Introduction to Ultrasonic Distance Meter

(2) The type of sound wave used for this experiment was longitudinal waves in which the vibration occurs along the direction of propagation

After the positions were recorded for frequencies 1,803 Hz, 2,402 Hz, 3,002 Hz, 3,600 Hz, and 4,201 Hz, the wavelength was determined for each. This was done by subtracting the initial position from the final position (position final–position initial=wavelength). Using the calculated wavelength, the speed of sound in air at each frequency was determined by multiplying the wavelength by the frequency (speed of sound=wavelength x frequency). By adding the five speed values and dividing by the number of speeds, the average speed of sound was calculated. Then 344 m/s was used as the accepted

Ultrasonic sensors emit short, high-frequency sound pulses at regular intervals. These propagate in the air at the velocity of sound. If they strike an object, then they are reflected back as echo signals to the sensor, which itself computes the distance to the target based on the time-span between emitting the signal and receiving the echo.

By manipulating the key characteristics of the Schmitt trigger, it produces different frequencies fed to the speaker to operate. One key component of the Schmitt trigger is to determine the high and low thresholds at 3V. This is done with the help of the data sheet values as presented in the appendix below. The next section 3.2 contains a detailed explanation of the design process.

1). Design the circuit for the given specifications. 2). Write the program code. 3).

As newer research began during the 1900s, the sonar started to make changes and new developments. Active sonar, provides pulses of sounds and listening for echoes. Gives warning if an object is in the path and returns an “echo” to the sonar transducer. The transducer can determine the range and orientation of the object. Passive sonar systems are used primarily to detect noise from marine objects (such as submarines or ships). Unlike active sonar, passive sonar does not emit its own signal, which is an advantage for military vessels that do not want to be found or for scientific missions that concentrate on quietly “listening” to the ocean. The purpose for both sonar’s is to detect the acoustic signals emanating from external

on pin 1,4,8,5 of LP2951), also as an input capacitor in the signal processing circuit(see

Sonar is simply making use of an echo. When an animal or machine makes a noise, it sends sound waves into the environment around it. Those waves bounce off nearby objects, and some of them reflect back to the object that made the noise.

Pregnancy is a very exciting time. The photos, the food, and the announcements are enough to make anyone squeal with joy. One of the most exciting times during your pregnancy is learning the gender of your baby. An ultrasound during your second trimester can reveal whether you are having a boy or girl, which will allow you to continue shopping and planning. If you are going in to have an ultrasound soon to determine the gender of your baby, use these four tips to help the ultrasound technician get a good view of your baby:

Gill, R., 2012. The physics and technology of diagnostic ultrasound: a practitioner's guide. Abbotsford, N.S.W.: High Frequency Publishing.

Multibeam echo sounders do this by sending out sound waves that widen in width as you go down away from the ship. Then, the scientists calculate the amount of times it takes for the sound waves to get back to the sounder. This determines the water’s depth. Multibeam systems (unlike other sonars) use sound wave systems to take the information involving direction from the incoming sound waves, creating lots of information from one single return. This can be used in case there is an oceanic physical structure under ground, and if a boat or submarine is coming.

LDR (Photoresistor): LDR plays a vital role here, as the whole circuit is designed around the resistance of LDR. The LDR resistance is dependant on the light intensity, when the laser is pointed at LDR it has low resistance but as soon as the signal is broken and there is no light being pointed at LDR its resistance goes high making the buzzer go OFF.

Ultrasound or ultrasonography is a medical imaging technique that uses high frequency sound waves. It is a high pitch frequency that cannot be heard by the human ear. In ultra sound the following happens: High frequency sound pulses (1-5megahertz) are transmitted from the ultrasound machine into your body using a probe. The sound wave will travel into your body until it hits an object such as soft tissue and bone. When the sound wave hits these objects some of the wave will be reflected back to the probe. While some waves may carry on further till they hit another object and then reflected back. The probe picks up these reflected sound waves and relays them to the machine. The distance and time from the probe,

Ultrasonic cleaning is a very interesting topic and occurs as a result of sound waves implemented into a cleaning liquid or solution by means of frequency transducers there are two types of transducers which are typically mounted to the cleaning tank.

The output of IC-2 is also used for lighting LED-1 indicating presence of signal. When no signal is available output of sensor module goes high and transistor LED is switched ‘OFF’. When another signal arrives, LED is switched ‘ON’ and through clock pulse at Pin No. 14 of IC-3. This makes the LED to switch ‘ON’ the appliance at first pulse and ‘OFF’ the appliance at its Second pulse arrived at its sensor. Transmitter circuits works satisfactorily with 6-9V DC. Battery but receiver circuits needs 6V regulated supply. The CAMD CM8870/70C provides full DTMF receiver capability by integrating both the band-split filter and digital decoder functions into a single 18-pin DIP, SOIC,or 20-pin PLCC package. The CM8870/70C is manufactured using state-of-the-art CMOS process technology for low power consumption (35mW, MAX) and precise data handling. The filter section uses a switched capacitor technique for both high and low group filters and dial tone rejection. The