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Secret Knock Door Unlocker

Secret Knock Door Unlocker

Parts List/Cost

                273-258 Servo Motor from RadioShack: $3.49

                IRF510 Mosfet Transistor from Radioshack: $1.99

                5940534 Microphone from Fry’s Electronics: $3.99

                External DC Power Supply

                Cardboard Box

                Duct Tape

                String/Thread

                Total Cost: $9.47

Setup

                HW

  1. Connect the electrical components as follows:

Untitled.jpg

The leads on the motor are interchangeable. The power supply outputs at least the minimum current required by the servo motor. In our case, we had a 9VDC/1A power supply for a 3VDC/700mA motor.

Mount the servo using a cardboard box corner section such that the axle of the servo is at the same height as the top of the deadbolt (for maximum force on the deadbolt). Attach the axle to the deadbolt by a thread so that the thread coils when the motor turns.

Connect the microphone to the Audio In channel and mount it such the knocks will be audible. Plug in the power supply.

               SW

  1. Open Door Knocker.vi
  2. Select the physical Audio In and Analog Out channels on the front panel.
  3. Run the VI. The default knock ratios correspond to 4 equally spaced knocks. To record a custom one, press the Record button and record your new knock.
  4. The leniency control on the front panel can be used to vary how lenient the program is on the knock pattern matches. The sensitivity control can be used to adjust the microphone.

Explanation

The VI runs and detects the knocks on the door by the peaks obtained from the Audio Input task. From those peaks, it will compute relative ratios between the knocks and compare them to predefined values. If there is a match, we send a voltage to an Analog Output channel. This voltage will pass to the mosfet transistor and complete the circuit required for the motor to operate. This results in a motor spinning for half a second and unlocking the door.

ATTACHED: VI CODE

Comments
labviewjunior
Member
Member
on

Hello. I'm introduction to labview. So I tried to use your example to pormote my labview skills. But I think you may have missed some vi, you said open Door Knocker.vi but there isn't any vi named it. If you mind check it for once? It will be great if I can got your answer. Thank you.

jonnwarne
Member
Member
on

Thanks for letting us know these information are really awesome and helpful who are seeking these information. These type of  smart lock have proper control and command system, you can easily control via different devices. For more details have a look where can get more information about smart lock.

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