More about 3D

School is back in session and the one thing that almost everyone is coming by to look at are the 3D printers. There have been a myriad of questions

1. How does it print?
2. Where is the plastic coming from?
3. What are you going to use it for?

All of the questions and comments have been positive but I have found the most intersting one to be "What are you going to use it for?" or "What will you print with it?" Hmm  - I had the same question when we were first approached. As you think through it the question becomes "What can you not use it for?" As things come up during the day we begin to realize that a solution would be to design our own part for it. An example is the Raspberry Pi - we have been working on powering LED's and controlling them with it but now we can Print our own small houses, parts, letters and create holes to hold the LED's to make them light up. We can add parts to our LEGO robotics designs, we can build anything! 

So now on the third day back at school I already have students who come in and say that they have downloaded something from Sketchup Warehouse and would like to print it. We are accommodating this for now because we want to make mistakes and have some things print well and others not. This is happening. Below is a picture of a Star Wars fighter that was downloaded from the Sketchup warehouse - it did not print properly. As we have already found with our own simple designs there seems to be a problem with the faces and unless there are all facing the right way the model will not print properly.

Lessons learned - 

• It takes a long time to print - 4 hours + for many things
• It is difficult to remove the objects from the blue taped platen  - we bought some plastic putty knives and they are doing the trick. We have to remove the platen then kind of chisel it.
• The platen needs to be leveled after several removals 

The printers are amazing and have been in use at least 8 hours a day for the last 3 days. 

3D Printers 2

We have been tinkering with the printers and software for a couple of days and although we still do not have kids on campus (December Holiday Vacation) we have made a few discoveries. I'm sure there will be many more to come

Sketchup -

1. You need to download a .stl exporter - this is the right language for the MakerBot software to print. This exporter is found in the "extensions warehouse" within the sketchup program. Note that I found that I had to sign in to download the extension.
2. Once you create something in sketchup (and believe me anything I have made in very simple) I found that if I selected it all and "grouped" it that worked well before I exported.
3. Faces and facing the right direction - this has been tricky and has been the subject of some inline discussions. When we thought everything looked perfect and exported it to .stl then into the MakerWare software it looked great. When we printed it look much different than the model. What we found is that the "faces" of the objects created in Sketchup were not facing the right way. If when you look at the structure in either Sketchup of Makerware, you find that one of them is dark (and it seem logical that it should be light color) then it needs to be turned around. This is better described in this blog - http://www.makerbot.com/blog/2011/07/22/google-sketchup-design-tip-fix-flipped-faces/

The MakerBot 2 Printer

1. Printing from the computer - When we first printed using the MakerWare from the computer, the computer tried to logout (network setup in school) and paused the printing and we could not resume it. We solved this by unbinding the computer from the network and now it does not disconnect or sleep. The OTHER solution was to "Make" to the supplied SD card and then plug it back into the printer.
2. Sticking to the blue tape - The first object was fairly easy to remove but since then we have had trouble getting the objects off the tape. We have not arrived at a solution yet but are working on one. 

3D Printers

Wow! We were fortunate enough to receive a donation of 2-3D makerbot printers. We decided on the Makerbot 2 instead of the 2x after finding that the 2X was reported to be slightly more finicky. We chose to purchase them at the Microsoft Store so that in the event of issues we might have some  local support.

Two New MakerBot 2's

We started off carefully, even going so far as to watch the youTube video of how to unpack your Makerbot - not sure that was necessary but it was a new toy and we certainly didn't want to damage it. The setup was straightforward and we found the setup video helpful.

Included with the machine was an SD card with pre-loaded things to make. This gives one the instant  gratification of being able to make something right away - we selected the comb. Amazing! We could not believe the accuracy of the machine. It did take some time and after the first minute of watching the printer we decided to go through a few steps required for us to be able to design and print from the computer (Apple mac).

We first found that we needed the makerware software. This software is a kind of translator/scaler/viewer and the last step required to talk to the 3D printer. We decided to use Sketchup to create our models. This proved to be slightly more complicated than we had thought but more on that later. Below are a couple of pictures of the printers.

The Initial Leveling Porcess

Made Our First Letter

Head of School Showing First Project

Downloaded file

Connected Classroom - Google

Yesterday I went to the New York Hall of Science to watch a few chemistry experiments. I didn't actually go but rather I sat at my computer and watched as a live demonstration was given via the Connected Classroom. Yet another tool that Google has designed to help teachers and of later take over the world :). This is the first of many of these trips I hope to take and which I also hope to share with all the incredible teachers we have here at Harbor Day School.

Electrical issues

The students have really done a good job connecting the relays to the various LEDs via the breadboard. We are now working to connect some LED lights that I ordered online. The first mistake was ordering plug in LEDs that require 110V AC power. I decided that ordering the nice battery powered lights was the best idea.  Unfortunately most of the lights have a controller with 3 or 4 wires which allows them to blink in various patterns.  We have spent 2 full class periods finding out how to get the lights to turn on using the relays and power supplies. We found that one of the LED strips needs 25 volts to operate and because it has 3 wires we had to find out how to get the various sections to light as a function of the wires that were powered.
We finally have some lights working with regularity and are now going to program them. The kids are doing well but I think it's time to define some tasks and set some goals - enough tinkering.

Grit

As we work to have students learn about perseverance our school has made an effort to have students not give up easily when they do not understand something. The programming and assembly required for this Raspberry Pi project certainly makes student work. An example is the student who work tirelessly to get his LED blinking. He had little trouble setting up the Raspberry Pi, loading the OS and connecting the peripherals but when it came to connecting the LED it was not as easy (this was true for everyone).
   There are essentially two components to this connection. 1) you need to write a Python program to control the GPIO ports on the Pi and 2) you need to properly connect the GPIO pins to the breadboard and LED.

He entered the program into the Python shell and connected the Pi to the breadboard. When he ran the program nothing happened - no blinking just lighting. He reviewed the program, he watched the video on how to connect it, he asked me for help and I suggested that the rewrite the program. Still, it did not work. We looked at the connections and it looked correct - well it wasn't. It took three class periods to figure it out but he was successful. I was impressed by his effort and he was excited about his success.  It seems obvious that problems like this and the other typical programming problems allow for repeated failure followed by success thereby demonstrating that sometimes you have to work hard, fail, repeat -- to succeed.

The LED's start

It is basically the 4th day and all of them have their LED connected to the breadboard and working. They are using Python to control the GPIO and should soon be able to write and modify the simple programs provided in the videos to better control the lights.

I have to say that the Youtube instruction is amazing - they were able to get to this point quickly. The next step is to have each student create a project goal. I will give them a day or so to play around then they have to come up with a project that they plan on making. As mentioned in another post they can work on the lighting program but they will still need to document it on their project plan.