⌛ Control a relay connected device for a period of 1 to 100 seconds using a 555

The Timer555Monostable library turns a 555 Timer IC connected in Monostable mode (see 555 Timer datasheet) into a Capacitance and/or Resistance meter. The library helps in the design of capacitive sensors which can detect touch or proximity by measuring a variation in an object or sensor Capacitance.

Arduino analog read and light active switch

Vibration trigger circuit, to turn on a device for 30 seconds, resettable so that it remains on if vibration continues.