As just stated, in this project we need two different kind of sensors: one to detect when the washing machine starts/stop, and one to detect when someone enters/exits the laundry room. The former task can be achieved by using a sound detector, that is, a device that is able to measure the environment sound level; while the latter task can be achieved by using a light sensor, that is, a device that is able to measure the environment light. Both these signals can be compared with thresholds in order to detect our relevant events.
When the washing machine is running, we should measure a high sound level for a long amount of time; while it is not running, the environment sound should be near to zero for a long time. On the other hand, we can assume that the person designed to pick up the washed clothes has to turn the light on in the laundry room, while the light is normally turned off when there is nobody in the room.
