Cellular Design Strategies in Nature: A Classification

What types of cellular designs do we find in nature?

Cellular structures are an important area of research in Additive Manufacturing (AM), including work we are doing here at PADT. As I described in a previous blog post, the research landscape can be broadly classified into four categories: application, design, modeling and manufacturing. In the context of design, most of the work today is primarily driven by software that represent complex cellular structures efficiently as well as analysis tools that enable optimization of these structures in response to environmental conditions and some desired objective. In most of these software, the designer is given a choice of selecting a specific unit cell to construct the entity being designed. However, it is not always apparent what the best unit cell choice is, and this is where I think a biomimetic approach can add much value. As with most biomimetic approaches, the first step is to frame a question and observe nature as a student. And the first question I asked is the one described at the start of this post: what types of cellular designs do we find in the natural world around us? In this post, I summarize my findings.

Design Strategies

In a previous post, I classified cellular structures into 4 categories. However, this only addressed “volumetric” structures where the objective of the cellular structure is to fill three-dimensional space. Since then, I have decided to frame things a bit differently based on my studies of cellular structures in nature and the mechanics around these structures. First is the need to allow for the discretization of surfaces as well: nature does this often (animal armor or the wings of a dragonfly, for example). Secondly, a simple but important distinction from a modeling standpoint is whether the cellular structure in question uses beam- or shell-type elements in its construction (or a combination of the two). This has led me to expand my 4 categories into 6, which I now present in Figure 1 below.

Figure 1. Classification of cellular structures in nature: Volumetric – Beam: Honeycomb in bee construction (Richard Bartz, Munich Makro Freak & Beemaster Hubert Seibring), Lattice structure in the Venus flower basket sea sponge (Neon); Volumetric – Shell: Foam structure in douglas fir wood (U.S. National Archives and Records Administration), Periodic Surface similar to what is seen in sea urchin skeletal plates (Anders Sandberg); Surface: Tessellation on glypotodon shell (Author’s image), Scales on a pangolin (Red Rocket Photography for The Children’s Museum of Indianapolis)

Setting aside the “why” of these structures for a future post, here I wish to only present these 6 strategies from a structural design standpoint.

  1. Volumetric – Beam: These are cellular structures that fill space predominantly with beam-like elements. Two sub-categories may be further defined:
    • Honeycomb: Honeycombs are prismatic, 2-dimensional cellular designs extruded in the 3rd dimension, like the well-known hexagonal honeycomb shown in Fig 1. All cross-sections through the 3rd dimension are thus identical. Though the hexagonal honeycomb is most well known, the term applies to all designs that have this prismatic property, including square and triangular honeycombs.
    • Lattice and Open Cell Foam: Freeing up the prismatic requirement on the honeycomb brings us to a fully 3-dimensional lattice or open-cell foam. Lattice designs tend to embody higher stiffness levels while open cell foams enable energy absorption, which is why these may be further separated, as I have argued before. Nature tends to employ both strategies at different levels. One example of a predominantly lattice based strategy is the Venus flower basket sea sponge shown in Fig 1, trabecular bone is another example.
  2. Volumetric – Shell:
    • Closed Cell Foam: Closed cell foams are open-cell foams with enclosed cells. This typically involves a membrane like structure that may be of varying thickness from the strut-like structures. Plant sections often reveal a closed cell foam, such as the douglas fir wood structure shown in Fig 1.
    • Periodic Surface: Periodic surfaces are fascinating mathematical structures that often have multiple orders of symmetry similar to crystalline groups (but on a macro-scale) that make them strong candidates for design of stiff engineering structures and for packing high surface areas in a given volume while promoting flow or exchange. In nature, these are less commonly observed, but seen for example in sea urchin skeletal plates.
  3. Surface:
    • Tessellation: Tessellation describes covering a surface with non-overlapping cells (as we do with tiles on a floor). Examples of tessellation in nature include the armored shells of several animals including the extinct glyptodon shown in Fig 1 and the pineapple and turtle shell shown in Fig 2 below.
    • Overlapping Surface: Overlapping surfaces are a variation on tessellation where the cells are allowed to overlap (as we do with tiles on a roof). The most obvious example of this in nature is scales – including those of the pangolin shown in Fig 1.

Figure 2. Tessellation design strategies on a pineapple and the map Turtle shell [Scans conducted at PADT by Ademola Falade]

What about Function then?

This separation into 6 categories is driven from a designer’s and an analyst’s perspective – designers tend to think in volumes and surfaces and the analyst investigates how these are modeled (beam- and shell-elements are at the first level of classification used here). However, this is not sufficient since it ignores the function of the cellular design, which both designer and analyst need to also consider. In the case of tessellation on the skin of an alligator for example as shown in Fig 3, was it selected for protection, easy of motion or for controlling temperature and fluid loss?

Figure 3. Varied tessellation on an alligator conceals a range of possible functions (CCO public domain)

In a future post, I will attempt to develop an approach to classifying cellular structures that derives not from its structure or mechanics as I have here, but from its function, with the ultimate goal of attempting to reconcile the two approaches. This is not a trivial undertaking since it involves de-confounding multiple functional requirements, accounting for growth (nature’s “design for manufacturing”) and unwrapping what is often termed as “evolutionary baggage,” where the optimum solution may have been sidestepped by natural selection in favor of other, more pressing needs. Despite these challenges, I believe some first-order themes can be discerned that can in turn be of use to the designer in selecting a particular design strategy for a specific application.

References

This is by no means the first attempt at a classification of cellular structures in nature and while the specific 6 part separation proposed in this post was developed by me, it combines ideas from a lot of previous work, and three of the best that I strongly recommend as further reading on this subject are listed below.

  1. Gibson, Ashby, Harley (2010), Cellular Materials in Nature and Medicine, Cambridge University Press; 1st edition
  2. Naleway, Porter, McKittrick, Meyers (2015), Structural Design Elements in Biological Materials: Application to Bioinspiration. Advanced Materials, 27(37), 5455-5476
  3. Pearce (1980), Structure in Nature is a Strategy for Design, The MIT Press; Reprint edition

As always, I welcome all inputs and comments – if you have an example that does not fit into any of the 6 categories mentioned above, please let me know by messaging me on LinkedIn and I shall include it in the discussion with due credit. Thanks!

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New: PADT’s Medical Device Capabilities and Portfolio Presentation

We recently updated our slide presentation on PADT’s Medical Device product development capabilities that includes some examples of past work.  Our ISO 13485 certified team applies proven processes and deep industry experience across a wide spectrum of products.  Please take a look to learn more about how we help companies engineer their medical devices.

PADT-Medical-Overview-Portfolio-2017_03_22-2

 

You can learn more here and if you have any questins, simply email info@padtinc.com or call 480.813.4884.

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Phoenix Business Journal: Instant messaging and business communication

hey  you didn’t read my email

you comming to the meeting?

 sorry

dialing in

Instant messaging has moved from a personal communication tool to an important part of business communication. But if we use it like email, it will loose its impact. “Intant messaging and business communication” looks at the topic.

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Phoenix Business Journal: How can technology further art?

Technology is an awesomely creative endeavor – innovation and inspiration is combined with science to create new products and tools for people and businesses. It is creative, but it’s not art. In “How can technology further art” I look at what technology can do to open new ways for people to express themselves and to make art more accesable.

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Phoenix Business Journal: ​What the heck is happening? There is too much going on in Arizona tech

We have a problem now in the Arizona Tech community – there is just too much going on.  In “What the heck is happening? There is too much going on in Arizona tech” we look at how why this is a good thing and what we can to make it even better.

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ANSYS 18 – AIM Enhancements Webinar

We here at PADT are excited to share with you the updates that ANSYS 18 brings to the table for AIM: The easy-to-use, upfront simulation tool for all design engineers.

ANSYS AIM is a single GUI, multiple physics tool with advanced ANSYS technology under the hood. It requires minimal training and is interoperable with a wide range of ANSYS simulation products.

Join PADT’s application engineer Tyler Smith as he covers the new features and capabilities available in this new release, including:

  • Magnetic frequency response
  • One-way FSI for shell structures
  • Model transfer to Fluent
  • One-way magnetic-thermal coupling
  • and many more!

ANSYS AIM is a perfect tool for companies performing simulation with a CAD embedded tool, design engineers at companies using high end simulation, and even companies who have yet to take the plunge into the world of simulation.

Register for this webinar today and learn how you can take advantage of the easy-to-use, yet highly beneficial capabilities of ANSYS AIM.

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License Usage and Reporting with ANSYS License Manager Release 18.0

Remember the good old days of having to peruse through hundreds and thousands of lines of text in multiple files to see ANSYS license usage information?  Trying to hit Ctrl+F and search for license names.  Well those days were only about a couple months ago and they are over…well for the most part.

With the ANSYS License Manager Release 18.0, we have some pretty nifty built in license reporting tools that help to extract information from the log files so the administrator can see anything from current license usage to peak usage and even any license denials that occur.  Let’s take a look at how to do this:

First thing is to open up the License Management Center:

  • In Windows you can find this by going to Start>Programs>ANSYS Inc License Manager>ANSYS License Management Center
  • On Linux you can find this in the ansys directory /ansys_inc/shared_files/licensing/start_lmcenter

This will open up your License Manager in your default browser as shown below.   For the reporting just take a look at the Reporting Section.  We’ll cover each of these 4 options below.

License Management Center at Release 18.0

License Reporting Options

 

 

VIEW CURRENT LICENSE USAGE

As the title says, this is where you’ll go to see a breakdown of the current license usage.  What is great is that you can see all the licenses that you have on the server, how many licenses of each are being used and who is using them (through the color of the bars).  Please note that PADT has access to several ANSYS Licenses.  Your list will only include the licenses available for use on your server.

Scrolling page that shows Current License Usage and Color Coded Usernames

You can also click on Show Tabular Data to see a table view that you can then export to excel if you wanted to do your own manipulation of the data.

Tabular Data of Current License Usage – easy to export

 

 

 

VIEW LICENSE USAGE HISTORY

In this section you will be able to not only isolate the license usage to a specific time period, you can also filter by license type as well.  You can use the first drop down to define a time range, whether that is the previous 1 month, 1 year, all available or even your own custom time range

Isolate License Usage to Specific Time Period

Once you hit Generate you will be able to then isolate by license name as shown below.  I’ve outlined some examples below as well.  The axis on the left shows number of licenses used.

Filter Time History by License Name

1 month history of ANSYS Mechanical Enterprise

 1 month history of ANSYS CFD

Custom Date Range history of ANSYS SpaceClaim Direct Modeler

 

 

 

VIEW PEAK LICENSE USAGE

This section will allow you to see what the peak usage of a particular license during a particular time period and filter it based on data range.  First step is to isolate to a date range as before, for example 1 month.  Then you can select which month you want to look at data for.

Selecting specific month to look at Peak License Usage

Then you can isolate the data to whether or not you want to look at an operational period of 24/7, Monday to Friday 24/5 or even Monday to Friday 9am-5pm.  This way you can isolate license usage between every day of the week, working week or normal working hours in a week. Again, axis on left shows number of licenses.

Isolating data to 24/7, Weekdays or Weekday Working Hours

 Peak License Usage in March 2017 of ANSYS Mechanical Enterprise (24/7)

Peak License Usage in February 2017 of ANSYS CFD (Weekdays Only)

 

 

VIEW LICENSE DENIALS

If any of the users who are accessing the License Manager get license denials due to insufficient licenses or for any other reason, this will be displayed in this section.  Since PADT rarely, if ever, gets License Denials, this section is blank for us.  The procedure is identical to the above sections – it involves isolating the data to a time period and filtering the data to your interested quantities.

Isolate data with Time Period as other sections

 

 

Although these 4 options doesn’t include every conceivable filtering method, this should allow managers and administrators to filter through the license usage in many different ways without needing to manually go through all the log files.   This is a very convenient and easy set of options to extract the information.

Please let us know if you have any questions on this or anything else with ANSYS.

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DesignCon 2017 Trends in Chip, Board, and System Design


Considered the “largest gathering of chip, board, and systems designers in the country,” with over 5,000 attendees this year and over 150 technical presentations and workshops, DesignCon exhibits state of the art trends in high-speed communications and semiconductor communities.

Here are the top 5 trends I noticed while attending DesignCon 2017:

1. Higher data rates and power efficiency.

This is of course a continuing trend and the most obvious. Still, I like to see this trend alive and well because I think this gets a bit trickier every year. Aiming towards 400 Gbps solutions, many vendors and papers were demonstrating 56 Gbps and 112 Gbps channels, with no less than 19 sessions with 56 Gbps or more in the title. While IC manufacturers continue to develop low-power chips, connector manufacturers are offering more vented housings as well as integrated sinks to address thermal challenges.

2. More conductor-based signaling.

PAM4 was everywhere on the exhibition floor and there were 11 sessions with PAM4 in the title. Shielded twinaxial cables was the predominant conductor-based technology such as Samtec’s Twinax Flyover and Molex’s BiPass.

A touted feature of twinax is the ability to route over components and free up PCB real estate (but there is still concern for enclosing the cabling). My DesignCon 2017 session, titled Replacing High-Speed Bottlenecks with PCB Superhighways, would also fall into this category. Instead of using twinax, I explored the idea of using rectangular waveguides (along with coax feeds), which you can read more about here. I also offered a modular concept that reflects similar routing and real estate advantages.

3. Less optical-based signaling.

Don’t get me wrong, optical-based signaling is still a strong solution for high-speed channels. Many of the twinax solutions are being designed to be compatible with fiber connections and, as Teledyne put it in their QPHY-56G-PAM4 option release at DesignCon, Optical Internetworking Forum (OIF) and IEEE are both rapidly standardizing PAM4-based interfaces. Still, the focus from the vendors was on lower cost conductor-based solutions. So, I think the question of when a full optical transition will be necessary still stands.
With that in mind, this trend is relative to what I saw only a couple years back. At DesignCon 2015, it looked as if the path forward was going to be fully embracing optical-based signaling. This year, I saw only one session on fiber and, as far as I could tell, none on photonic devices. That’s compared to DesignCon 2015 with at least 5 sessions on fiber and photonics, as well as a keynote session on silicon photonics from Intel Fellow Dr. Mario Paniccia.

4. More Physics-based Simulations.

As margins continue to shrink, the demand for accurate simulation grows. Dr. Zoltan Cendes, founder of Ansoft, shared the difficulties of electromagnetic simulation over the past 40+ years and how Ansoft (now ANSYS) has improved accuracy, simplified the simulation process, and significantly reduced simulation time. To my personal delight, he also had a rectangular waveguide in his presentation (and I think we were the only two). Dr. Cendes sees high-speed electrical design at a transition point, where engineers have been or will ultimately need to place physics-based simulations at the forefront of the design process, or as he put it, “turning signal integrity simulation inside out.” A closer look at Dr. Cendes’ keynote presentation can be found in DesignNews.

5. More Detailed IC Models.

This may or may not be a trend yet, but improving IC models (including improved data sheet details) was a popular topic among presenters and attendees alike; so if nothing else it was a trend of comradery. There were 12 sessions with IBIS-AMI in the title. In truth, I don’t typically attend these sessions, but since behavioral models (such as IBIS-AMI) impact everyone at DesignCon, this topic came up in several sessions that I did attend even though they weren’t focused on this topic. Perhaps with continued development of simulation solutions like ANSYS’ Chip-Package-System, Dr. Cende’s prediction will one day make a comprehensive physics-based design (to include IC models) a practical reality. Until then, I would like to share an interesting quote from George E. P. Box that was restated in one of the sessions: “Essentially all models are wrong, but some are useful.” I think this is good advice that I use for clarity in the moment and excitement for the future.

By the way, the visual notes shown above were created by Kelly Kingman from kingmanink.com on the spot during presentations. As an engineer, I was blown away by this. I have a tendency to obsess over details but she somehow captured all of the critical points on the fly with great graphics that clearly relay the message. Amazing!

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How To Update The Firmware Of An Intel® Solid-State Drive DC P3600

How To Update The Firmware Of An Intel® Solid-State Drive DC P3600 in four easy steps!

The Dr. says to keep that firmware fresh! so in this How To blog post I illustrate to you how to verify and/or update the firmware on a 1.2TB  Intel® Solid-State Drive DC 3600 Series NVMe MLC card.

CUBE Workstation Specifications – The Tester

PADT, Inc. – CUBE w32i Numerical Simulation Workstation

  • 2 x 16c @2.6GHz/ea. (INTEL XEON e5-2697A V4 CPU), 40M Cache, 9.6GT, 145 Watt/each
  • Dual Socket Super Micro X10DAi motherboard
  • 8 x 32GB DDR4-2400MHz ECC REG DIMM
  • 1 x NVIDIA QUADRO M2000 – 4GB GDDR5
  • 1 x  Intel® DC P3600 1.2TB, NVMe PCIe 3.0, MLC AIC 20nm
  • Windows 7 Ultimate Edition 64-bit

Step 1: Prepping

Check for and download the latest downloads for the Intel® Solid-State DC 3600 here: https://downloadcenter.intel.com/product/81000/Intel-SSD-DC-P3600-Series

You will need the latest downloads of the:

Intel® SSD Data Center Family for NVMe Drivers
  • Intel® Solid State Drive Toolbox

  • Intel® SSD Data Center Tool

  • Intel® SSD Data Center Family for NVMe Drivers

Step 2: Installation

After instaling, the Intel® Solid State Drive Toolbox and the Intel® SSD Data Center Tool reboot the workstation and move on to the next step.

INTEL SSD Toolbox

INTEL SSD Toolbox

INTEL SSD Toolbox Install

Step 3: Trust But Verify

Check the status of the 1.2TB NVMe card by running the INTEL SSD DATA Center Tool. Next, I will be using the Windows 7 Ultimate 64-bit version for the operating system. Running the INTEL DATA CENTER TOOLS  within an elevated command line prompt.

Right-Click –> Run As…Administrator
Command Line Text: isdct show –intelssd

INTEL DATA Center Command Line Tool

INTEL DATA Center Command Line Tool

As the image indicates below the firmware for this 1.2TB NVMe card is happy and it’s firmware is up to date! Yay!

If you have more than one SSD take note of the Drive Number.

  • Pro Tip – In this example the INTEL DC P3600 is Drive number zero. You can gather this information from the output syntax. –> Index : 0

Below is what the command line output text looks like while the firmware process is running.

C:\isdct >isdct.exe load –intelssd 0 WARNING! You have selected to update the drives firmware! Proceed with the update? (Y|N): y Updating firmware…The selected Intel SSD contains current firmware as of this tool release.
isdct.exe load –intelssd 0 WARNING! You have selected to update the drives firmware! Proceed with the update? (Y|N): n Canceled.
isdct.exe load –f –intelssd 0 Updating firmware… The selected Intel SSD contains current firmware as of this tool release.
isdct.exe load –intelssd 0 WARNING! You have selected to update the drives firmware! Proceed with the update? (Y|N): y Updating firmware… Firmware update successful.

Step 4: Reboot Workstation

The firmware update process has been completed.

shutdown /n

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Using External Data in ANSYS Mechanical to Tabular Loads with Multiple Variables

ANSYS Mechanical is great at applying tabular loads that vary with an independent variable. Say time or Z.  What if you want a tabular load that varies in multiple directions and time. You can use the External Data tool to do just that. You can also create a table with a single variable and modify it in the Command Editor.

In the Presentation below, I show how to do all of this in a step-by-step description.

PADT-ANSYS-Tabular-Loading-ANSYS-18

You can also download the presentation here.

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Phoenix Business Journal: ​Emoticons as a way to communicate in business

It started with kids and texting, but now emoticons can be a possitive part of business communciation :-O   In “Emoticons as a way to communicate in business” I look at soem examples and why I think its a good thing ;-).

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AZ Business Magazine: It’s time for Arizona startups to grow up

At some point it’s time to get real.  “It’s time for Arizona startups to grow up” looks at how we need to stop focusing on getting ready for success and start achieving it.  We were pleased to be the first article in AZBigMedia.com‘s new “Silicon Desert Insider” blog shares my thoughts on how its time for some tough love. Brought to you by AZ Business Magazine, it focuses on the technology side of business in the Phoenix area.

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Experiences with Developing a “Somewhat Large” ACT Extension in ANSYS

With each release of ANSYS the customization toolkit continues to evolve and grow.  Recently I developed what I would categorize as a decent sized ACT extension.    My purpose in this post is to highlight a few of the techniques and best practices that I learned along the way.

Why I chose C#?

Most ACT extensions are written in Python.  Python is a wonderfully useful language for quickly prototyping and building applications, frankly of all shapes and sizes.  Its weaker type system, plethora of libraries, large ecosystem and native support directly within the ACT console make it a natural choice for most ACT work.  So, why choose to move to C#?

The primary reasons I chose to use C# instead of python for my ACT work were the following:

  1. I prefer the slightly stronger type safety afforded by the more strongly typed language. Having a definitive compilation step forces me to show my code first to a compiler.  Only if and when the compiler can generate an assembly for my source do I get to move to the next step of trying to run/debug.  Bugs caught at compile time are the cheapest and generally easiest bugs to fix.  And, by definition, they are the most likely to be fixed.  (You’re stuck until you do…)
  2. The C# development experience is deeply integrated into the Visual Studio developer tool. This affords not only a great editor in which to write the code, but more importantly perhaps the world’s best debugger to figure out when and how things went wrong.   While it is possible to both edit and debug python code in Visual Studio, the C# experience is vastly superior.

The Cost of Doing ACT Business in C#

Unfortunately, writing an ACT extension in C# does incur some development cost in terms setting up the development environment to support the work.  When writing an extension solely in Python you really only need a decent text editor.  Once you setup your ACT extension according to the documented directory structure protocol, you can just edit the python script files directly within that directory structure.  If you recall, ACT requires an XML file to define the extension and then a directory with the same name that contains all of the assets defining the extension like scripts, images, etc…  This “defines” the extension.

When it comes to laying out the requisite ACT extension directory structure on disk, C# complicates things a bit.  As mentioned earlier, C# involves a compilation step that produces a DLL.  This DLL must then somehow be loaded into Mechanical to be used within the extension.  To complicate things a little further, Visual Studio uses a predefined project directory structure that places the build products (DLLs, etc…) within specific directories of the project depending on what type of build you are performing.   Therefore the compiled DLL may end up in any number of different directories depending on how you decide to build the project.  Finally, I have found that the debugging experience within Visual Studio is best served by leaving the DLL located precisely wherever Visual Studio created it.

Here is a summary list of the requirements/problems I encountered when building an ACT extension using C#

  1. I need to somehow load the produced DLL into Mechanical so my extension can use it.
  2. The DLL that is produced during compilation may end up in any number of different directories on disk.
  3. An ACT Extension must conform to a predefined structural layout on the filesystem. This layout does not map cleanly to the Visual studio project layout.
  4. The debugging experience in Visual Studio is best served by leaving the produced DLL exactly where Visual Studio left it.

The solution that I came up with to solve these problems was twofold.

First, the issue of loading the proper DLL into Mechanical was solved by using a combination of environment variables on my development machine in conjunction with some Python programming within the ACT main python script.  Yes, even though the bulk of the extension is written in C#, there is still a python script to sort of boot-load the extension into Mechanical.  More on that below.

Second, I decided to completely rebuild the ACT extension directory structure on my local filesystem every time I built the project in C#.  To accomplish this, I created in visual studio what are known as post-build events that allow you to specify an action to occur automatically after the project is successfully built.  This action can be quite generic.  In my case, the “action” was to locally run a python script and provide it with a few arguments on the command line.  More on that below.

Loading the Proper DLL into Mechanical

As I mentioned above, even an ACT extension written in C# requires a bit of Python code to bootstrap it into Mechanical.  It is within this bit of Python that I chose to tackle the problem of deciding which dll to actually load.  The code I came up with looks like the following:

Essentially what I am doing above is querying for the presence of a particular environment variable that is on my machine.  (The assumption is that it wouldn’t randomly show up on end user’s machine…) If that variable is found and its value is 1, then I determine whether or not to load a debug or release version of the DLL depending on the type of build.  I use two additional environment variables to specify where the debug and release directories for my Visual Studio project exist.  Finally, if I determine that I’m running on a user’s machine, I simply look for the DLL in the proper location within the extension directory.  Setting up my python script in this way enables me to forget about having to edit it once I’m ready to share my extension with someone else.  It just works.

Rebuilding the ACT Extension Directory Structure

The final piece of the puzzle involves rebuilding the ACT extension directory structure upon the completion of a successful build.  I do this for a few different reasons.

  1. I always want to have a pristine copy of my extension laid out on disk in a manner that could be easily shared with others.
  2. I like to store all of the various extension assets, like images, XML files, python files, etc… within the Visual Studio Project. In this way, I can force the project to be out of date and in need of a rebuild if any of these files change.  I find this particularly useful for working with the XML definition file for the extension.
  3. Having all of these files within the Visual Studio Project makes tracking thing within a version control system like SVN or git much easier.

As I mentioned before, to accomplish this task I use a combination of local python scripting and post build events in Visual Studio.  I won’t show the entire python code, but essentially what it does is programmatically work through my local file system where the C# code is built and extract all of the files needed to form the ACT extension.  It then deletes any old extension files that might exist from a previous build and lays down a completely new ACT extension directory structure in the specified location.  The definition of the post build event is specified within the project settings in Visual Studio as follows:

As you can see, all I do is call out to the system python interpreter and pass it a script with some arguments.  Visual Studio provides a great number of predefined variables that you can use to build up the command line for your script.  So, for example, I pass in a string that specifies what type of build I am currently performing, either “Debug” or “Release”.  Other strings are passed in to represent directories, etc…

The Synergies of Using Both Approaches

Finally, I will conclude with a note on the synergies you can achieve by using both of the approaches mentioned above.  One of the final enhancements I made to my post build script was to allow it to “edit” some of the text based assets that are used to define the ACT extension.  A text based asset is something like an XML file or python script.  What I came to realize is that certain aspects of the XML file that define the extension need to be different depending upon whether or not I wish to debug the extension locally or release the extension for an end user to consume.  Since I didn’t want to have to remember to make those modifications before I “released” the extension for someone else to use, I decided to encode those modifications into my post build script.  If the post build script was run after a “debug” build, I coded it to configure the extension for optimal debugging on my local machine.  However, if I built a “release” version of the extension, the post build script would slightly alter the XML definition file and the main python file to make it more suitable for running on an end user machine.   By automating it in this way, I could easily build for either scenario and confidently know that the resulting extension would be optimally configured for the particular end use.

Conclusions

Now that I have some experience in writing ACT extensions in C# I must honestly say that I prefer it over Python.  Much of the “extra plumbing” that one must invest in in order to get a C# extension up and running can be automated using the techniques described within this post.  After the requisite automation is setup, the development process is really straightforward.  From that point onward, the increased debugging fidelity, added type safety and familiarity a C based language make the development experience that much better!  Also, there are some cool things you can do in C# that I’m not 100% sure you can accomplish in Python alone.  More on that in later posts!

If you have ideas for an ACT extension to better serve your business needs and would like to speak with someone who has developed some extensions, please drop us a line.  We’d be happy to help out however we can!

 

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Phoenix Business Journal: ​How technology can bring people together and bring down barriers

We talk about technology all the time and how it impacts our daily lives, good and bad.  “​How technology can bring people together and bring down barriers” takes a look at the social impact of technology when it comes to creating understanding and community.

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Phoenix Business Journal: Installing a metal 3-D printer was a lesson on working with regulators

While installing our new metal 3D Printer we learned a couple of important lessons on working with local inspectors.  In “Installing a metal 3-D printer was a lesson on working with regulators” we share what we captured.

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