Partslist
- A polystyrene block
- 2 LDRs
- 2 resistors
- A piezo buzzer
- An arduino
- wire
- A maplin pull-cord charger
- A brick
This partslist might be able to be trimmed down a lot, and there are various combinations of things which could be swapped in. For example, the pull-cord charger may be replaced by a regular electric motor, a capacitor and supporting nick-nacks, but the charger is probably easier to engineer for now. The polystyrene block and the brick may be able to be dropped in favour of a direct mechanical linkage.
I'm no specialist with analog electronics, but I think it should be possible to dispense with the arduino altogether. Anyone out there I can sanity check an alternative circuit with?
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