13-04-2015, 10:32 AM
need design of microcontroller based ultrasonic distance meter ppt
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ppt for microcontroller based ultrasonic distance meter
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need design of microcontroller based ultrasonic distance meter ppt
05-04-2017, 05:00 PM
There are several ways to measure non-contact distance. One way is to use 40 kHz ultrasonic waves to measure distance. Ultrasonic transducers measure the amount of time it takes a sound pulse to travel to a particular surface and return as reflected echo. As the audible range of the human ear is between 20 Hz and 20 kHz, it is insensitive to ultrasonic waves falling beyond that range, and therefore, ultrasound waves can be used for applications in industries or vehicles without hindering the human activity.
They are widely used as range meters and proximity detectors in industries and also in parking assistance systems. The distance can be measured using the pulse echo and phase measurement method. In this project, the pulse-echo method is used. The unit of measurement uses pulses on the continuous signal in the transmission frequency range of the ultrasonic transducers. The signal is transmitted by an ultrasonic transducer, reflected by an obstacle and received by another transducer in which the signal is detected. The time delay of the transmitted and received signal corresponds to the distance between the system and the obstacle.
Techniques for measuring distance by ultrasound in the air include the continuous wave and pulse echo technique. In the pulse echo method, a burst of pulses is sent through the transmission medium and reflected by an object held at a specified distance. The time required for the pulse to propagate from the transmitter to the receiver is proportional to the distance of the object.
In this project, an ultrasonic module is connected to the microcontroller, and an ultrasonic transducer comprising a transmitter and a receiver is also used. The transmitted waves are reflected backwards from the object and received by the transducer. The total time taken from the sending of the waves to the receiving end is calculated taking into consideration the speed of sound. Then the distance is calculated by a program that runs on the microcontroller and is displayed on an LCD screen connected to the microcontroller.
The power supply consists of a 230 / 12V reduction transformer, which lowers the voltage to 12V AC. This is converted to DC using a Bridge rectifier. The undulations are removed using a capacitive filter, and then regulated to + 5V using a 7805 voltage regulator, which is required for the operation of the microcontroller and other components. The scope of the project in the future can be enhanced by the use of high frequency transducers to make it suitable for medical applications such as the ultrasound machine.
BLOCKS DIAGRAM
Techniques for measuring distance by ultrasound in the air include the continuous wave and pulse echo technique. In the pulse echo method, a burst of pulses is sent through the transmission medium and reflected by an object held at a specified distance. The time required for the pulse to propagate from the transmitter to the receiver is proportional to the distance of the object.
In this project, an ultrasonic module is connected to the microcontroller, and an ultrasonic transducer comprising a transmitter and a receiver is also used. The transmitted waves are reflected backwards from the object and received by the transducer. The total time taken from the sending of the waves to the receiving end is calculated taking into consideration the speed of sound. Then the distance is calculated by a program that runs on the microcontroller and is displayed on an LCD screen connected to the microcontroller.
The power supply consists of a 230 / 12V reduction transformer, which lowers the voltage to 12V AC. This is converted to DC using a Bridge rectifier. The undulations are removed using a capacitive filter, and then regulated to + 5V using a 7805 voltage regulator, which is required for the operation of the microcontroller and other components. The scope of the project in the future can be enhanced by the use of high frequency transducers to make it suitable for medical applications such as the ultrasound machine.
BLOCKS DIAGRAM
![[Image: Distance_Measurement_by_Ultrasonic_Senso...gram_A.JPG]](http://www.efxkits.com/media/wysiwyg/Distance_Measurement_by_Ultrasonic_Sensor_Block_Diagram_A.JPG)
It can be understood in the following video:
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