Washing machine alarm

Most electric home appliances have some sort of alarm when human attentions is required. For instance Microwave oven beeps three times when cooking is done. But is seems that Victor‘s new washing machine lacks this functionality. After forgetting to take clothes few times he started thinking of new hack.

So he came up with accelerometer based alarm system that monitors washing machine activity and sounds when washing is done. He wanted device be simple, attachable and stand alone so it wouldn’t void any warranties and would work with any type of machine. Using accelerometer was obvious choice, because washing machines vibrate when operate. Monitor is based on PIC12F683 microcontroller and MMA7361 3-axis accelerometer. Alarm is sounded using piezo buzzer. Device monitors accelerometer and if there is no shake within minute it stars alarm. I think this is not only good for detecting end of wash but also good for detecting failures of any devices that does shake a bit.