Design a smart insect repeller using ultrasonic sensor
Design a smart insect repeller circuit using ultrasonic sensor is a project that using an ultrasonic sensor as it’s based on generate frequency which can repel insects in small places. It is design to be a low cost ultrasonic insect repeller. Human beings can’t hear these high-frequency sounds. Unfo...
Main Author: | |
---|---|
Format: | Undergraduates Project Papers |
Language: | English |
Published: |
2012
|
Subjects: | |
Online Access: | http://umpir.ump.edu.my/id/eprint/4646/ http://umpir.ump.edu.my/id/eprint/4646/ http://umpir.ump.edu.my/id/eprint/4646/1/cd6716_111.pdf |
Summary: | Design a smart insect repeller circuit using ultrasonic sensor is a project that using an ultrasonic sensor as it’s based on generate frequency which can repel insects in small places. It is design to be a low cost ultrasonic insect repeller. Human beings can’t hear these high-frequency sounds. Unfortunately, all insects do not react at the same ultrasonic frequency. While some insects get repelled at 35 kHz, some others get repelled at 38 to 40 kHz. Thus to increase the effectiveness, frequency of ultrasonic oscillator has to be continuously varied between certain limits. By using this circuit design, frequency of emission of ultrasonic sound is continuously varied step-by-step automatically. For each clock pulse output from op-amp IC1 CA3130 (which is wired here as a low-frequency square wave oscillator), the logic 1 output of IC2 CD4017 (which is a well-known decade counter) shifts from Q0 to Q4. Five presets VR2 through VR6 (one each connected at Q0 to Q4 output pins) are set for different values and connected to pin 7 of IC3 (NE555) electronically. VR1 is used to change clock pulse rate. IC3 is wired as an astable multivibrator operating at a frequency of nearly 80 kHz. Its output is not symmetrical. IC4 is CD4013, a D-type flip-flop which delivers symmetrical 40kHz signals at its Q and Q outputs which are amplified in push-pull mode by transistors T1, T2, T3 and T4 to drive a low-cost, high-frequency piezo tweeter. |
---|