sound activated motor

Fascinating Flowervase: Sound Activated Motor Driver

fantastic flowervase If you are looking for an idea to build your own simple electronic gift, your search may end here! Described is a minimalist design for you, realized using a handful of discrete components. The major component in this design (Sound Activated Motor Driver) is an inexpensive, and widely available robotic motor, which is nothing but a 5VDC operated mini motor with a reliable plastic gear mechanism. Don’t forget to buy a 60mm (or near) diameter robotic wheel with the robotic motor. This combination (geared motor + wheel) will simply the mechanical work behind this little project.

  • Step 1: Assemble the whole circuit on a piece of general purpose circuit board asindicated in the schematic circuit diagram
  • Step 2: After construction and testing, enclose the finished circuit in a small box, including the battery holder. Drill a suitable (3mm-5mm) hole in front of the box to leave an open window for the electret microphone
  • Step 3: Stiffly mount the motor inside the box so that its rotating shaft slightly protrudes through the top of the box. Now attach the wheel to the motor shaft and stick any lightweight flowervase on the top of the wheel firmly using a suitable glue
  • Done! The flowervase starts rotating slowly (for a finite duration) when there is a loud clap or whistle.

Schematic of the Sound Activated Motor Circuit

sound activated motor

Parts List

  • IC1: LM555
  • T1: BC547B
  • D1,D2: 1N4007
  • LED1: 5mm Red
  • R1: 10K ¼ w
  • R2: 1M ¼ w
  • R3: 150K ¼ w
  • R4: 1K ¼ w
  • R5: 100K ¼ w
  • R6: 220Ω ¼ w
  • C1,C2,C4: 100nF/50V Ceramic
  • C3: 47µF/16V Electrolytic
  • C5: 100µF/16V Electrolytic
  • M1: 5V ROBO MOTOR (see text)
  • C.MIC: Electret Condensor Microphone

Lab Note (Tested on 08 February 2014)

  • Prototype tested with a 5VDC/75 RPM plastic-gear motor
  • Supply Voltage: 6VDC (1.5VAA x 4)
  • Motor Run Time: Near 5 Seconds with C3 = 47uF
  • Red LED (LED1) is optional. However, it can be used to add a pleasing visual effect to the flowervase


Join the conversation!

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  • sudha

    dear sir, can you please briefly explain working of this circuit

  • krokkenoster

    This is a circuit with a googal (10^99) uses! It can even be used as an alarm all you do is to drive a suitable steel peg into the ground and fit a CRYSTAL mike or headphone to it and use that as the input Dogs running about are not really a problem as they are too light to make enough “earthquakes” {Except if you have Kachatka awcharec or similar horse type size of dog] but I doubt if there would be anyone with such a doggy in the suburbs If a person would walk the steps get detected and a light or banshee activated