We need to come up with a way to test the depth of a bore hole. The old string method works but takes WAY too long in some instances. I am looking for ideas or help me along with a couple ideas I have
1. Sonar or reflection wave. Problem is possibly if sound wave is not carefully aimed, it might distort and null the return. I am also not sure what electronics are needed to send and receive the signal.
2. Reverberation or standing wave frequency. Sort of like the water glass deal. As the hole gets longer, the waves would get longer, thus a lower frequency. I was thinking of sending an audible (or maybe inaudible) sound wave down the hole and monitor changes is frequency. or maybe initiate a frequency sweep and determine where the resonance is which could then determine the length or depth.
Ideas?
1. Sonar or reflection wave. Problem is possibly if sound wave is not carefully aimed, it might distort and null the return. I am also not sure what electronics are needed to send and receive the signal.
2. Reverberation or standing wave frequency. Sort of like the water glass deal. As the hole gets longer, the waves would get longer, thus a lower frequency. I was thinking of sending an audible (or maybe inaudible) sound wave down the hole and monitor changes is frequency. or maybe initiate a frequency sweep and determine where the resonance is which could then determine the length or depth.
Ideas?