This is a redevelopment of 2017 Christmas Tree

Developed Mick, Nov 2022. Revised for delivery in 2023.

At its heart the original Tabletop Christmas Trees was a very basic workshop with equal parts electronics and laser activity. And that's being generous - participants didn't get to use the laser (they got a demo) and the electronics was limited to a coin cell battery, wire and an LED. But it served as quick (20min) , entry-level introduction to people who'd never played with these ideas.

As the basis for a 4 hour workshop there would need to cover more.

In 2022 this workshop was scheduled in our Christmas program alongside Laser cut earrings and Laser-cut paper craft, so I thought it would be good to move away from the laser (which we were well and truly covering in the other workshops) and lean into the electronics.

As such, the workshop will focus on the following basic skills and understanding:

• Demo of the Laser Cutter and what you can do with it
• Electronic circuits - current flow and components
• Intro to soldering and the tools on the bench
• Intro to Microcontrollers with the Arduino Nano
• Intro to Coding for Microcontrollers using Arduino IDE

We acknowledge Aboriginal and Torres Strait Islander peoples and their continuing connection to land and as custodians of stories for millennia. We respectfully acknowledge the land on which we all meet today, and pay our respects to elders past, present and emerging.

In this workshop participants see how they can use a variety of tools in the Fabrication Lab to create an ornament illuminated with programmable LEDs.

We'll see how you can use the laser cutter to cut and etch acrylic to create a side lit effect and design and assemble an attractive 3D ornament out of a 2D material.

We'll learn the basics of how electricity flows and the different functions of basic components.

We'll learn how to use a soldering iron and some of the other tools on the electronics bench.

We'll learn about microcontrollers and how to use Arduino IDE to program the Arduino to create different lighting effects on our Christmas tree.

And if we have time, we'll customise our ornament with a laser-etched inscription.

If your workshop does not require any materials (maybe digital only) delete this section or change to something more appropriate.

Before the workshop you will need to …

see summary and show off what we are going to make.

Whats a neopixel - this is a gang of 4 x 4 = this means there is 16 cells but each Cell has a RG and B LED. and each of these has an individual address. and a little IC

and show them…

battery to usb power »>

5v positive into the arduino to power the arduino and power the all the LEDs (neopixels )»>

little computer script that we'll upload to the arduino will say which led will turn on when for how long in different patterns.

and when we fire it arduino and it runs our scipt it

10 mins

Activity - Assembling laser cut components

1. remove protective paper,
2. test assemble,
3. work holding,
4. Apply adhesive.

30 Min

An electric current is a stream of charged particles, such as electrons or ions, moving through a circuit.

Current is measured in Amps and symbolised as i)

*One ampere is equal to 6.241509074×1018 electrons worth of charge moving past a point per second.

Voltage, the electric pressure or difference in potential that causes this current to flow (conventionally from positive to negative*).

There are a couple of analogies that commonly get used to describe how this happens that are intuitive to us because we see and in these things in our daily observations. The first one is the “ Hydraulic - Electroanalogy” and, the other is the “Earth gravity analogy” (marble run) of electrical potential.

Its good to look at both of these analogies because they both have strengths and limitations.

A waterwheel or turbine can be like a simple circuit.

Water under pressure flows thru out the hose, to move to low pressure (no pressure state, to find equilibrium).

We can use this flow to do work turn a water wheel.

In this analogy the difference in pressure between the town water that comes from the dam and all the infrastructure upstream like water towers and pumping station AND the “zero” pressure of standing water out in the open air… represents the Voltage.

but before we do this we need to know whats going on inside a breadboard

Electric circuits take the energy, the difference in potential and apply this energy to do work. We convert one kind energy to another form. We convert the pressure or voltage and of the charged particles current to a different form of energy

• we convert the pressure of the water in the hose to turn the wheel
• we convert electric charge to heat - pass electricity thru an LED which excites semi conductor material in that releases photons (light)

Put in more charged particles(current) in, or ramp up the pressure (voltage) and we can get the thing to do more work

Of course our conductors and pipes aren't perfect - we lose a bit of energy getting it to where the work needs to be done. Think of it this way, you loose a bit of energy for every metre of pipe you run thru ( there's turblance & the friction of the water rubbing up against itself and the pipe- which turns into heat or vibrations or noise. This all eats into the energy we have for doing the work.

Remember before when we were talking about pipes I said it was all on the flat and all powered by the pressure in pipes?

The second analogy is the Earth gravity model - Think of a marble race or even a hot wheels race track.

The force of Gravity here on earth is something we are intuitively familiar with. What goes up, must come down and we can use this potential to do work.

Check out this animation

• Soldering Iron,
• Screw Driver,
• side-cutters,
• wire stripper,
• plyers,
• tweezers,
• multimeter (demonstrate continuity, resistance & voltage)
• helping hands,
• desoldering
• hot glue (explain safety measures)
• solder ( explain safety measures )
• Flux,
• tip cleaner
• heat shrink.

Types of solder joints -

• Thru hole,
• Surface mount,
• No Solder - bread boards and jumper cables, prototyping boards.

A microcontroller (or MCU for microcontroller unit) is a small computer on a single integrated circuit.

• one or more CPUs (processor cores)
• memory
• programmable input/output peripherals
• can be mixed signal devices interacting with
  • digital signals
  • analogue signals

Microcontrollers are small, low powered and robust, making them perfect for embedded systems such as:

• medical devices
• remote controls
• office machines
• appliances
• power tools
• toys
• wearable technology

Arduino is an open source computer hardware and software organisation, project, and user community ¹⁾

• The hardware is based on the Amtel 8-bit AVR MCU
• The software uses the Processing IDE, with a simplified version of the Java programming language
• Open source has led to the creation of a huge range of
  • clones
  • compatible devices
  • peripherals
• A strong community means
  • “Someone, Somewhere has solved the problem”
  • we can run this workshop using and adapting existing resources.

The best place to know where to start is to look at the library(s) that we included in our code. Usually there will be some sort of documentation along with the library. In our example sketch, we can find the included library and look for more information about it by going to Tools → Manage Libraries.

[photo of libraries panel]

To see which libraries are installed in the IDE, make sure to select the ‘Installed’ filter on the panel.

[photo showing installed]

Once we’ve found the library, click on more info.

Fast LED DemoReelAdaptedMick1DEC - got this so they can chose 1 or 2 or three patterns (rainbow, rainbowWithGlitter, confetti, sinelon, juggle, bpm) that they can choose from

strandtest_wheel - hopefully we'll manipulate this one so the can pull one or two of these too

would be good to do a basic binary (non library ) one

Sketch Name	Library Name	Function Included	Description	Output	Input	Functions, Variables, Structure	Notes	GIF
Neopixel_simple	Adafruit NeoPixel		Adds one green pixel at a time				change the colours by adding
RGBWstrandtest	Adafruit NeoPixel	colorWipe					to display just one of these patterns remove the other functions just after the Loop. Otherwise the strand test demo in the listed sequence.
		whiteOverRainbow(75, 5);
		pulseWhite(5);
		rainbowFade2White(3, 3, 1);
matrixtest	Adafruit NeoPixel						change colours and change what it writes - but i think the the 4×4 matrix is too small
MatrixGFXDemo	Adafruit NeoPixel

Physics Videos by Eugene Khutoryansky's animated visualisations of "Electric Circuit Components"

Steve Mould's video on Spintronics "Mechanical circuits: electronics without electricity"

https://www.youtube.com/watch?v=xrQCPYsoBKk

https://www.arduino.cc/reference/en/

Daniel's Base Design

2023 update of base to fit glass jar from Kmart

2023 update of acrylic xmas tree artwork

2023 update of cardboard box cut file

cardboard box lid cut file

zip of Arduino IDE Xmas LED tree sketch

Electronics 101 workshop Powerpoint from Aug