Saturday 18 August 2012

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.






Sunday 12 August 2012

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.




Thursday 2 August 2012

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.

Wednesday 1 August 2012

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