To meet the project requirement of using a microcontroller, we decided to develop a giant Atmega328 with an Arduino embedded inside. This would be programmed to provide a jumper-selectable logic training application- various gates, latches, flip-flops, etc, as well as some combinatorial networks to be mapped out using K-maps or other methods. It would also have a zif socket to allow it to re-program stock Atmega328 parts in the field for use in student kits.

We also (naturally) opted to make a 555 timer IC.

The various methods we've tried have had differing levels of results. We used on of the CNC machines to cut a mold out of foam. We've tried vacuum forming as well. It seems that the most successful method is likely to be stacked layers of foamcore with a pocket carved out of the inside, and wire traced between layers back to the pocket. The chip itself can then be embedded inside or attached to a circuit board forming a substrate.

Two PCB-based scaled chips. Home etched circuit boards, for 8-pin devices. The pins are banana plugs pushed through the hole and screwed down. There is no cosmetic cover plate- this could be added, or it could be left bare to improve visibility.	The post-carving IC, top half. We made two halves so we could sandwich them around the works inside.
The innards of the Atmega328P model. Each pin wires up to the appropriate Arduino pin.	The completed Atmega328P, on the breadboard.

"Done" is a relative term- while we have a functional and complete system, the actual stable of parts is wildly expandable. For instance, if we decided to do a 10x build of a TV-B-Gone, that would necessitate a new set of components- a different microcontroller, infrared LEDs, some transistors and a few other things. An AM radio might require a crystal and an audio amplifier. A real masochist may try making a POV display, which has its own dramas.

At any rate, this is where we've elected to plant our flag- an assortment of LEDs, a pseudo-Atmega328P with an Arduino Deumilanove clone inside, a 555, resistors, capacitors, dipswitches, a pushbutton, a light sensitive resistor, and a rotary encoder. The whole thing can easily be driven off a 9V battery- our student kits are a breadboard mounted on a piece of coroplast along with the 9V and holder.

Jude swears he is going to make a furniture-grade board out of walnut.

One thing I want to point out: of the 11 or so people involved in this project, only maybe three of them are dedicated electronics hobbyists. The involvement we got from non-electronics members is something we're very proud of, and we certainly could never have done this without the whole cast of characters.

We will be showcasing this at the Science Museum of Minnesota's Make Day in two weeks- we're very excited to get the chance to let some more kids experience the 'A-ha' moment of their first living, breathing circuit.

Last of all, I asked for some input from our team members. Not all of them responded but here's what those who did had to say about their feelings on the project.

Pete:

I thought it was a great experience, I was surprised that the team working on the project remained fairly small, but pleased that any requests for help to TCMaker at large were extremely quick and very helpful. Maybe we need to look at how we internally market such projects and recruit members to be on this type of team.

What did you learn? 

I learned a ton, and am very grateful to everyone on the GHSC team for their support, and to TCMaker member and friends who shared their time and effort to make this a success. The new areas I got immersed in were casting and vacuum forming, both of which have been things I've wanted to do but never quite gotten to. I also was directed to OpenSCAD by a GHSC team member, and learned how to use it to make models for molds etc.

What went wrong?

Everything, that's how I learned so much. I had CNC problems, Peter was very accomdating and cut molds for us to keep things moving. Casting and Vacumm Forming take time to gain experience even with experienced guides, so it was the good kind of mistakes and learning.

We nominated Mike the Grand Poobah to be the final word on decisions, which I think was correct, but we should have done so sooner. The abillity to see and track the other entries was terrible, not something we can change ourselves, but should be mentioned to Element14. The tools didn't work for me multiple times. There wasn't a good means of challenge entry aggregation either, that seems like a huge missed opportunity.

What went right?

Casting LEDs went well, and we got reproducible if flawed components, Karin the component Queen took over making most of the other compents and turned out and amazing quantity and variety of items very quickly. I think the build process for how to layout and secure the components evloved with input from multiple fronts, but I wasn't sufficiently involved to know.

What would you do differently?

If given the chance, I'd try and clear my calendar a bit. I'm going through major housing rearrangement and renovations and that greatly curtailed my available time. Also, I feel we have the luxury to look at small issues, because everything went so well, my suggestions are:

I'd try to get more members involved early on.

I think having more upfront design sessions would be helpfull. On this project we could work pretty independantly, because we were scaling up discrete components for much of the time, we didn't need to meet and has out a lot of the parameters of what the result needed to do. (Take resistor, make it bigger to the correct scale, repeat) The only downside that we hit, and it's very minor is that we didn't have a consistent look and feel to things, I think that would have been helpfull to discuss early on. I think the impact of not doing so on another type of project could be much more harmful, and cause lost work due to incompatibility / lack of standardization.

Getting everyone to post about what they are doing, at least internally would be helpful so everyone is aware of what's going on, how many x have been made, did the last casting turn out, has anyone refilled the mold? What materials are we making x out of? why? what didn't work? and why? ( Process xyz to make a diode wasn't mechanically strong enough etc)

Will you do this again next year?

I'd certainly like to be involved again, it was great for me and my bonds with others at the HF.

Where do you see this project going?

That's hard to say, I have a limited imagination for such things. I think a lot will depend on how much exposure it gets, how well it resonates with other groups, and how growth and extension is coordinated. I.e. how does TCMaker sheppard the project going forward.

What excites you about it?

First, it's just intrinsically cool, you've gotta love giant components that work and can be used to build real circuits. I'm excited to see the reaction at Make Day at the SMM, and am very interested in the feedback of those seeing it for the first time there. I think the projects universallity and utillity is a huge plus. I think the abillity to build parts out of almost anything is also a huge plus. I had access to both knowledable people and parts to pursue my interest in electronics from an early age. I'm still learing 30 some years later, I think this project my give others who have less access to expertease a "way in" to electronics, and would definately facilitate group learning and experimentation in a great way.

Jude:

This project was cool before the contest and the contest only expanded the possibilities. When we first started working on the idea as an aid to our stuff I felt it was interesting and would be fun to work on. But when the challenge happened with its focus on education and its emphasis on the worldwide scope it really turned me on. It also perhaps diverted me. I tended from that point on to look mainly for widely found materials and easy construction techniques.

I could have worked out an exact upscale of the the board and strove to make components exact replicas. Instead I found myself looking for materials in the dumpster and ways kids could construct and get their hands dirty. The hand, head and heart connection in learning to work needs to have many entry points. That kids could make a resistor mock-up while learning what a resistor does and how it could be used broadens the opportunity to catch some kids heart. Informal learning can have a much more lasting impression then the less hands on formal process, and who knows just what will ensnare a kid.

That we have come up with multiple ways to get to each different component is I think a strength. That we have shown that the board can be constructed out of a wide variety of found materials is also a strength. Cardboard, Foam insulation. Soda cans, Poster board, White Board, Pegboard, Steel wool and all the other materials we found are available in some combination sufficient to construct the board literally everywhere in the world.

I will probably never forget the demo at our fair when the kid started building the circuit without me saying a word just by looking at the big board circuit. At that point I realized we had succeeded. What is more I realized that the board works both ways big to little and little to big. Much younger kids can use the big board even though they would have great difficulty with the small board and components.

The only thing that ever worried me is that this project is such a fundamental and simple idea that it would not be flashy enough. But after that young boy I don't care.

Great fun, great project.

Karin:

Coming into this project I had no knowledge of circuits, components, or electrical anything for that matter.  I built about 50 components and had an awesome time learning the basics.  There were of course prototypes and failures but that was just part of the fun of the whole process.  I liked having a box full of possible materials and being allowed to experiment.  I don’t really have any suggestions on what should be done differently because it all seemed to work out well.  I think I could have started earlier in the process if I had had a list of the different components that were needed and felt a little bit more comfortable jumping in…once I got my feet wet it wasn’t an issue continuing.  I would do this again in a heartbeat…no matter what topic it was!

I think our project has the potential to keep going as an educational tool for our organization but I hope for others as well.  I think the potential and purpose for this is what has me the most excited.  This is such a great tool for hands on learning that can be duplicated anywhere in the world and with limited financial resources.  In fact, this could really encourage creativity and the reuse and recycling of materials. Accessible education is imperative to so many in this world. I am very proud of being able to help produce something that could truly play a role in making this knowledge obtainable.

Mike:

As the project draws to a close I have to say the experience was everything I'd hoped it could be. It gave me a chance to meet and work with some of my fellow members that I hadn't worked with before. It was great to have a project with a deadline and a sense of purpose, something internally driven rather than imposed from without.

I'm very proud of our team, and I'm very proud of our project. I'm thrilled that of the members of our team, only a couple had strong knowledge of electronics coming into this. Most of the project didn't require a great deal of electronics knowledge, which meant that it was far more accessible to our general membership. It was an educational experience for everyone- most of us learned at least one new skill (vacuum forming, silicone mold casting, soldering, resistor color code reading, papier-mache, to name a few). A couple of our members got to use the CNC tools that they've worked so hard on "in anger", so to speak, for the first time. All of us had a great time.

I've said it before, and I'll say it again: all I hope for is that one kid somewhere gets that fixation for electronics that comes with the blinking LED moment, and that fixation makes that kid's life better.

Thanks to the team members!

Jude, Karin, Pete, Peter, Mike, Jon, Paul, John S, Scott, Wayne, Adam, John B, and anyone else I might have missed. You guys did a wonderful job and I'm proud to have worked with you.

Of course, lots of fun in electronics comes from other types of componets- light dependent resistors, magnetically activated reed relays, potentiometers, rotary encoders, pushbuttons, dip switches, and many others. We created a couple of those components for various circuits- we have some ideas for others. Below find some pictures and details of things related to these other components.

The photoresistor is a good example of just how quickly, easily, and cheaply a component can be made. This one was made out of three styrofoam plates fished out of the trash in the 10 minutes before people started showing up at our Minne-faire. It's not perfect but it is a fairly accurate representation of the component, and it WORKS!	Unpainted dip switch bank. As the switches slide back and forth, copper foil on the underside of the top plate connects with foil on the switch, making the connection. Jon and Karin put this together in perhaps an hour with scrap wood and cardboard from around the shop.
A nice view of the switches before they went under the cover plate. The copper foil on the crossbar of the "T" is clearly visible. Aluminum foil or cut up cans would be probable substitutes; we happened to have the copper foil on hand.	Pushbutton made by team members Jon and Karin. This one is charming in its simplicity as well- it's a cardboard box and a condiment cup. They get bonus points for reusing a box from Sparkfun!
The innards of the pushbutton. The wires are pressed against copper foil; steel wool forms a fairly compliant contact. The spring force comes from some coiled solid core wire and the bridging contact is more copper foil folded around the rim of the cup.	Rotary encoder in process. The shaft is a piece of the plastic tubing we used elsewhere for capacitor bodies; the end plugs are foam core that has been hotglued in. The shaft of the encoder is hotglued in as well. This will be placed in a box in much the same fashion as the pushbutton.

I will update this post if additional parts are completed in time- however, I think this shows a nice cross-section of what can be done cheaply and easily.

A few other things that might be fun to implement:

- 7 segment display

- buzzers (we do have a buzzer but it's fairly small)

- relays (a large homebrew that allows students to see how the switching mechanism works would be particularly appropriate)

- potentiometers (similar to the rotary encoder; may be a bit harder owing to the added torque that can be placed on it when it hits the limit)

- large toggle switches or push buttons (NKK SmartSwitches would be fun but expensive to use here)

Naturally, we must discuss the construction of the board itself. There are two aspects to the board- the grid itself and the connections behind the board.

Thus far, our resident board expert Jude has made two different board surfaces. The one on the left above was a piece of pegboard- we taped off some lines before painting it to provide visible demarcation between the halves of the board and the vertical columns down the side. The one on the right was far more labor intensive- Jude made a pattern from some pegboard and used it as a template to drill holes in a piece of whiteboard. That allows the instructor to make notes about the circuit easily.

The connections on the back side of the board have been the subject of much experimentation. The problem is simple- the conductive element must be cheap, easy to work, and durable. Durability ruled out aluminum foil. Cheapness ruled out copper foil. Easy to work ruled out steel sheet.

In the end, we found two methods that work, both involving the same insulating foam we used for other applications throughout the process, and both requiring a channel to be cut in the foam. The top piece in the picture above was the quick and dirty method- stuff the channel with steel wool. It works great, but it has a major flaw in the fact that a short circuit through the steel wool could easily cause the bundle of steel wool to catch fire, and the foam and wood construction of the rest of the piece is hardly fireproof.

The bottom piece was ultimately selected as the best-in-show- it's a folded piece of beverage can that has been slightly roughed with sand paper to expose bare metal. Over time, there may be some issues with oxide forming and preventing a good connection, but that's not likely to be a long term issue.

A final, equally valid solution: skip the busing entirely and make a discrete connection on the back of the board using alligator clips and wire, or any other desired method. This trades up front work for work before each class but it could be worth it if the methods presented here prove to be long-term reliability killers.

Also, note that there is nothing saying these solutions are the best- only that they are the ones we came up with after some trial and error.

Notes on component building with students (Contributed by team member Karin)

This design concept has the capacity to be utilized in an array of settings and situations, regardless of the age of the students or economic status of the school. It is highly versatile and reproducible. Most components could be produced by the students themselves, dependent on age-range; many materials could be used to match student skill-levels and available funding.

The instructor will have minimal prep time with the focus being on providing the students with a hands-on learning experience. Each child could be given the basic materials to construct their own resistor, capacitor, diode, etc.  During the process they could work on assembly of the interior structure, wrapping the wire around wooden dowels or thin wood scraps, basic soldering of the real component that will make it functional, and then bringing in the fun of adding a casing to the component. The casing is the most adaptable element of this project.  Materials could be paper mache, basic earthen clay, polymer clay, clayche, tubing, pipes, pop cans, foam, cardboard, masking tape, etc, the sky is the limit.  With institutions that have limited resources this can really open the door to
reusable resources such as used paper/shredding or refuse (cans, bottles, card board etc.) from the school or community.

This is a great activity for students who need a very tactile approach or possibly students with special needs such as ADD or *sensory integration issues and so on.  The deep pressure or “heavy work” of clay could help regulate a child after the intense concentration needed for soldering, thus finishing the lesson with a positive experience.

Another facet of the lesson could be a written assignment for homework that could go more in depth on what they just created.  If each child had a different resistor, they could research what each color represents, what the function that component is and the different applications that may be specific to that component type.  After completion of the written assignment, they could present to the class their component and give a brief lesson on what they learn and show off their finished product. The instructor could then go back and review the different types and then test the class on what they just learned.

Once the components are made, the instruction can continue into how each component works in forming a complete circuit.  The complexity or simplicity of instruction can be custom fit to the audience, time available, and desired outcome.

Overall this classroom project will cover fine motor development, hand-eye coordination, art, basic electronic knowledge, public speaking, writing skills, and problem solving.

Notes on using the Big Board in a classroom setting (Contributed by team member Mike)

Having taught a number of beginning level electronics classes, I understand well the difficulty in getting students past the dull parts of the topic (Voltages are plus and minus labeled thus; current is this little arrow. This is a battery, this is a resistor.) to the exciting parts (OMG my light is blinking I did it!!!). Those of us with some years of experience behind us have likely forgetten what it is like to look at a schematic and see nothing but cryptic squiggles and bizarre pictographs. An analogy I like to use with prospective instructors is to try and get them to imagine what it is like to visit a country with an alphabet significantly different to your own (for Westerners, and nation where Arabic is the dominant script is a good example): not only do you not know what the written messages are trying to convey, you can't even parse them as written messages, and you feel overwhelmed!

The Big Board is effectively a way for students to get to the good parts of the story without having to learn the alphabet first. By teaching the mechanics of the breadboard (horizontal rows connect thus, and columns thus, for instance), and teaching basic assembly practices (don't let bare wires touch each other, etc) through hands-on creation of functional circuits, students learn an intuitive sense of what they are doing and get very instant rewards for their efforts. Once the circuit constructed, an instructor can bring out the schematic and tie the various physical sections of the complete circuit to the conceptual areas of the circuit diagram.

As the class progresses, other instructional possibilities become available. The instructor can pre-build a circuit before class begins and ask students to draw out the schematic, and figure out what the circuit does based on that. A programmable device can be added (more on this later) which simulates various functions of digital circuitry (logic gates, adders, ALU functionality, registers, combinatorial circuits, etc), and the students can be provided with a smaller version of the instructor's circuit and asked to reverse-engineer the "black box" and figure out what's inside. Difficult topics such as race conditions and switch bounce can be demonstrated in a macro scale in front of the whole class, on a device programmed to produce such glitches more readily than it might otherwise do. In a more advance setting, say a college electronics lab, non-functional versions can be wired up at the front of the room to allow students to more quickly create the circuit to be used in the day's lab project (the point of those classes being more to teach about what a circuit does than how to build on a breadboard, and the instructor's time being limited).

I tried posting a few days ago, and the site was having lots of problems, so I posted to the TCMaker site instead. I just updated that initial post with some more pictures from the last few days, Vacumm forming went pretty well,

the RTV molds we made seem pretty good,

but the resin casting has been more challenging. I couldn't get the mold center piece to let go.

..... Sorry the server is screwing up again, check the blog link below for the details.

You can see the post with update and all the pictures, on the TCMaker Blog.

Pete

We exhibited the 10x breadboard at the Maker Faire on Saturday, and we had a number of kids stop by and duplicate the example circuit on a more modest sized breadboard.

We had a working 10x optical theremin, and the parts to build a smaller version. It was a big hit with adults and kids alike!

I'm going to see if I can find some pictures or video to post of the event- I saw many people taking photos but I haven't seen any yet.

There's our single step- a super-scale LED being lit up through a 10x resolution breadboard.

We've been pondering and tinkering, trying to find the best technologies and methods for making our kit.

We anticipate that the first kit will be a "Cadillac" of sorts- good looking, highly functional, but not cheap. Along the way, though, we're finding things that work (and things that DON'T work) to make much less expensive versions, out of much more available components.

A good example is the LED above. It's made of nylon rod that was rounded down by hand (I think a wood lathe may have been involved). That's a reasonably cheap, reasonably easy way to make it. A second pass was based on hot plastic forming- a pyrex test tube was heated and pushed through a flattened gallon milk container (probably composed of LDPE). It stretched nicely over the test tube, creating a 1" dome (which is slightly smaller than 10x for a 3mm LED). Today, I'll be making a positive to try some resin casting and see how that works.

By the end, we hope to have one really swanky kit that is durable, portable, and reproducible, along with a large volume of information about methods that will be cheaper at the expense of durability and looks, perhaps, or that will take less money but more time- up to and including directions for making devices out of parts that can be scavenged in basically any trash heap anywhere in the world (with the exception, perhaps, of the actual electronics).