- A strong plastic cup
- Four felt-tipped pens Gaffer tape (strong and very sticky)
- A small DC motor 1.5v - 4.5v
- A couple of AA batteries
- Battery holder
- Electrical wire and crocodile clips
- An off centre mass - a blob of plasticine/ BlueTac or a slice of cork cut diagonally (works better than the plasticine)
Learning Objectives- Technology Technical Knowledge
Understand and use electrical systems in their products [for example, series circuits incorporating switches, bulbs, buzzers and motors]
Before you start building the body of the ArtBot practice wiring up the motor circuit and check that the batteries power the motor. (There's no need to worry about getting the negative and positive sides of the battery round the right way. Motors are bi-polar - reverse the poles and the motors spins in the other direction)
1) With the plastic cup upside down position and attach the four pens around the cup with the cap ends facing up. Make sure that nib of the of each pen is stands proud of the cups rim. Check that you can remove the caps easily. Replace the caps.
2) Turn the ArtBot the right way up and make sure that it stands on its legs.
3) Gaffer tape the motor to the top of the ArtBot (the base of the cup). Position it so that the shaft of the motor over hangs the edge of the cup.
4) Gaffer tape the battery to the side of the cup.
5) Connect the battery to the motor using the wires and crocodile clips (Careful with the last connection because of you have wired it correctly the motor will start and the ArtBot will be off!)
6) Un-clip one of the motor connectors to turn the motor off
7) Push the off centre mass onto the shaft of the motor. (Plasticine - experiment with the size of the plasticine. The larger the plasticine the more effort it will take for the motor to turn. Too much plasticine and the motor wont be able to turn the shaft, too little and the speed of the shaft turning will tend to cause the plasticine to spin off. Make sure that the plasticine doesn't stick or get caught on the side of the plastic cup or the motor casing.)
8) Re-attach the wire from the motor to the battery (that you unclipped in 6 above). The motor should now spin.
9) Place the ArtBot on a flat surface - it should wobble and jiggle around. If it doesn't check the wiring and make sure that the plasticine isn't stopping the motor shaft from spinning
10) Once you are happy that the ArtBot works remove the caps from the pens, place the ArtBot on a piece of plain paper and watch it create spiral patterns.