3D printer

Hello everyone! First of all, I wanted to share with you some notes regarding the latest updates made in the website:

• More information, a video and pictures have been added to ArduSkyBot 2012 Summer Workshop
• The page Robotics Introductory Course with the HKTR-9000 printbot has been created. It summarizes all the information (with a video and some pictures) and contains all the resources that were used in the course at Universidad Autónoma de Madrid in May 2012.

Next, here is "Micro", the latest member of the family! It is a Printrbot Jr:

Micro is performing very well. The main difference with the other printers is that it is possible to have it the desk, since it is so compact and quiet. It also has quite a small printing volume (~14x11x8.3cm), but this is not a problem as all and the prints have a good quality. It is also the cheapest printer I've ever seen. Definetely recommended. More pictures of Micro can be found in this album.

This new little printer has been the main reason to stop using the Printrbot "Lucy", which now needs some fixes (since it has been disconnected since Summer).

Finally, you may have seen the printable caterpillar tracks:

They are based on Caterpillator by Olalla, and on the Stretchy Bracelet and Moon Rover by emmett. Single-printed tracks have proved to work very well. I have used PLA from RepRapWorld, which is flexible enough for this purpose. Here you can see a demo video of the first version.

Thanks to the power of the community, a few days later after they were published, Jason Welsh released his own (and improved) derivative: the Arduino Book Case (Tank Tracks Mod).

The main limitation of the *SkyBot family of printbots has been that their wheels behave poorly in rough terrain. Since this new design doesn't require a complex assembly for the tracks, it is easier to get printbots replicated. This concept will be the base of our next robot design for testing swarm algorithms at the GNB-UAM.

I know, I know. You are missing the next part of the Printrbot tutorial. I truly apologize. It has been a long time. In the end, it will consist in pictures of the assembly process and some tips. Expect this to be posted in the next two weeks.

Of course, I will appreciate and answer any question you post in the comments (personally I prefer this method rather than email, also remember you can write in english or in spanish).

I have presented my first publication at ICERI 2012 (5th International Conference of Education, Research and Innovation), which took place the 19-21 November 2012 in Madrid (Spain).

The title is "Low cost educational platform for robotics, using open-source 3D printers and open-source hardware" and it is a collaborative work with Dr. Juan González Gómez.

Abstract

In this paper, we present a new design methodology for educational robotic platforms. Using printbots (open-source 3D-printable robots) as a starting point in our designs has allowed us to create custom robots with very little effort. Using this new methodology we have designed the ArduSkybot, a robot that has enough features for its usage at different educational levels while keeping a very reduced cost. The robot is based on Arduino and the Printshield, our new electronics platform. It provides integration of various sensors (light, distance and line sensors) and actuators (motors, lights and speaker). It is also easy to expand by students and researchers. We describe our designs, and document their performance in various workshops with college, primary and secondary students. Our methodology is described and suggestions are given regarding future printbot-based workshops.

About ICERI 2012

Attending the conference has been a very interesting experience. Meeting people from all over the world has let me see different methodologies and problems that I hadn't realised before.

For instance, have you ever thought on taking 3D printing technology to Nigeria? It was one of the questions that was made. For us 3D printing is a low cost technology, but we need to think how we can bring these kind of technologies into developing countries.

Links

• ArduSkyBot v2.0 printbot (more documentation)
• RepRap project (replicating low cost 3D printers)
• HKTR-9000 printbot (design and resources)
• ICERI 2012
• This publication can be also found in Juan's website (http://www.iearobotics.com/wiki/index.php?title=Paper:2012-11-17-ICERI-Printbots) and in IATED library (http://library.iated.org/view/GARCIASAURA2012LOW)

Resources

Following the open-source philosophy that has made possible this work, here are the paper and presentation (all Creative Commons BY-SA):

• Publication (PDF, DOC)
• Presentation slides (PDF, ODP)

Paper reference

Carlos García-Saura, Juan González-Gómez (2012) "Low cost educational platform for robotics, using open-source 3D printers and open-source hardware", ICERI2012 Proceedings, pp. 2699-2706. ISBN: 978-84-616-0763-1

This is the first part of a tutorial on building a DIY 3D printer. The model I have chosen is a member of the Printrbot family, since it is probably the most compact, simple and cheap desing out there 

Mine is called "Lucy", this guide will be based on it, here is a picture:

You can find the main details of this design in these websites:

• http://reprap.org/wiki/Printrbot
• http://printrbot.com/
• http://reprap.org/wiki/Wallace (This is a very similar design)

I encourage you to check those links out. Also, you should get an overview of other open-hardware 3D printer designs, if you haven't already done so. For example, my other 3D printer is a "Prusa Mendel" 

The original Printrbot design is nice, but we will be using some modifications to make it even more convenient to build.

Differences with the original Printrbot design:

• Everything is measured using metric units instead of imperial, so it is easier to get hardware parts in the EU.
• It has a bigger build volume: XYZ 20x20x21cm (Z expandable) VS the original 16x16x20cm (aproximately)
• It uses M8 rods and LM8UU linear bearings.
• I have found the Printrstand to be essential for the stability of the printer.

OK, now we have cleared that, let's get started!

Bill of materials: (last updated: July 2nd, 2012)

First of all, here is a list of all the required parts (with the suppliers I got them from), to get a rough estimation of the costs:

• Electronics & motors:

• Mechanics:

Screws, nuts and washers (detail):

Note: Cheaper screws are usually flathead, those are OK. If you can't find the exact length, simply choose the next longer one available.

• Tools (Free?):
  • Two wrenches (hexagonal for M8 nuts)
  • Screwdrivers
  • Pliers
  • Scissors
  • Cutter/modeling knife
  • Soldering iron (small tip) and tin.
  • Digital caliper (you can find it in eBay for like 10€, I consider it free as it is a tool).

So, you could theoretically build this 3D printer for around 395€ 

Note: If you finally order from http://reprapworld.com/ remember to buy some 3mm plastic filament. Your 3D printer wouldn't be very useful without ink  I would say 1kg of PLA and 1kg of ABS plastic of different colors is a good start. http://www.faberdashery.co.uk/ has a large variety of PLA colors.

Now go ahead and buy everything you need. Some parts will take one or two weeks to arrive ordering them online, but the highlighted ones can be found on any hardware store.

Rod sizes:

You must cut the steel rods into these pieces. Maybe your supplier can do that for you:

• Threaded rods:
  • 4x 32cm for the base
  • 2x 25cm for the Z axis (if they are longer you can print taller, with this you get around 21cm)
  • 1x 40mm for mounting the idler bearing on the X carriage
• Smooth rods:
  • 2x 31cm for the Y axis
  • 2x 35cm for the Z axis (same note: longer rod -> taller prints)
  • 2x 33cm for the X axis (try to be very precise with both having same lenght)
  • 1x 2cm for mounting one bearing on the extruder

This will give you a printer with the same size as mine, though you could make a bigger printer scaling parts as required.

Next part: Main assembly (pending)