Presentations for Mercy TechTalk

I’ll be giving to presentations today at Mercy Tech Talk. Here are the links from my presentations:

3D Printing in Education – 11:10 in N-17
Curious about 3D printing? We will walk through the basics of 3D printing and introduce simple programs for creating 3D models suitable for printing. No previous 3D modeling experience is needed. We will also look at some ways 3D printing can be worked into the curriculum and for fundraising.

Flipping with an iPad – 1:00 in Drama Studio
Have you thought about making videos to support your instruction? Maybe even a full flip? With an iPad you can create and distribute videos for your students. We will investigate several apps and accessories you can use to make compelling content for your students without the need for a computer.

Interactive Maps with Keynote and Gimp

When people are learning to make iBooks with iBooks Author they often want to have cool widgets for their students to interact with. As I’ve shown in previous posts, you can create some pretty easily with Keynote. I really like showing teachers how to use Keynote to do this because if they use a Mac they already have it. When you couple this with a free image editor, Gimp, you can do some really cool stuff.

The example here is not one I’ve used to teach my students, but one I used at last year’s iBookHack. From a teaching standpoint it might not be very good, I’m not really sure since I don’t teach social studies. It’s just an example of how you might create an interactive map to use with your students. The first video below walks you through using Gimp to create your maps. The second shows you how to use Keynote to bring them together as an interactive widget you can drop into an iBook.


Interactive Practice Widget Built in Keynote

I’ve been involved in iBooks Author teacher training with Anthony DiLaura for a few years now. You can find out about our hackathon coming up this summer at the ibookhack site.

While working on the iBookHack project I’ve gotten to meet some amazing educators. One of these is Tara Maynard. Tara saw a cool HTML5 math practice widget in an iBook and she wondered if it would be possible to put something like it in her own books. I showed her how she might reproduce the basic idea of the widget in Keynote and she went on to create this great template. She has shared it so you can use it as a starting point for your own practice widget. If you need a little help you can check out my video below.

The problem is shown, if there are accessibility concerns a button is included that will read the problem aloud to the student. Each problem can provide a hint to help aid students in independent practice and finally the solution is provided so students can get instant feedback to see if they were correct. Since it is made in Keynote the problem, hints, or solution can include pictures or videos as well. Overall it is a great interactive element to include in an iBook and doesn’t take a lot of technical skills to implement.

The core idea of this widget centers on creating a “Links Only” presentation in Keynote. If you need a little more information on this you should check out another video I made, which is also included below.

Getting Started with 3D Printing – Find a problem to solve

This week I went high-tech to go low-tech. When I taught physics I taught with a student centered pedagogy called Modeling Physics. In Modeling we have student collect data and then use that data to construct models to explain physics. Basically students do labs, graph the data, find an equation that fits their graph and then they turn that equation into a generic equation that can be used in other situations. Everything works great if you can get the students to collect really clean data and if you can actually convince them to think.

I don’t teach physics anymore, but our new physics teacher, Vance, also uses the Modeling Method. He built some apparatuses last week end to collect really good acceleration data. This is just a wood disk with a golf tee glued to the center of each side. This rolls down a pair of rails and is slow enough to allow students to get some really good data. I’d thought about building these myself in the past, but I knew it would be hard to do and that I’d probably screw it up. So I never constructed any. Vance did a fine job in his construction, but he ended up having all the problems I knew I would have had.

Enter the 3D printer. Looking at Vance’s system I knew I could knock something out on the 3D printer that would work. This is one of the coolest things about owning a 3D printer. You will see problems and begin to envision solutions. Once you start doing this the easier it becomes. The only risk is that you will quickly assume the 3D printer is the best tool for all jobs. As awesome as it is, it is not always the best way to solve every problem.

I spent about 10 minutes in Tinkercad on my design and then it took about an hour and a half to print. Vance tells me it worked great for the lab. I’m already envisioning modifications for future investigations. The design could be easily modified to investigate rotational inertia and energy, but maybe I’ll leave it to students to create these new designs.

Acceleration Paradigm Lab – Teacher Notes

Materials (for each group):

  • 2 bricks with holes or grooved sides
  • 2 five foot sections of electrical conduit
  • 1 wood disk with a golf tee sticking out of the center of each side, or 1 3D printed disk with cones out of each side
  • Dry erase marker
  • A metronome set to 60 peats/minute (or a computer program) – One for the entire class
Basic Procedure:
  • Set the conduit up as a pair of rails spaced appropriately for your rolling disk
  • Let the disk roll down the rails
  • Mark the position of the disk at 1 or 2 second intervals
  • Create a position vs. time graph and find the equation that fits the data (should be a quadratic)
  • Create a velocity vs. time data set and graph from the position data using the secant line created by each pair of points on the position graph. This graph should be linear.
  • Note: If the incline is too steep it will slide rather than roll.
Class discussion:
  • I always have students use the actual variables in their equations, no x’s or y’s. In addition all constants need units.
  • Once students have equations for both their position and velocity graphs I ask them what each constant represents and how they know. This is pretty easy for the velocity graph, but a little harder for the position graph. It leads to some great conversations and ultimately to a pair of generic equations we will use for the rest of the kinematics unit.
My 3D Model:
This is a part 6 of my series on 3D Printers in Education. Go back to earlier parts in the 3D printer series: Part 1Part 5

Interactive Video Widgets in iBooks

For the last couple of summers I had the pleasure to work along Tony DiLauraDave Bast and some great educators committed to making their own content with hopes of replacing traditional textbooks at iBooks Hackathons. I’d put together some material for those hackathons and I thought I’d share some of it here.
When I teach I try to always ask questions and never give answers. I want my students to struggle a bit and discover the answers through experimentation and discussion. This is very difficult to do in the videos I make. Due to the nature of video I don’t really give students time to think, nor do I give them a chance to investigate different answers. Derek Muller hit on a solution to this on his Veritasium YouTube Channel. YouTube allows you to put clickable hotspots on videos. Derek uses these to link to other videos he’s made. He set up a kind of choose your own adventure allowing viewers to think about different answers to questions and each answer has it’s own video.
I thought this was an awesome way to get students thinking and set out to try it myself. But as it turns out, these hotspots don’t work on mobile devices, including iPads. We’re in the midst of becoming a 1:1 iPad school, so I don’t want to rely on cool internet features that I know won’t work on mobile devices.
After some though, I realized I could create the same sort of effect using either Keynote or Tumult Hype. Once created I can drop them into an iBook as an interactive widget and my students will be able to actually grapple with questions in their book rather than simply being presented with the answers. Each solution has its own advantages and disadvantages. Here’s the version I made with Hype (I’m not sure this link will work correctly) to use with my students.
One big advantage with Keynote is it is easy to work with and if you have a Mac you probably already have it. Keynote’s biggest disadvantage is there is no way to control the video once it starts in an iBook widget. The video starts and then runs to completion, no pausing or rewinding.
In Hype you do have the video controls. The other big advantage in Hype is you can embed YouTube videos. I don’t know of any way to have YouTube videos auto-play in Hype. As far as I know, there is currently no way to embed a YouTube video in a Keynote. Embedding YouTube videos means you must have internet access to view, but it keeps the iBook size down to manageable levels. Unfortunately Hype is not free. It costs $30, but if you’re going to be making iBooks it might be worth it in the long run. Make sure you buy it through the Tumult Education Store to get the discounted price.

Instructions:

Make your Keynote Presentation “Links Only”:

Keynote for Interactive Video:



Hype for Interactive Video:

Putting YouTube Videos in Hype:

Getting Started With 3D Printing – PLA vs. ABS

There are two main types of plastic used in most FDM printers, polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS). ABS is the same plastic Legos are made from and PLA is a bioplastic typically derived from corn starch. I will not go into a lot of the technical differences, but will instead focus on the practical issues related to each type of plastic.

Each plastic has its own advantages and disadvantages. Most of the newest low cost printers available today will only print with PLA. In order to complete a successful print, the plastic must stick well to the print bed. Sometimes it may be beneficial to heat the print bed to 40-50°C for PLA. However, it is often not necessary and many commercially available printers designed to print with PLA do not have the ability to heat the print bed at all. ABS requires a heated print bed for parts to stick. It is necessary to heat the print bed to 110-130°C when printing with ABS. This is quite hot, remember water boils at 100°C.

There are other practical concerns related to both plastics to consider. ABS shrinks substantially more than PLA while cooling. This can often cause parts to warp. When a part warps the edges or corners lift off the platform. This can lead to a part becoming completely unstuck from the platform or even if it stays in place may be completely unusable. ABS also gives off some fumes while printing. They are not overwhelming, but they are noticeable. One of my colleagues has sever allergies and asthma and reacts to just about any type of smell or fumes in the air. She never had a problem with the ABS fumes in the room.

Since PLA doesn’t shrink as much as it cools it is much less prone to warping and the finished parts are much closer to the intended dimensions. This difference often doesn’t mean much. However, if you are printing something like a phone case it is much easier to design one that fits just right if you print with PLA rather than ABS.

Given the minimal shrinkage, lack of fumes, and no need for a heated bed you might be wondering why I’m even presenting a choice between ABS and PLA. PLA seems to be far superior in almost all respects. One factor to note, however, is it is far more finicky to print with. With PLA, if things are not perfect the printhead can become clogged. This is not a problem I’ve ever had with ABS.

I was so fed up with problems related to ABS that I’ve been printing exclusively with PLA for the last couple of years. For the 9 months, with my first generation Replicator, I have not been able to print something that takes more than an hour and a half before the print head jams. Often it jams much sooner. Newer printers may be more reliable, but I don’t have experience to speak to that. Yesterday I switched back to ABS and was able to do a two hour print of a comet and a five hour print of a fossil skull with no problems. For my printer I may switch over to mostly ABS and just print in PLA when I need something that fits precisely.

While I’m talking about Plastic I should mention that both types should be stored in sealed containers. Over time they will both absorb moisture and this could cause problems while printing. I use a container designed for long term storage of food and I toss in some silica gel to absorb moister. The container I use was less than $15 on Amazon and will hold two spools of plastic. The other bonus with using containers for storage is it will keep your plastic relatively dust free. If dust accumulates on the filament it can cause the print head to become clogged.

Go Back to earlier parts in the series: Part 1Part 4

Getting Started with 3D Printing – Jazz Hands

In my last post I walked you through creating a relatively simple cell phone holder in Tinkercad. In this one I want to show you how easy it is to modify an existing design. You can do this with your own models or you can do this with ones you find online in places like the Thingiverse.

We’re going to add a design to our phone case we made in the last post by importing an image in svg format. svg files can be imported, resized and extruded into 3D objects. I’m going to use a public domain image from Pixaby. I like Pixaby because all the images are public domain. They do have svg files available for download, however, I haven’t had any luck importing their svg files into Tinkercad. Instead I find an image (png or jpg) I like and convert it using the Online SVG Image Converter. You’ll want an image that is only black and white (literally black and white, not greyscale). If your image has any grays they will be treated as black when imported into Tinkercad. The image I chose has some grays, but I think it will look fine as black and white.

Basically you just import your svg file, resize it to fit, and the position it where you want it to go. You can either do this as a raised pattern or turn it into a hole and use it as a recessed pattern. You can find full directions in the Google Presentation below.

Go Back to earlier parts in the series: Part 1Part 3 or go on to Part 5

Getting Started with 3D Printing – Lets make something

OK, it’s been a couple of weeks since my last post. I’ve decided to do an instructional post to break things up a little. One of the projects I had my physics students work on last year was an engineering/design problem. I simply asked them to create an accessory for their cell phones. This idea was not original to me, but I honestly can’t remember where I got it from.


In order to actually make their own accessories my students needed some sort of program to create a 3D model. Our school doesn’t currently have drafting or CAD classes, so I was left with only a few options. We have no CAD software and even if we did, my students wouldn’t know how to use it.


I settled on cloud based solution, Tinkercad, for my students. Tinkercad is very simple, which also means it lacks many functions you’d expect in a traditional CAD program. It is also run in the cloud so it can be slow at times, but on the plus side if your computers have Chrome there is also nothing to install. This can be a huge plus in an educational environment. I use Tinkercad at least in part for almost all my 3D printing projects.


The basic idea behind Tinkercad involves building models by joining together simple shapes. Shapes can either be solids or holes. It seems like this would be a difficult way to create anything, but as it turns out you can create some very useful models with this very simple idea.

I originally found this phone stand on Thingiverse. I like it because it holds the phone up a little higher than most of the ones I’ve seen. I’ll show you how easy Tinkercad is to work with by recreating it. We’ll talk about the phone case in a future post.

If you have students create accounts for Tinkercad please steer them away from using their Facebook or Twitter accounts. In the past I’ve had a few students create accounts at home using their Facebook credentials. We block Facebook, so they were unable to access their accounts at school.



Go Back to earlier parts in the series: Part 1, Part 2, or go on to Part 4

Getting Started with 3D Printing – Part 2

This is part two in my ongoing series of articles on 3D printers for the classroom. Click here for part one.

I don’t know about you, but I have virtually no training in 3D modeling software. How should a classroom teacher start with their new 3D printer? Personally, when my printer arrived I spent a lot of time looking for cool designs online. The main repository I used and still use is the Thingiverse.1

The best way to start with your new printer is to find some models that other people have created and printed successfully and print them your self. There are lots of great ones to choose from. Some of which are simply models for demonstration while others may be tools or puzzles. My printer came with two spools of plastic. I burned through them and called it professional development. I really did learn a lot from this. You should probably do the same thing. Print stuff because you think it might be fun, useful, or you just want to see how it prints. I think the nerd word for this is experiential learning.

The bottom line is, it doesn’t really matter what you print. Print small stuff, big stuff, stuff with lots of small details, stuff with overhangs. Start with the default settings on your machine, then change them to see how it affects the final print. This will begin to give you a sense for what you can print and what you can’t. I also kept a small scale handy so I could determine the mass of my prints and then figure out the material costs. If I buy a 1 kg spool of plastic for $48, then each gram of plastic used is 4.8 cents. So a 20 gram part costs about $1 in materials.

Don’t worry if you’ll never use these early prints in your classes. One of the first things I ever printed was a replacement cup holder for my Ford Focus. While it had nothing to do with teaching it did begin to show me the power of having access to a 3D printer. I also got my first experience with warping2, a problem that plagued a lot of my early 3D printing.

During my learning process I did manage to print a few tools to be used for teaching, including a Macro Extension tube for my camera so I can take extreme closeups without having to buy a $400+ lens, an adapter to hold my iPhone to a telescope, an adapter for my Canon camera that works both with our telescope and our instructor microscope. But mostly I printed random stuff like an iPad sound reflector, games to play with my son, Higgs-Bosons, Pan Tail Duck call, and a bunch of other stuff.

If you feel you must print something useful try these:

  • Triangle “Missing Square” Puzzle: It’s a good critical thinking exercise. Print one and play. You may have to do a little sanding to make it fit perfectly.
  • Wind Puzzle: Not sure if this one is a Bernoulli effect demonstration or some other fluid dynamics principal. Either way it’s fun and my students love it.
  • Microscope Mount for iPhone 5: I modified an iPhone telescope adapter to work with our student microscopes. If it doesn’t fit yours I’ll teach you how to modify it in a future post.
  • One Small Step: Cool desk placard showing the first footstep on the moon on one side and the moon in relief on the reverse.
  • Lincoln Life Mask: The Smithsonian is starting to publish 3D models of their artifacts online. You can see how the presidency aged one of our greatest leaders.
  • Air Powered Rocket Car: This one presents good learning opportunities. It’s the first one I printed that required “supports”3.

Back to Part 1 or Continue to Part 3.

Footnotes:
1. Now I should say that many people have philosophical objections to the Thingiverse. Thingiverse was started by Makerbot. Makerbot had it’s origins in the Open Source Hardware movement. At some point Makerbot moved away from Open Source and was later bought by Stratasys, a large traditional 3D printing company. However you feel about Makerbot’s abandonment of Open Source or their later acquisition, the Thingiverse is a great place to find cool models to make.

2. Warping can happen with larger prints. The corners of the print lift off the build platform. Sometimes the part will still be usable, but more often it will not and sometimes can lead to the whole print coming unstuck resulting in a completely failed print job. I’ll talk about what to do to deal with warping in a future post.

3. FDM printers build from the bottom up. For some prints you will have parts that can not be printed because there is nothing below them to hold them up. Supports are typically a series of thin “walls” added below these areas, designed to be easily broken off the final print.

LED Color Mixer – Make and Take

Tomorrow, Saturday 10/4/14, is the fall meeting of the Michigan Section of the American Association of Physics Teachers. If you’re interested, it will be at the University of Michigan, Flint. For more information you should check out the meeting page.

Anyway, Jim Gell and I will be running a Make and Take in the afternoon. One of the things we will be doing again is the ever popular LED Color Mixer. We’ve done this before as a modified version of the LED mixer presented by Chris Chiaverina in the Physics Teacher. This is a pretty cheap demo device, but in the past we ordered $1-2 LED, $1 battery holder, $0.50 ping pong ball, and 2 AA batteries. Cost for each one was between $3 and $4. This was a bit costly to run as a Make and Take. It also involved soldering, which while not particularly difficult did require the direct supervision of someone.
We will be doing the same project on Saturday at a cost of less than $0.20/device with no soldering required. This project is cheap enough that you can have participants make one on site and then send them home with a couple extras to make with their classes. They’re so cheap that a teacher could have each of their students make one to take them home and explain how they work to their families.

The parts list:

I should note that while both the batteries and LEDs are sourced from Amazon, the LEDs come from China and will take a few weeks to arrive. While the LEDs are cheaper than we’ve been able to get them in the past the real savings is from the batteries. In order to make things extra cheap I replaced the ping pong ball with a paper cube.
Simply bend the leads on the LED as shown. The shorter of the two leads goes to the negative side of the battery with the longer going to the positive. Use a little electrical tape to hold the leads to the battery. If needed, slip a small strip of overhead transparency in between one lead and the battery to act as an “off switch”.
Print out a copy of the 2.25″ Cube Template and assemble. Before closing the last flap put 1/2 a Kleenex in to help diffuse the light and cut a hole in one side. The simply slip your LED and battery in and bask in the color changing goodness you have created.
How would you use this with your students? Share your thoughts in the comments.