User testing - round 2

I took my Little Boards to a friends birthday party last night. He has two boys, aged five and seven. And I was there with Adam, who's five in 7 weeks.

After dinner I opened up the box of Boards and stepped back.

Here's what I observed:

• the other kids, who had been play with Lego, were instantly interested
• Adam helped connect the power box and switches to make stuff go
• The 5 years old said "oh - these connectors are like the ones for a computer" and then proceeded to start connecting things together.
• The 7 year old said "Did you make these?" I said yes. Then he asked "Even the electronic bits?" Again I said yes. He replied "You're clever." I quite enjoyed that moment.
• Having a switch on the power box is confusing - I'll definitely remove that switch. You can still unplug the battery to kill the power.
• They wanted to plug every output Board in a string to see everything going. Unfortunately the 9V battery wasn't able to drive a motor and fan in series. We managed to find a big 10Amphour 12 volt battery though - which made all the Boards run fine, but also meant the power regulator heatsink got hot enough to burn fingers. And it meant the power board was tethered to a battery the boys couldn't move around.
• Once we had everything connected up, including the 12 LED Board, they closed the curtains and  turned the lights off to better appreciate the LED's. Everyone loves colour LEDs!
• Then the 7 year old said "Oh! These are big Lego blocks. I know... we've got some more, I'll go get them." So then we had a big box of Duplo that caused Adam to quickly build up a rescue vehicle with the LED block. The other's were suggesting other ideas too.

Sadly - that's when I had to wind things up so I could get Adam him home to bed.

I need to build power power Boards so that several kids can build projects at once.

I should build a "rescue vehicle flashing lights" Board for Adam.

How many wires?

The littleBits system which has inspired my project uses three wires; Ground, +5volts and signal (which can be anywhere between Ground and +5volts.

On each littleBoard there's an op-amp chip that has "signal" as it's input. The op-amp then provides power to an output device. This separation of input signal from output power allows for the signal voltage level to remain unmolested by whatever might happen on the output side of the circuit.

What does not happen

There are two other ways they could have gone with the design; two wires, or fully digital.

In a two wire system you start off with one Ground wire and one power line(+5volts max) coming out of the power board, and the input boards simply control the level on the power line between 0volts and 5 volts. The most common input board would be a simple on/off switch.

When the the switch is closed (on) the power line gets the full 5 volts. When it's open (off) the "power" wire gets no volts. Thus the output device either gets power or it doesn't. This is roughly how your standard light switch works; power, or no power.

In a fully digital system you'd run three wires; ground, +5 volts and signal. The signal wire would have serial data running along it to communicate between microprocessors on every board.

This setup has the full benefit of having the potential for all the bits to be programmed to do amazing things. The downside is it's inherently complex from from my 4 year olds perpective. It can be made to look simple to users, but - under the hood - it's not.

Which way should I go?

Initially I thought I'd slap together some simplified version of littleBits, then evolve to follow their three wire setup with op-amps on every board. But, now I'm toying with the idea of devolving to the simpler two wire setup. Or maybe stay with my initial hybrid three wire but no op-amp approach.

There seems to be plently of scope for building things with either way.

I built a fan Board, plus some pedagogical musings

Here's my latest Board - built from a fan pulled out of a dead computer power supply.

Fan Board with "long" cable. 

I left the USB cable full length this time to see how that works for Adam.

It's a 12 volt fan running from only 5 volts so it doesn't have enough power to hurt if you stick your fingers in to. And... of course there's an LED on there too.

I was hoping to find a smaller fan that would fit properly onto a block - but this is all I had in my junk box.

Pedagogy

My wife is a teacher and therefore is interested how these Little Boards relate to existing ideas around teaching and learning. What ideas can these help to teach? What is Adam learning when he's using them?

Here's some random thoughts:

• A switch is used to turn things on - just like a light switch, TV switch, many toys etc
• A battery (ie power) is needed - like in many toys
• Creativity is required to assemble/construct a project from individual bits/Boards/components. 
• You can develop an understanding of what each Board does as you are building something. You do not need to understand the basics before starting - but it helps to have someone handy to explain why it doesn't work.
• You can learn a lot when it doesn't work.
• Because Little Boards are glued on to Lego Duplo they come with a strong implication of being used with other Duplo blocks.
• The circuit is not the goal. A creative something is the goal, of which Little Boards are one part.
• It's fun to just watch outputs (LED's, propellers, fans etc).
• By piggybacking onto Duplo my Little Boards have co-opted some of the creative habitat that a child uses Duplo in - often all over the floor.

She also wondered how they are different from things like "BrainBox" electronic kits.  

• Electronic kits come with a book full of interesting circuits to build. The implication is that your goal will be to build one of the prescribed goals.
• Little Boards are more open ended.
• BrainBox type kits define the "build space" to be on the base board provided.
• My wife observed Adam build a BrainBox siren circuit (with help) at Playcenter and then take it out onto a trike in the playground. Clearly a child can quite happily take a BrainBox and "run with it" outside the context in which it was built.

One of the interesting things I like about the littleBits promotion is the emphasis on using the Bits with all sorts of craft materials to make things that contain littleBits. They're trying to add electronic boards into the notion of "making crafty stuff" with/by kids - along with cardboard, sellotape, straws, felt pens, etc. This is a powerful appropriation.

Branch Board

Tonights Little Board is a simple "branch" board: one input plug leads to three output sockets. Plus there's an LED on there to show power is available.

One in and three out "branch" Board.

Driving three output Boards from one power Board and one switch Board.

A few more boards: battery Board, switch Board and 12 LED's Board

I've made up a few more boards.

The current circuit designs are the absolute simplest possible - all the switch is doing is turning on/off +5 volts. The littleBits is more sophisticated than that - they're using the signal line to turn off/on the output of a  transistor (actually a an op-amp) which then drives the "output" Bits.

I'm going to keep building along my current track till I run out of things that Adam likes playing with - then maybe change over to some kind of transistor switching system. littleBits are using a LV321 which I can't seem to source from my local Jaycar store so I might using something else.

Anyway, here's what I've built since the last update:

Battery holder on a block. This allows for a much tidier construction.

New three position switch with LEDs. Middle = off, Right = on, Left = momentary on.

Red LED on left is always on when power is connected. Green LED on middle/right is on when switch is on. (I should have positioned it to the far right of the board next to the output end.)

LED output block. Just on or off.

All together. You can never have too many LEDs according to Adam.

At this stage I've noticed a few things:

It is very tempting to think about much more elaborate Blocks. I've seen on the littleBits suggestion forum people asking for Arduino Bits. I think this misses the point of the littleBits idea: simple little Bits. Arduino is small but not simple - in the sense that a 5 year old can understand how littleBits work and what each bit does - but an Arduino is pretty much a magic box for a 5 years old.

Using these things is much more engaging when used in the context of a wider creative ecosystem, ie lego or cardboard and sellotape.

Cheers, Paul

User testing

I spent the day with Adam today. I showed him the first three Little Boards (DIY littleBits) I'd made after breakfast and he spent most of the morning playing with them. During that time I built up another motor board - this one with the motor facing forward, like an aeroplane. After lunch we did some other stuff then he went back to the Little Boards and Duplo for another hour. And after dinner he played with them some more.

Here's the new motor board (below). This one has three LED's from an old AT keyboard. Adam loves LED's. I've also cut off the top lugs off the Duplo block so the end result has a lower profile.

New Little Board with forward facing motor and propeller, plus 3 LEDs. The propeller is a bit too stiff so I've added some tape to make the tips less dangerous.

One lesson learned from watching Adam is the USB tail cable has to be long enough to allow two boards to be mounted side by side. My first motor Board had a very short cable which I've now replaced. About 95mm of flexible cable is ideal.

By the end of the day we'd run our 9V battery flat so we switched to the more cumbersome 12V gel battery.

Here's the last thing he built before heading off to bed:

Twin motor  construction.

Adam loves LEDs so much I'm thinking of adding them to every board, even the simple switch Board. LEDs are great for trouble shooting connection problems.

All in all - a good first play.

Here's another creation from later in the day - this time with "super wings"!

Cheers, Paul

PS. The next day Adam had a friend 'round who also played with the Boards. His mother was quite worried about the potential for injury from the spinning propeller blades, so I stuck on some self-adhesive spongy foam left over from draft stopping around the doors and windows. It worked perfectly.

Little Boards - my DIY littleBits

I've started building some of my own DIY littleBits.

The first three Little Boards glued on to Duplo blocks.

For those who haven't seen them littleBits are small, very simple electronic boards that you can connect together to make simple stuff. They feature:

• small size about 2.5cm square (1 inch square)
• each one has a single very simple function (switch, wire, power, LED, etc)
• very easy connectors that snap together by magnets
• low voltage (so not dangerous)
• the electronics are exposed (cool)
• well designed and made
• attractive colour scheme
• US$10-15 each or US$89 for a starter pack of 10 "Bits"

Adam's "flux capacitor" made from an old battey drill,
cpu fan and large  LEDs.

My son Adam is almost 5 years old. Over the last few months we've been playing with fans and motors and LED's. This play usually involves us spreading out a box of bits and pieces on the table and having a discussion about what we could do with them. Once we have an idea, I connect it up for him.

With littleBits he would be able to connect things up himself. That would be much cooler.

Given that we both enjoy making things, and I've got lots of junk to play with - I thought I'd make my own littleBits, which I'm calling Little Boards.

Note: this is probably not going to be cheaper than buying littleBits. And I'm a complete amateur electronics nerd so some of the stuff I talk about here is going to be just wrong. But you might find some interesting ideas to steal.


Progress so far


I've built a power board, a switch board and a motor board. And I've settled on USB connectors.


Power Board v0.1

Permalink

Little Power Board version 0.1. Outputs 5v DC. Stuck on a Duplo block.

The power board is a rough copy of the littleBits power Bit. I've built mine on VERO board - so it looks a bit ugly - but seems to work fine.


I've chosen to use USB Type A connectors as my interconnection "system". That's because I've got lots of spare USB cables I can use and they are pretty good connectors. The littleBits magnetic connectors are much better, but I can't get those, or anything like them - and can't think of an easy way to make my own.


The littleBits system is based on 5V DC with 3 wires; 0V, 5V and signal. Note - it's an analog system. The signal line is not a serial data stream, it's just a wire with anything from 0 to 5V DC. I'm copying that setup. I think that simplicity is a good thing for this project.


The first time I tried this with my son he wasn't able to un-plug the USB connector - it was held in too tightly. I managed to solve that by bending the clamping prongs at the top and bottom of the USB Type A socket out. Now they're not too tight and not too loose.


I'm using:

• Pin 1 (red wire) = 5V
• Pin 2 (white wire) = signal
• Pin 3 (green wire) = not used
• Pin 4 (black wire) = 0V

I don't plan on using the Green wire at this stage.


I'm using a USB Type 1 socket as the output for each Little Board. All but the power boards will have a USB plug cable "tail" as their input end.


The power Board is a simple 5V regulator which can take an input of 6-12volts and outputs 5V. I've got a 2.5mm DC socket feeding the power into the board so I can switch from a 9V battery, a small 12V GEL battery, a 6xAA battery holder, or a 12V solar panel.


I could also power the Little Boards via USB charger or a 4xAA battery holder without a voltage regulator.


My boards are about 30mm wide and of various lengths; 45mm to 65mm. (This width provides 10 lines of conducting track on the VERO board.)


By a happy piece of unplanned design the 30mm x 45mm Boards I've built so far have a slightly smaller footprint than a 2x8 block of Duplo. So I've glued them on to Duplo blocks to give them a larger contruction/play ecosystem/context.


I plan to always stick power Boards onto red Duplo block (although it would be better to use half hight blocks and cut/grind off the top "cups"). I'll use green Duplo blocks for "input" Boards and blue Duplo blocks for "output" Boards. Other connector Boards can go on yellow Duplo blocks.

littleBits use a different colour scheme but I prefer my R G B system.



Rocker Switch Board v0.1

Little Switch Board.

This a simple on/off rocker switch that I pulled out of a hair drier.

All it does is connect the signal line to the 5V line.


Motor Board v0.1

Little Motor Board.

This is a small motor that I pulled out of a CD/DVD player. The CD tray had three motors in it - cool!

Plus there's an LEDs on it.

They are just connected between 0V and signal lines. So for the motor to go there needs to be a switch Board before it in the string.


Play so far

We cut out circles of paper and glued them on to the end of the motor (which has a small pulley guide on the end of the shaft). Then we started the motor and used felt pens to create patterns on the spinning disk. We observed how the different colours combined when the motor was spinning. Adam drew on the disk when it was stopped then turned it on to see what would happen. (Mixing colours and changing shapes.)

One of the other CD player motors had a pulley wheel that had a larger diameter than the motor so Adam was using that as a "grinder".


Little Board ideas to build

Power sources: USB direct?, 4xAA batteries direct. 12V Gel battery connector. 12V PV panel connector. Cellphone batteries?

Input Boards: slide switch, lever switch, slide potentiometer ("dimmer"), rotary potentiometer ("dimmer"), light sensor switch (based on garden PV light), timer delay (using 555 timer with pot), momentary ON or OFF switch, magnetic reed switch, pull cord switch (source?!), On/Off/On slide switch to two outputs (from hair drier).

Output Boards: motor, motor with gears and CD/DVD tray, buzzer from old cellphone, LED (red, green, blue, orange, white). RGB LED with three inputs. 5 par bar graph, flashing LED's,

Wire/Connector Boards: USB extension cords (1m and shorter), branch boards with 2 or three outputs, logic Boards (AND, OR, NAND, NOR, NOT)

I'm going to try building one Little Board every spare night I have. I'll keep you posted on progress.

I'll add photos, circuit diagrams and parts lists tonight.

Cheers, Paul