how to sense the distance

[Tafari]

how to sense distance

How can I make use of microcontroller to check to distance between the two objects?

I want to use a transmitter and a receiver to monitor the distance between two objects. If there distance is too large, such as 10 meters away, my microcontroller to alarm me.

How can I achieve this? I am thinking about calculate the time delay, but not sure is it feasible or not.

By the way, which kind of receiver and transmitter shall I choose?

Thanks in advance =)

 

[blueroomelectronics]

Sonar or a Sharp Rangefinder.

 

[Tafari]

Sonar or a Sharp Rangefinder.

Thanks for reply

But i am not interested in sensing obstacles in front. What I am interested in is whether my specific object goes out of the detection range. Therefore, I guess I need a transmitter to transmit a signal and a receiver to response.

How shall I choose the transmitter and receiver?

Is there any better way to achieve this function?

Thx

 

[stanislavb]

Hi,
Sharp produce family of such sensors. I presume it can useful for you.

 

[Tafari]

Hi,
Sharp produce family of such sensors. I presume it can useful for you.

It is a distance measuring sensor which cannot differentiate my object and all other obstacles.

Thank you very much. I will try to find some helpful info from Sharp. =)