11-09-2012, 02:49 PM
can u please send me a ppt report of the topic microcontroller based ultrasonic distance meter..
11-09-2012, 02:49 PM
can u please send me a ppt report of the topic microcontroller based ultrasonic distance meter..
24-12-2012, 04:40 PM
Microcontroller-based Ultrasonic Distance Meter
Microcontroller-based Ultrasonic.pdf (Size: 698.2 KB / Downloads: 295) There are several ways to measure distance without contact. One way is to use ultrasonic waves at 40 kHz for distance measurement. Ultrasonic transducers measure the amount of time taken for a pulse of sound to travel to a particular surface and return as the reflected echo. This circuit calculates the distance based on the speed of sound at 25°C ambient temperature and shows it on a 7-segment display. Using it, you can measure distance up to 2.5 metres. For this particular application, the required components are AT89C2051 microcontroller, two 40kHz ultrasonic transducers (one each for transmitter higher pulse excitation voltage or a better transducer. Here the microcontroller is used to generate 40kHz sound pulses. It reads when the echo arrives; it finds the time taken in microseconds for to-and-fro travel of sound waves. Using velocity of 333 m/s, it does the calculations and and receiver), current buffer ULN2003, operational amplifier LM324, inverter CD4049, four 7-segment displays, five transistors and some discreet components. The ultrasonic transmitter receiver pair is shown in Fig. 1. Ultrasonic generators use piezoelectric materials such as zinc or lead zirconium tartrates or quartz crystal. The material thickness decides the resonant frequency when mounted and excited by electrodes attached on either side of it. The medical scanners used for abdomen or heart ultrasound are designed at 2.5 MHz. In this circuit, a 40kHz transducer is used for measurement in the air medium. The velocity of sound in the air is around 330 m/s at 0°C and varies with temperature. In this project, you excite the ultrasonic transmitter unit with a 40kHz pulse burst and expect an echo from the object whose distance you want to measure. Fig. 2 shows the transmitted burst, which lasts for a period of approximately 0.5 ms. It travels to the object in the air and the echo signal is picked up by another ultrasonic transducer unit (receiver), also a 40 kHz pre-tuned unit. The received signal, which is very weak, is amplified several times in the receiver circuit and appears somewhat as shown in Fig. 2 when seen on a CRO. Weak echoes also occur due to the signals being directly received through the side lobes. These are ignored as the real echo received alone would give the correct distance. That is why we should have a level control.
22-07-2013, 08:42 PM
i have no prjct report,can u send the ppt without the report
26-07-2013, 11:36 AM
To get full information or details of microcontroller based ultrasonic distance meter please have a look on the pages
http://seminarprojectsshowthread.php?mode=linear&tid=72472 https://seminarproject.net/Thread-ultras...pid=164192 https://seminarproject.net/Thread-microc...pid=164193 if you again feel trouble on microcontroller based ultrasonic distance meter please reply in that page and ask specific fields in microcontroller based ultrasonic distance meter |
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