using ultra sonic sensor - programming, measuring the time

[anuphr]

using ultra sonic sensor

hi i am planning to use a ultra sonic sensor to measure the distance . but i do not know how to program it and use it..
measuring the time is where i am concerned...
i am using ultrasonic transmitter and receiver which are separate

 

[vigneshwara_s]

Re: using ultra sonic sensor

Hi ,

That is not a bigger task . Its very Simple. Start the timer in your microcontroller immediately after Sending signal from your ultrasonic transmitter. Notedown the Timer Count immediately after recieving the signal from your ultrasonic reciever.

The Timer Count is directly proportional to the distance.

Regards,
S.Vigneshwaran

 

[nandhu015]

Re: using ultra sonic sensor

vignesh wrote

The Timer Count is directly proportional to the distance.

One small correction, The time taken is twice the distance, as it is reflected and reaches the receiver.

Nandhu

 

[anuphr]

Re: using ultra sonic sensor

but i will be continously sending the signals how to check it now

 

[FvM]

using ultra sonic sensor

but i will be continously sending the signals how to check it now

It doesn't work.

If you won't talk of "measurement" but detection of objects, an amplitude measurement in continuous operation can give some information, but it's not very realiable, because you get standing waves in a room and possibly strong signals from large distant objects.

Pulsed time-of-flight measurement is the only simple way to get reliable distance information. In principle, frequency modulation (FMCW) radar methods could be applied as well, but they involve rather complex signal processing. You shouldn't even think of it when simple time measurement is an issue.