More than smoke- How To

Posted on March 9, 2012 by


List of Components: List of Materials:
1 Arduino Board A cardboard box
1 Bread Board Cardboard lengths
16 Wires
(to be soldered) Newspaper
6 LEDs Clear sticky tape
6 Light Resistors Cling film
1 10K Resistor (For sensor) Masking tape
1 Carbon Monoxide Sensor Scissors
1 Soldering iron Cutting knife and mat
1 Reel of solder wire Black paint or spray paint

To make the transparent lungs you will need to make a model of a lung using cardboard and newspaper as shown in the picture below. Wrap the model in two layers of cling film, ready to be taped. For our lungs we used five layers of tape and additionally went over the edges to ensure that we hadn’t left any gaps. Depending on the size of your lung model and your box you may have to adjust the amount of tape you use accordingly.

Next, you will need to cut a line down one edge of the lungs with a knife or scalpel to remove the model. Repeat for the other lung.

The same process is required to make the tubes for the smoke to go into. Once they have been made, attach the tubes to the lungs with more tape and seal up the edges.

To prepare the box, for installation and for maximum effect, paint the whole of it black. This will make the lungs stand out and become the focus of attention. You will also need to make a tray to go at the bottom of the box to conceal the Arduino and bread board. The next step is to cut out a hole for the tube to go through in the centre of the top of the box. You will also need to make holes at the back of the box if you are powering your Arduino board via a laptop computer.

Before you set up the circuit we must first prepare the components. This requires a fair amount of soldering. To solder the LEDs you will require twelve wires that are long enough to reach the bottom of your lungs that will be hung in the centre of the box. We suggest you measure the distance and be a bit generous with the length to make room for any errors or difficulties that may occur when soldering. You will also require six resistors for the LEDs. Attach a resistor to the ground (-) leg of all the LEDs and solder. Then solder a wire to each leg as shown below. (If the wire you are using is too thick you will need to solder a smaller piece of wire to the end of it to fit into the breadboard).

The next action to take is to solder four wires to the carbon monoxide sensor. You will also need to solder the 10k resistor to the ground wire that is next to the wire that goes to 5v. Once this has been done we can now connect the circuit.

The Arduino code: LungCOSensor

Set up the circuit as shown in the diagram and uploaded the code to your Arduino board. The circuit works by attaching wires to individual digital pins for each LED. Each set of coloured LEDs light up for a set range of values, from lowest (blue) to highest (red) intensities of carbon monoxide that is being detected by the sensor.

Once the tested and working circuit has been completed, you can then pierce holes into the lungs to insert the carbon monoxide sensor and the LEDs. Three consecutive holes will need to be made in each lung for a blue, white and red LED. This will show a progression in the amount of carbon monoxide present. When you are satisfied with the positioning of the holes, insert the LEDs and carbon monoxide sensor and go round the edges with clear sticky tape to ensure that no smoke will escape the lung.

The lungs and circuit are now ready to be inserted into the box. Hide the Arduino and bread boards under the box tray and tuck in the wires at the back neatly. Thread the tube through the hole at the top of the box and secure the hanging lungs with wire. We have used black electrical wires to hold up our lungs but you may choose to use fishing wire or cotton thread.

The preparation and making has finished, you are now ready to start your experiment!

By Daniel Frangiamore, Django Powell and Sophie Dear

Posted in: how-to's