AI Design

My favorite part of having a 3D printer is that I can print my own designs.  I really love designing stuff, printing it, and using my design for its intended purpose.  Recently, I modeled up a pretty basic phone stand.  My design wasn't anything special, I mimicked the designs of phone stands I have seen for sale.

This is my design

As you can see, there isn't anything special about it. After I printed my phone stand, I thought, "I wonder what generative design would come up with?" So I decided to run a study to see what Fusion 360 would do.

I made a copy of my design and trimmed the model down so all I had left were the preserve geometry I wanted.  With this design, I wanted to be able to rest a portable power supply under the phone, so I added a block to the design to represent a portable power supply.  I had to oversize it because I wanted to be able to slide it in from the front.




With my preserves and obstacles modeled, I was able to enter the Generative Design workspace and identify the preserves and obstacles.  The next step was to set up my load cases.  I decided to add one Load Case that represented the phone in the stand.  I figured it would make sense to have a fixed Structural Constraint that held the base to whatever surface it is sitting on.  For my Structural Load, I looked up the specifications for my phone and found that it weighs a half-pound. So I set the load to a half-pound.  From previous experience, I felt that it was likely that Fusion 360 would not be able to solve the study because the load was too light.  However, I decided to start with the actual weight and I could increase the load if necessary.  My suspicions were right and I ended up setting the load to five pounds because the first few attempts to solve the study failed.


When it came to defining the material, Fusion 360 does not have PLA in the Material Library.  For this print, I intended to use a spool of High-Temperature PLA, so I had to do an internet search for the material properties of PLA so I could add it to my Material Library.




The last step is to define the Manufacturing method.  I set mine to Additive and Z+ because that is the XYZ orientation to the print-bed that I intended for this design.  Some day I might run the study again using all orientations just to see what Fusion will come up with.




So here is my phone stand next to the one that Fusion 360 designed (in Fusion 360 then the printed models).






Let's compare key attributes of the two designs to see which one is better. To be fair, I ran FEA Simulations on both of these in Fusion 360, with the same loads and constraints.


Here are my results, listed as my design vs. Generative Designs outcome.


Time to Print: 10 hours v. 8 1/2 hours

Mass: 2.873 oz v. 2.107 oz

Safety Factor: 4.985 v. 4.744

Displacement: 0.1313" v. 0.01845"


In each case, the Generative Design model is better than my design. It can be printed quicker and weighs less. For Safety Factor, if we have a target of 2 or 3, so we don't over-engineer our parts, Generative Designs is better. I included Displacement because my intention is to have enough space below the phone so it can charge it while in the vertical position. Less displacement would mean that I am more likely to be able to fit my charging cord in the phone while in the stand.


I will say that I did make a few edits to the Generative Design model to clear up a few small issues.  First, I should have had an obstacle to represent where the charging cord plugs into the phone and an obstacle representing the phone. Since I overlooked that, Generative Design added some material in the gap where the charging cord is supposed to go. I just removed that material because I knew it wouldn't have any impact on the stand's ability to hold a phone. 



Secondly, I noticed that a portion of the main post extended beyond the base.  I didn't like the way it looked so I edited the model's Free Form feature to clean up that issue. In retrospect, it didn't have a bearing on my ability to print this model and I didn't need to perform this edit.


So this is just a phone stand and may not compare to the complexity of some of the components that you design. However, the ability for Fusion 360's Generative Design to augment my design speaks for itself. In this example, I unintentionally overdesigned a component because I was using standard design techniques. Then with input and direction from me, Fusion 360 improved upon my design. I liked my traditional design, but there was nothing special about it. With Generative Design, I have a more intriguing design that is capable of out-performing my design. I know I titled this blog article about Human v. AI design. Generative Design is a form of AI design, but the process is still driven by the user, and their skills are augmented, and not replaced, by generative design. After this test, I would say that Fusion 360 and I make a really great team. I look forward to other projects where I can leverage this tool to make me a better designer.


A video of this process can be found on YouTube


Monday, August 9, 2021

Generative Design and 3 Axis Milling

 One of my first impressions of Fusion 360's Generative Design outcomes was that the 3 axis milling outputs were too organic and looked nothing like what current manufacturers are producing.  I questioned if the companies I worked with would be willing to adopt the software for that reason.  Recently, I have come to the realization that I was way wrong in my early impression.  Part of the process of defining your manufacturing criteria is that you define the smallest mill you are going to use.  So as long as you create your CNC program with that as your smallest mill, you will be able to manufacture what Generative Design produces.  Creating your toolpaths for a 3 axis milling outcome from Generative Design can be as simple as using Adaptive Clearing to remove most of the stock then using Parallel, Scallop, and/or Morphed Sprial with a Ball Endmill that matches the diameter and length specified in the Generative Design study.

I decided to try creating toolpaths for a Generative Design outcome, using the same mill settings used in the Generative Design study.  I know this feels a little obvious because this is the way the software works.  However, I feel this is necessary to prove my first impression wrong and perhaps give fellow users more confidence in their ability to create these toolpaths.

So I had to find something that would make a good candidate for a Generative Design study.  I thought about a flat screen wall mount, and I remember I had one in a data set I have been using for years.  This design had two arms and a link.  I felt it was best to focus on just one arm.  Looking at the existing geometry, I realized that it already had well-defined preserves and a starting shape that I could leverage.

 


Since I was starting in Inventor, I used "Send To Fusion" to send the model to my Fusion Team project.  From there, I was able to open the model and add a couple bodies that will be identified as obstacles.

Here is a video demonstration of these steps.


My next step was to jump into the Generative Design workspace.  There I was able to identify my obstacles and preserves.  Then, I defined my 3 Axis milling criteria, including which orientations of the model I planned on having setups for, the finishing tool I planned on using, and which materials I was considering.

Here is a video demonstration of these steps.



After the Generative Design study is completed, I was able to explore the models that were created by the study.  In this case, there are two outcomes because the study contained one manufacturing method and two materials.  Fusion 360 will calculate each model's weight, volume, safety factor, and many other properties.  This allows the user to weigh different options and decide on the best model to suit their application.  In my example, I chose the one made out of aluminum because it was lighter and its safety factor was higher.

Here is a video that shows how to explore the outcomes and generate a model from that outcome.  In my workflow, I had a small area that I wanted to clean up.  This video demonstrates that process as well.

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After the model file has been generated and cleaned up, Fusion 360's Manufacturing workspace can be used to create the toolpaths for the CNC program.  For me, the process is going to be to do a couple adaptive clearing operations to get rid of most of the excess material.  Then use operations like Parallel, Scallop, and Morphed Sprial as finishing operations using a ball endmill that matches the parameters I entered in the Generative Design study.  I am not sure what took me this long to realize that is the process.  Perhaps you saw that connection right away.  Once I realized the process, I realized that this wasn't as difficult as I thought and wanted to try it out.  Which was the motivation for this blog post.

Here is a video that demonstrates creating the toolpaths for this part.


The last step in this whole workflow was to send the completed model back to Inventor.  The main point of this blog post was to talk about creating the toolpaths for a part that was created in Generative Design.  However, since I started in Inventor, I feel like I have to end there with the completed design.

Fusion 360 lets users export an IPT from the design files.  In my case, I exported an IPT from the completed arm model.  Then in Inventor, I was able to place the new model in the original assembly.

Here is a video that demonstrates that portion of the workflow.  I also spend a little bit of time comparing the original model to the Generative Design model.


This blog post may have felt obvious.  As I stated before, I wanted to go through this process to help myself feel more confident in my ability to create toolpaths for the models created by Generative Design.  I think what took me the longest to learn was the types of toolpaths that should be used to mill these organic shapes.  Since I have learned some of the best operations to use, I wanted to share that knowledge with fellow users out there and hopefully allow them to feel more confident in their ability to program these models as well.

Friday, July 9, 2021

Inventor AND Fusion 360

Ever since Fusion 360 was introduced, Inventor users have begun asking, "When is Inventor going to be replaced by Fusion 360?"  I will admit, I had the same thought on a few occasions.  The products are so similar that you begin asking yourself, "Why do we have both?"

Autodesk describes Fusion 360 as their next-generation CAD/CAM/CAE software.  With every product we use, someone somewhere is working on the next generation of that product.  I think cell phone companies launch three next-generation cell phones a year.  So it makes sense that Autodesk, and their competitors, would be doing the same thing.  As someone that uses both Inventor and Fusion 360, Fusion 360 feels like what Autodesk would create if they could develop Inventor from scratch knowing what they know now.  

I want to purpose that we need to stop thinking in terms of Inventor OR Fusion 360 and starting thinking Inventor AND Fusion 360.  There are great workflows that support using both tools.  Currently, we can leverage both tools in CAM, Generative Design, and Simulation.  Autodesk has created several different ways to seamlessly connect Inventor and Fusion 360.  If you are using Fusion Teams, you can jump seamlessly between the two products with file associativity.

The latest way to connect the two products is through Inventor 2022's Send to Fusion command.  If you are working with Inventor 2022 and have access to at least one Fusion Teams project, you can push your Inventor model directly to that Fusion Teams project.  It is as simple as pushing a button, once you have picked the Team and Team Project.  From there the file can be placed into a Fusion 360 design file or opened.  Either way, the placed file will remain linked to the uploaded IPT.  If a new version of the file has been uploaded, Fusion will recognize that there is a new version of that IPT and prompt the user to update so they can be using the latest version of that file. 

If you want to see this in action, I have created a video that illustrates the process inside a CAM workflow.


Using Inventor and Fusion 360 gives users greater flexibility in their workflows.  The ability to jump between the products allows users to collaborate even easier, especially if they are collaborating outside company walls.  In my video, I used the example of sending the IPT to a company that is going to program and machine the part for me.  With one button, I was able to send the file, then it only took one more click to send the updated model after I changed the part.  It can't get any easier than that, right?  On the CAM side, the user was alerted that a new version was available.  After they updated, they only had to regenerate the toolpath to reflect the new geometry.

Another benefit is that a seat of Fusion 360 is more affordable than a seat of Inventor.  So if there are users, in your company, that are dedicated to CNC programming or FEA analysis, they don't need a seat of Inventor, they just need a seat of Fusion 360.  Even though I can create the CAM toolpaths with Inventor CAM and do FEA analysis in Inventor, Fusion 360 is capable of those same functions and has a smaller yearly subscription cost.

Fusion 360 will also give you access to Generative Design, which is something Inventor is not capable of at this time.  Since Inventor and Fusion 360 make it easy to share files between the products, you have the flexibility to design your preserves and obstacles in Inventor before sending the file to Fusion 360.  Alternatively, you can send the model to Fusion 360, then design your preserves and obstacles in Fusion 360.  Since, this workflow retains files associativity between the products, if the Inventor model changes, Fusion 360 can be easily updated to reflect that change.  This is such a powerful workflow and because I strongly feel that Inventor users should be looking for ways to incorporate it into their workflows, MESA has created a class on Generative Design for Inventor Users.  

Here is an overview of what is covered in MESA's Generative Design for Inventor Users course.


I still remember when I started using Inventor, AutoCAD users were asking, "When is Autodesk going to stop making AutoCAD and make me use Inventor?"  That was over 13 years ago and I don't see that happening any time soon.  I feel the same about the Inventor or Fusion 360 discussion.  So we can stop asking Inventor OR Fusion 360 and start thinking in terms of Inventor AND Fusion 360.  The two products work very well together and are so similar that users should be able to jump back and forth without much effort.  By finding ways to leverage the strength of each tool, users will be able to design and manufacture better products easier than they were just using Inventor.

Friday, July 2, 2021

Printing from Fusion 360 Gcode

If you read the last blog post, which was about creating additive manufacturing toolpaths and gcode in Fusion 360, here is a video about printing that model.



Thursday, July 1, 2021

Fusion 360 Additive Manufacturing

I am always looking for different ways to accomplish tasks because you never know when a new approach will be better.  It might be easier, quicker, or provide better results.  I find myself doing this in all aspects of life.  I drive my wife crazy because even after I decide on an approach to something, I am likely to consider alternate methods.  This idiosyncrasy is partly how I have acquired the 3D modeling knowledge I have. The latest workflow I explored was the ability of Fusion 360 to create additive manufacturing toolpaths.

When I got a 3D printer back in February, my workflow quickly evolved into designing projects in Fusion 360 and exporting an STL file.  Then I would use Ultimaker Cura as my slicing program.  From there, I could create the necessary gcode for the printer.

Fusion 360 added the ability to create additive toolpaths a while ago and I had it on my list of functions to check out.  So, yesterday I finally decided to give it a chance.  One aspect of this process that is really nice is that I don't have to worry about exporting an STL file.  I can just jump into the Manufacturing workspace and create my setup and have it generate my toolpath.

For my test, I used a design that I had previously created a setup for subtractive manufacturing.  I just created a separate setup for the additive toolpath.  It was very convenient to be able to have both types of toolpaths in the same file, which of course are dynamically linked to the actual design.  In my normal workflow, if the design changed, I would have to remember to export the STL again.

One issue I had was that there was not a default Print Setting for 1.75 mm PLA.  I had to copy one for 2.85 mm PLA and modify it to match my desired settings.  That wasn't a big issue, but it was something that I had to workaround.  I was somewhat surprised that 1.75 mm PLA was not one of the defaults, from my experience that seems to be the most common filament size.  When I created the new setting for 1.75 mm PLA, I was able to save it as a cloud setting, so now that collection of settings will follow me from machine to machine and I will not have to create it again.

I will say that the Print Settings have a ton of options.  For someone that is relatively new to 3D printing, it was a little overwhelming to see all those settings.  I am just not experienced enough to know exactly what to set for some of them.  I did change the few that I knew I wanted to change and left the rest as the defaults.

Here is a video I made that walks you through the process I used to use Fusion 360 to create my Additive Manufacturing gcode.


The next step is to actually print from this gcode.  I plan on printing this part from this gcode to see how it turns out.  I will post about that soon, so please check back to see my results.

Wednesday, June 9, 2021

Fusion 360 Machine Simulation Preview

 In October of 2020, Autodesk acquired technology from a company named CAMplete.  The technology was capable of several functions, one of the most notable was running your CAM simulation in the context of the CNC machine.  When I heard of the acquisition, I was pretty excited because I knew that this would be a great addition to the CAM workflows I was familiar with in Fusion 360 and Inventor.  My only questions were how the functionality was going to be rolled out to Fusion 360 and/or Inventor and what it would look like.

I believe we have seen the beginning of that technology being rolled out to Fusion 360.  There is nothing in the documentation that says this is the CAMplete technology, but it is pretty obvious that the new Machine Simulation Preview in Fusion 360 is based on that CAMplete technology.  

Since this is a preview feature, you will have to enable it in your Fusion 360 Preferences.  At the bottom of the menu in the left pane of the Preferences dialog is Preview Features.  If you click on that, you can then look through all the preview features or filter by Workspace.  You will be looking for the function called Machine Simulation.


Once that is enabled in your Machine Library dialog, you will now see a filter option for Simulation Ready.


If a machine that is simulation-ready is defined in a Setup, you will then see the machine when the Setup is selected in the browser or when you are simulating a setup.


That is all you need to do, you can just program your toolpaths like you would normally do.  I really like this new function.  I think it will give CNC programmers more clarity into what the toolpath will look like when running the program on the machine.

If you would like to see this preview function in action; here is a video demo I created to show how this works.
  

Monday, May 24, 2021

Inventor Feature Presets

With the launch of Inventor 2022, Autodesk added several feature enhancements that you might already be using.  One feature that really isn't new, but is now available in more commands is Presets.  I haven't covered Presets before in this blog and I recently took a deep dive into Presets to understand how they work.  I figured that I would use this opportunity to share what I have learned.

Presets are a great way to save some time if you do the same type of operations, or features, often.  I can say that you will likely find that Presets are offered in certain commands that you may not have a need to leverage them in too.  The last time I checked Presets were available for Holes, Threads, Coils, Sweeps, Insert Frame (from Frame Generator), Surface Symbols (2D drawings), and Weld Symbols (2D drawings).

The idea behind Presets is that I can save a group of settings for a specific feature for future reuse.  One of the first commands to get Presets was the Hole command.  I really wished this was available when I had my last job.  Creating .190 diameter thru-holes was a pretty common feature that I needed to create.  With the use of Presets, I could have created that type of hole and leveraged that every time I needed to create that type of hole.  

Presets can also be standardized and shared across multiple users.  When Presets were introduced, Inventor project files added a mapping to a directory for them to be shared.  


Once you define a preset, Inventor will save a file in that directory for that feature type.



Creating presets is very easy.  All you have to do is set up the feature with all the necessary settings, then you click on the plus sign at the top of the feature dialog.


Inventor will name the preset by combining the attributes of that feature, however, you can customize the name to suit your needs.


From now on, when you want to apply that feature, you just need to select the preset from the drop-down menu.  You will still be able to override any of the predefined parameters.  So you can think of this as more of a feature template that can be leveraged, but you can still modify the parameters after you apply the preset.

If you would like to see the Hole Presets in action, here is a demo video I created.