How can i measure distance using ultrasonic (only analog)

[liakofan]

My problem is that i have to measure distance using an ultrasonic receiver ,in order to measure the water level of a small tank ,but i have to use only analog means,no microcontrollers , can anyone help me??
i thought about using a counter that would start counting when the transmiter send a pulse and stoped when the receiver is activated and then transform time into distance somehow.Am i even close?
PLZ help if you can
THNX!

 

[techieno1]

Re: How can i measure distance using ultrasonic (only analog

Yes, your concept is right. You have to transmit a sound wave using sound transmitters and receive the reflected sound signal using a hydrophone array. Measure the strength of the received signal, compare with the transmitted signal and estimate the possible depth of the tank/river. This principle is used in passive sonars for finding the under water targets, fish population and depth.

But couldn't understand your implementation requirement. Counter is a digital circuit. I think you have to use algorithm to estimate the depth of the tank based on the received analog signal strength. Read about SONAR systems, you will get some idea.

hope this helps,

Regards..

My problem is that i have to measure distance using an ultrasonic receiver ,in order to measure the water level of a small tank ,but i have to use only analog means,no microcontrollers , can anyone help me??
i thought about using a counter that would start counting when the transmiter send a pulse and stoped when the receiver is activated and then transform time into distance somehow.Am i even close?
PLZ help if you can
THNX!

 

[liakofan]

Re: How can i measure distance using ultrasonic (only analog

Thnx for the help but the problem is that the pulse received is quite unstable and i cant figure out how to measure it

maybe it would help if i gave you the project i am making:

https://www.electronics-lab.com/projects/sensors/007/index.html

 

[Audioguru]

The project you are making has a bad translation of its title.
It is not an ultrasonic radar circuit, instead it is a very old motion detector kit. It detects a change in the level of the reflected ultrasonic signal.
Its schematic and its parts list have errors.

 

[Canadian_Jim]

Problem solved. O/P to a 4-20mA lcd and you're done.

 

[FvM]

Re: How can i measure distance using ultrasonic (only analog

The above discussion about "it's not a radar" is quite funny.

I suggest to look at one of liakofans cross postings on this topic

The said "radar" circuit has been mentioned there by another contributor.
I gave a comment (similar to Audioguru), that it's a poor designed intrusion detector, not suited for the discussed problem.

Seven hours later, liakofan claimed it as "the project i am making". He may possibly have found the circuit before, but why not watching his own thread?

That's why I really hate this bad cross posting habbit.

Just to remember edaboard rules:

3.0 UNWANTED TOPICS/POST
Off-topic, hammering, spamming and cross posts are strongly unwanted. They're an unuseful load of EDAboard forum areas.

 

[davidgrm]

You do not need sonar. You set the ultrasonic above the water in the tank and then simply measure the distance to the water. Of course this would be much easier to do with a MCU

 

[Audioguru]

There is cross-posting here and there is more cross-posting all over the web about this simple circuit requirement.

 

[liakofan]

Re: How can i measure distance using ultrasonic (only analog

i'm really sorry about the cross posting but the other thread was pretty old and i wasn't sure i would get an answer that is why i posted my own afterward.my teacher gave me this cirquit and i hav to make do with that,otherwise you can just buy something like the one mentioned above.If anyone can help me with this particular cirquit and how am i going to measure distance i would be obliged

 

[FvM]

As clearly said, the so-called "radar circuit" has a misleading title and isn't suited for any kind of distance measurement.

The second circuit posted by vfone in your other thread can be used as a starting point. It has the basic features of a echolot distance measurement, particularly suited for small bandwidth air US transducers:
- periodically sending a short burst
- amplifying the received signal and evaluating the envelope
- determining the flight time, in this case even by an analog circuit
Additional issues have to be managed when using a single transducer for send and receive

 

[Audioguru]

Your teacher gave you the defective circuit from Electronics-Lab? It is an old kit that was originally printed in Greek. A robot poorly translated it into English. It has errors and does not use radar nor sonar and does not measure distance.

At Electronics-Lab there is another project called "Park-Aid" that is from Red Circuits. It measures distance and lights LEDs to show the distance. It uses IR but can be easily modified to use ultrasonics.
It sends an IR beam from a car to a reflecting surface in a garage and its LEDs indicate the signal strength of the reflection caused by distance.