Innovative companies are using simulation early in the product development process to improve and optimize product designs. Companies deploying up-front simulation to their product design teams require simulation software that is easy-to-use, provides accurate simulation results and allows customization to enforce best practices. Such design engineering simulation software allows teams to develop and refine design ideas early in the design cycle when the cost of making design changes is still low.
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Is your comapny designing or using electronics that are:
If so then you could potentially be a victim of signal integrity failure!
Join us August 17th, 2016 at 1 pm Pacific Time for a free webinar covering an introduction to Signal Integrity
This is a high-level introduction that will cover:
Followed by a Q&A session afterwards!
Click Here to register for this event and be sure to add it to your calendar to receive reminders.
Can’t make it? We suggest you register regardless, as our webinars are recorded and sent out along with a PDF of the presentation to our contacts within 24 hours of the presentation finishing.
Almost everyone in the technology industry agrees: the Internet of Things, or IoT, is “the next big thing.” Taking products and connecting them to the internet will change how people live their lives and how companies do their work. In “What you need to consider when designing for the Internet of Things” I explain three suggestions for designing an IoT device.
Engineering is all around us, but most people don’t think about how important engineering is to our modern lives. In “Flaming hoverboards: Why engineering matters” I take a look at a specific example of where a lack of engineering can cause problems.
At PADT we provide help to many of our customers who have trouble with their ANSYS simulations. At the top level, though, there are some computer skills for Windows that we consider basics that every engineer should know. If these are skills you already have in your tool belt, fantastic! If not, hopefully this information will help you be more effective in your simulation tasks.
Also, since most of us have been or are currently being updated to Windows 10, I’m providing the instructions for Windows 10. Windows 7 is similar, though.
Second-hand computers or second-hand laptops? Second-hand computers and second-hand laptops are an excellent solution for various computer tasks. At Computers R Us, you can find high quality Used Laptop Shop.
1. Run as Administrator
This allows us to run programs, a.k.a. “apps” with administrator privilege, even if our login credentials don’t allow this level of usage. This is the case for most users of engineering software. Certain components of ANSYS, including the CAD Configuration Manager and the Client ANSLIC_ADMIN Utility require changes to your computer that non-admin rights won’t allow. By running as administrator, we allow the program to make the needed changes.
To do this, click the Start Menu, then find the program (app) you need to run in the resulting list, such as the Client ANSLIC_ADMIN Utility, but one important thing to keep is mind is to use a privacy filter, it is important to maintain your privacy. Next, right click on that program, select More with the left mouse button, then select Run as Administrator with the left mouse button. If you are prompted to allow changes to your system, click Yes. Here is what it will look like:
2. View File Extensions
When using Windows Explorer, now known as File Explorer in Windows 10, by default you probably won’t see file extensions. Instead, you’ll see the prefix of files, but won’t see the endings of the file names. This will be the case when browsing for files to open or save as well. Sometimes you can rely on the icons associated with a file to know which program it’s associated with or the Type field in the list view, but sometimes there are conflicts. For example, an ANSYS Mechanical APDL macro file will have the extension .mac. You can probably guess that there is at least one other major company that can have software that uses that extension. By viewing the file extensions, even if the icons are wrong, we can more easily identify the files we need. Here is how it’s done:
Click Start, then File Explorer:
The default view using “Details” in File Explorer will look something like this (file names don’t include extensions):
To view the extensions, we click on the View menu in File Explorer, then Options, then Change Folder and Search Options.
The way I set this option for all folder on my computer is to then click on the View tab in the resulting small window, then uncheck the box for Hide extensions for known file types, then click Apply to Folders, then click OK.
Now the list view (using Details under the View menu) in File Explorer looks like this, with each file showing its extension in the list:
3. Define and Edit Environment Variables
Environment Variables are values that are used by certain programs to define settings. For example, an environment variable can be used to specify the license server for certain programs. It’s good to know how to define and edit these if needed. To do this, we bring up the control panel. In Windows 10, click on the Start button, then Settings:
A quick way to get there is to type “environment” in the search window in the resulting Settings window:
The search should find Edit the System Environment Variables. Click on that:
In the resulting System Properties window, click on the Environment Variables button in the Advanced tab:
A new window will open with a list of currently defined User variables (just for your login) and System variables (for anyone who is logged in), like this:
You can click on an environment variable to edit it using the Edit… button, or you can click on the New… button to create a new one. One ANSYS-related environment variable that occasionally needs to be set is ANSYSLMD_LICENSE_FILE. This is only needed if the default license server specifications aren’t working for some reason. You won’t need to set this under normal circumstances. Just in case, here is how to define it, using the New… button under System variables. We type in the Variable Name, in this case ANSYSLMD_LICENSE_FILE and then the Variable Value, which in this example is 1055@myserver.
When done defining and editing environment variables, we click on the OK button to complete the action and get out of that environment variable-related windows.
4. Check Usage of Your Computer Resources
As simulation experts, we are often pushing the limits of our computer resources. It’s good to know how to check those. First is disk space. An easy way to check disk space is to bring up File Explorer again. Click on This PC on the left side. This will give you a snapshot of the available space on each hard drive that is accessible on this computer:
Next, we may want to check CPU or memory utilization. Perhaps we want to make sure that our solution is running on multiple cores as we have requested.
To do this, hold down the Alt, Control, and Delete keys on the keyboard, all at the same time. Then click on Task Manager in the resulting window (it will look for a second like your computer is going to restart – it won’t actually do that).
In the resulting Task Manager window, click on More details:
In the resulting window, we can click on the Performance tab and view, for example, the current memory utilization, or we can click on Open Resource Monitor and get even more details, including utilization on each CPU:
5. Search for Large Files
It’s very common in the simulation world to end up filling up your disk drives. Therefore, it’s good to be able to find large files so we can delete them if they are no longer needed. For a simple way to do this, we’ll start with File Explorer again. This time, we’ll click in the search window at upper right, but won’t actually type in anything. We just want the search tools menu to appear:
Next, click on Search under Search Tools, followed by Size, then Gigantic (I will argue that 128 MB isn’t all that gigantic in the simulation world, but Microsoft hasn’t caught up with us yet):
Windows will now perform a search for files larger than 128 GB. If any of these are no longer needed, you can right click and delete them. Just make sure you don’t delete any files that are truly needed!
That completes our discussion on 5 computer skills every engineer should know. In conclusion, these basic skills should help you be more productive over time as you perform your simulation tasks. We hope you find this information useful, if it is is not enough, than visit this website for more infromation.
Also read: Windows SQL Server by SaveOnIT.Com.
It’s August and the activities keep coming. Those of us in the Tempe office managed to travel to cooler climates in July, and we have pictures to prove it below. This month’s events are mostly online. As always, check back to see if we have added anything. You can also see a list of events on our homepage and on the right column of the blog.
August 8-10: Austin, TX
2016 Annual International Solid Freeform Fabrication Symposium
This event is the academic side of 3D Printing. Less about the business and splash of the industry, this symposium focuses on R&D around the technology of freeform fabrication. PADT’s very own Dhruv Bhate will be there presenting a paper and interacting with other researchers in industry and academia.
August 15: Phoenix, AZ
AZ Additive Manufacturing Committee Meeting
Industrials leaders in 3D Printing across Arizona will be gathering for this month’s committee meeting at PADT. After the normal discussions, Dhruv Bhate will give a presentation then a tour of our 3D Printing resources.
We have several great Webinars on tap for August. All PADT webinars are recorded, so even if you can’t make the specified time register and we will send you a link to the recording.
|Wednesday, August 10, 2016 – 12:00 PM AZ/PDT, 1:00 PM MDT
ANSYS AIM: Simulation For Product Design Engineers
|Wednesday, August 24, 2016 – 12:00 PM AZ/PDT, 1:00 PM MDT
ANSYS AIM: Democratize Simulation for Your Design Engineers
|Thursday, September 1, 2016 – 12:00 PM AZ/PDT, 1:00 PM MDT
ANSYS AIM: Increase Simulation Realism with Multiphysics
Watch this space for the date and registration link.
July Events in Review
Last month was all about 3D Printing, with a booth in Tucson and a road show to show off a brand new printer.
The ACTE AZ event in Tucson is always a fantastic chance for us to meet with our education customers and show educators why industrial quality systems are the right solution for classrooms and labs. The team had a great time… but didn’t send any pictures.
The “Full Color 3D Printer Road Show” was a big success. We started in Denver at a Brewery (we need to do this more often) with great presentations and a ton of sample parts that highlight the capability of the new Stratasys J750. We then moved the machines and parts on to Downtown Salt Lake City and where the interaction was fantastic amongst many veteran users. The final stop was in Scottsdale Arizona where we had our largest crowd and more great interaction.
The Denver event was on the local Money Talk radio station. You can listen to the interview here.
Not to be outdone, a local TV station covered the Arizona event. That clip can be found here.
Product design engineers are increasingly under pressure to complete product designs faster so innovative products can reach the market sooner. Performing up-front simulation as part of the product development process can accelerate designing optimized products and reduce costly physical prototypes. To successfully implement simulation early in the product development process, simulation software must be easy-to-use and cover all the necessary physics that impact product designs.
Join us for this webinar to discover how AIM delivers unparalleled ease-of-use for simulation driven product development, and learn how design engineers can benefit from using simulation early in the product development process.
This webinar will be held on August 10th from 1:00 pm – 2:00 pm PT
Click Here to register for this webinar
Is PolyJet MED610 truly biocompatible? And what does that mean anyway?
A couple of months ago, our product development team contacted me to see if I could 3D print them a small bio-compatible masking device that was needed for temporary attachment to an invasive device prior to insertion for surgery. That led me to investigate all the different bio-compatible materials we did have access to at PADT on our FDM (Fused Deposition Modeling) and PolyJet machines. Given the tiny size and high detail required in the part, I decided to opt for PolyJet, which does offer the MED610 material that is claimed to be biocompatible. As it so happens, we have an Objet Eden 260V PolyJet machine that has been dedicated to running MED610 exclusively since it’s installation a year ago.
We printed the mask, followed all the post-processing instructions per supplier recommendations (more on that later) and delivered the parts for further testing. And that is when I asked myself the questions at the top of this post.
I set off on a quest to see what I could find. My first stop was the RAPID conference in (May 2016), where the supplier (Stratasys Inc.) had a well-staffed booth – but no one there knew much about MED610 apart from the fact that some orthodontists were using it. I did pick up one interesting insight: one of the engineers there hypothesized that MED610 was not very popular because it was cost-prohibitive since its proper use required machine dedication. I then went to the Stratasys Direct Manufacturing (a service bureau owned by Stratasys) booth, but it turned out they don’t even offer MED610 as a material option for service jobs – presumably because of the low demand for this material, consistent with our own observations.
So I took a step back and began searching for all I could find in the public domain on MED610 – and while it wasn’t much, here is the summary of my findings that I hope help anyone interested in this. I categorize it in three sources of information: claims made by the supplier, published work on in vitro studies and finally, some in vivo animal trials. But first, we must ask…
What does it mean for a Material to be Biocompatible?
A definition by Williams (The Williams Dictionary of Biomaterials, 1999) is in order: “Biocompatibility is the ability of a material to perform with an appropriate host response in a specific application.” So if PolyJet MED610 is to be called biocompatible, we must ask – what application do we have in mind? Fortunately, the supplier has a recommendation.
MED610 was launched by Objet in 2011 (Objet was acquired by Stratasys in 2012) as a biocompatible material, ideal for “applications requiring prolonged skin contact of more than 30 days and short-term mucosal-membrane contact of up to 24 hours“. Stratasys claims that parts printed according to Objet MED610 Use and Maintenance Terms were evaluated for biocompatibility in accordance with standard “DIN EN ISO 10993-1: 2009, Biological Evaluation of Medical Devices-Part 1: Evaluation and testing within a risk management process. This addresses cytotoxicity, genotoxicity, delayed hypersensitivity, and USP plastic Class VI, which includes the test for irritation, acute systemic toxicity and implantation”. Unfortunately, the actual data from the biocompatibility study conducted by Objet have not been made publicly available.
It is important to remember that Stratasys publishes a “Use and Maintenance Terms” document that details the steps needed not just to clean the part after printing, but also on the proper setup of the machine for ensuring best chances of meeting biocompatibility requirements. These are published online at this link and include a 3 hour soak in a 1-percent NaOH solution, a 30 min soak in IPA and multiple water jet rinses, among other steps. In other words, the claimed biocompatibility of MED610 is only valid if these instructions are followed. These steps are primarily driven by the need to completely remove supports and any support-residue, but it is not clear if this is needed if a part can be printed without supports. Given such strong process dependencies, it is only to be expected that Stratasys provide a disclaimer at the end of the document clarifying that the users of their machines are responsible for independently validating biocompatibility of any device they make with MED610.
The next question is: have there been any relevant published, independent studies that have used MED610? In my search, I could only find two instances, which I discuss below.
Primary Human Cells Response (In Vitro)
In a recent (January 2016) study published in the Journal of Medical and Biological Engineering, Schmelzer et al. studied the response of primary human cells to four 3D printed materials in vitro: ABS, PC, PLA and MED610 – the only such study I could find. All samples instead went through a 100% ethanol brief rinse and were washed 5 times with de-mineralized water – this seems like a less stringent process than what the supplier recommends (3 hour 1-percent NaOH solution soak, 30 minutes IPA soak and 10 times waterjet blasting) but was designed to be identical across all the materials tested.
There were some very interesting findings:
- Different cells had different responses:
- MED610 had the most negative impact on cell viability for keratinocytes (epidermal cells that produce keratin) – and the only material that showed statistically significant difference from the control.
- For bone marrow mesenchymal (stem) cells, a different effect was observed: direct culture on ABS and PC showed significant growth (7X compared to control) but MED610 and PLA showed no significant effect
- Surface Roughness influences cell attachment and proliferation:
- In agreement with other work, the authors showed that while rougher surfaces promote initial cell attachment, subsequent cell proliferation and overall cell numbers are higher on smoother surfaces. The MED610 samples had rougher surfaces than the FDM samples (possibly due to the use of the “matte” finish option) and could be one of the contributors to the observed negative effects on cell viability, along with the leached contents from the specimen.
Glaucoma Drainage Device (In Vivo, Rabbit studies)
A group of Australian researchers published a 2015 paper where they designed and used PolyJet MED610 to manufacture a Glaucoma Drainage Device (GDD). They selected PolyJet because of its ability to resolve very fine details that they needed for the device. Importantly, the purpose of this study was to assess the effect of different design parameters on the effectiveness of the device (relieving intraocular pressure). The device was implanted into rabbit eyeballs where it remained for up to 4 weeks.
The devices were printed on a Connex 350 PolyJet machine, after which the supports were removed from the devices with a water jet and “were repeatedly washed and inspected for consistency and integrity.” Tubes were attached with Silicone adhesive and the entire assembly was then “washed and sterilized with a hospital-grade hydrogen peroxide system before use”. The researchers did not examine the cellular and extracellular reactions in great detail, but did conclude that the reactions were similar between the MED610 device and the more standard polypropylene injection-molded device.
A short video recorded by some of the researchers as part of a Bioprinting course also provides some details into the 3D printing aspects of the work done.
In conclusion, the question I posed at the start of this post (Is PolyJet MED610 truly biocompatible?) is too simplistic. A process and a material together are not sufficient – there are procedures that need to be defined and controlled and further and more importantly, biocompatibility itself has to be viewed in the context of the application and the specific toxicity and interaction demands of that application. And that brings us to our key takeaways:
- MED610 is only recommended at best for applications requiring prolonged skin contact of more than 30 days and short-term mucosal-membrane contact of up to 24 hours and there is no data to dispute the suppliers claim that it is biocompatible in this context once all recommended procedures are implemented
- The work done by Australian researchers in using PolyJet MED610 for devoloping their Glaucoma Drainage Device in animal trials is perhaps the best example of how this material and the technology can be pushed further for evaluating designs and hypothesis in vivo when really fine features are needed. Stratasys’s FDM PC-ISO or ABS M30i materials, or other FDM extrusion capable materials like PLA, PCL and PLGA may be better options when the resolution allows – but this is a topic for a follow-on blog post.
- More in vitro work needs to be done to extend the work done by Schmelzer et al., which suggests that MED610 potentially has leachables that do impact cell viability negatively. Specifically, effects of surface finish (“matte” vs “gloss”) and sterilization on cell viability is a worthwhile follow-on step. In the interim, MED610 is expected to perform well for mucosal membrane contact under 24 hours (and why this is a great technology for dental guides and other temporary in-mouth placement).
If you have any thoughts on this matter or would like to collaborate with us and take advantage of our access to a PolyJet printer that is dedicated to MED610 or other bio-compatible FDM materials, as well as our extensive post-processing and design & analysis facilities, please connect with me on LinkedIn or send us a note at firstname.lastname@example.org and cite this blog post.
Thanks for reading!
- Stratasys Bio-compatible Materials Page: http://www.stratasys.com/materials/polyjet/bio-compatible
- PolyJet MED610 Data Sheets: http://www.stratasys.com/materials/material-safety-data-sheets/polyjet/dental-and-bio-compatible-materials
- Schmelzer, E., Over, P., Gridelli, B., & Gerlach, J. (2016). Response of Primary Human Bone Marrow Mesenchymal Stromal Cells and Dermal Keratinocytes to Thermal Printer Materials In Vitro. Journal of Medical and Biological Engineering, 36, 153-167.
- Ross C, Pandav S, Li Y, et al. Determination of Bleb Capsule Porosity With an Experimental Glaucoma Drainage Device and Measurement System. JAMA Ophthalmol.2015;133(5):549-554. doi:10.1001/jamaophthalmol.2015.30.
- Glaucoma case study in online course on Bioprinting, University of Woolongong, Future Learn, https://www.futurelearn.com/courses/bioprinting/3/steps/87168
Our loop around the Southwest with the new Stratasys J750 Full Color 3D Printer finished strong with a well attended gathering at ASU’s Skysong in Scottsdale. The event was so popular, Channel 10 did a story on it. Over 130 people signed up to learn more about this fantastic device, get caught up on latest industry trends, and talk with other users of Additive Manufacturing.
This event had a great mix of users from multiple industries as well as students and people wanting to just learn more about the technology.
The presentations were a big hit from every seminar, and Dhruv’s was especially popular in Arizona. You can download the presentations here:
Eric Miller’s Presentation on Design for 3D Printing:
Dhruv Bhate’s Overview of Additive Manufacturing:
James Barker and Mario Vargas’s Introduction of the Stratasys J750:
During the breaks and after the presentations, we had a chance to interact one-on-one with customers, show off parts, and answer questions. If you have any questions, please feel free to contact us at 480.813.4884 or email@example.com.
Lastly, we were visited by local TV channel 10, KSAZ who did a short but really informative segment on the show and the Stratasys J750:
The second stop on our trip around the Southwest for Stratasys’ new J750 Full Color 3D Printer was in fantastic downtown Salt Lake City. This device is reinventing 3D printing, and we are showing it off in person so people can see it up close along with holding incredible parts it makes in their hands.
Next stop if Phoenix – sign up here!
The 3D Printing community in Utah is very mature and the attendees were mostly very experienced users of many different additive manufacturing technologies. So we focused on real world applications for the J750 as well as other Stratasys systems.
We were fortunate enought to have a customer, Ultradent, present the fantastic ways that they use their FDM and Polyjet printers to make prototypes, tooling, and production parts.
As is usual in this type of an event, the discussion between and after presentations are the best part. People from Aerospace, sporting goods, medical devices, and consumer products swapped stories, suggestions, and tips.
It was also a family affair. with Jame Barker’s latest family addition was in attendence to help spread the word on the value of 3D Printing with Stratasys solutions:Beyond the little guy, the other hit of the afternoon was the J750. As seasoned additive manufacturing profesionals they see the incredible leap forward this machine represents – truly reinventing 3D Printing and opening up a huge range of oportunities.
As engineers, we struggle with using social networks to market our company. Engineers are not as in to social networking and they are adverse to anything that looks like a sale. “The five C’s of effective social network marketing” goes over some of the things that have worked for PADT and should help similar tech companies get greater value – Clear Messaging, Consistency, Content, Conciseness, and Cross Platform.
Having the right product development team is critical to the successful development of a new product. In “How to assemble the right product development team” I take a look at what PADT has learned through the years about what makes a great team.
Denver was the first stop on a trip around the Southwest for Stratasys’ new J750 Full Color 3D Printer. We are showing this machine that is reinventing 3D printing off in person so people can see the device up close and hold the incredible parts it makes in their hands.
The Denver event was hosted by St. Patrick’s Brewery in Littleton, right down the street from PADT’s Colorado Office. Several customers and PADT employees gave talks on how to better use 3D Printing, including a presentation from Mario Vargas on the new Stratasys J750.
On top of all of that, local radio station KDMT, Denver’s Money Talk 1690, did a live broadcast from the event. Radio Waves have huge collection of radio stations. You can listen in here. Again, PADT employees and customers talked about 3D Printing as well as the new Stratasys J750.
We also made the local paper, check that out here.
We are pleased to announce that PADT has been awarded a grant from America Makes to further our research into combining our three favorite things: Simulation, 3D Printing, and Product Development. We will work with our partners at ASU, Honeywell Aerospace, and LAI International to study lattice structures created in 3D Printing, how to model them in ANSYS simulation software, and then how to use that information to drive product design.