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I have this project, an RC Boat which can be operated in shallow water

is there a way i can measure the depth of water below the RC boat? what sensor should I use?
the boat will be deployed in a maximum depth of 1m.

The boat should read the depth at least a foot below it up to a meter..
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I have this project, an RC Boat which can be operated in shallow water

is there a way i can measure the depth of water below the RC boat? what sensor should I use?
the boat will be deployed in a maximum depth of 1m.

The boat should read the depth at least a foot below it up to a meter..

Well real boats use ultrasonic sender/receivers to measure water depth and fish contacts. However finding hobby type ultrasonic sensors rated for in water service may be a problem.

Lefty
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There are a few online stores that sell underwater ultrasonic transducers, e.g. in the UK Maplin and Rapid sell this one http://www.rapidonline.com/Electronic-Components/Underwater-ultrasonic-transducer-200KHz-plastic-case-35-1810/?source=googleps&utm_source=googleps.
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There are a few online stores that sell underwater ultrasonic transducers, e.g. in the UK Maplin and Rapid sell this one http://www.rapidonline.com/Electronic-Components/Underwater-ultrasonic-transducer-200KHz-plastic-case-35-1810/?source=googleps&utm_source=googleps.

hi, this seems to be an expensive sensor by itself (without the module) is there a cheaper alternative for this?.. and If Suppose I will buy this, can I replace the sensor of an ultrasonic sensor module with this???
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No, these transducers work at 200KHz, whereas the ones in ultrasonic modules for use in air are more commonly 40KHz.
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No, these transducers work at 200KHz, whereas the ones in ultrasonic modules for use in air are more commonly 40KHz.

can you suggest a cheaper way, those fishfinder have a blind spot of 2 ft and lower... my goal is to measure depth at least from 20cm up to 4ft...
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The only cheaper way I can think of is to make your own ultrasonic transducers from raw piezo elements (these are available - or at least used to be - because a long time ago I used them for tuning the frequency of lasers). You would need to machine a tapered metal block to mount them on, in order to match their stiffness to the compressibility of water. And you would need to waterproof them.

Or, with help from Google, you may be able yo find some less expensive transducers designed for use underwater. Remember, it's not just that you need waterproof transducers, you also need a reasonable acoustic impedance match between the transducer and the water it is immersed in.
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The only cheaper way I can think of is to make your own ultrasonic transducers from raw piezo elements (these are available - or at least used to be - because a long time ago I used them for tuning the frequency of lasers). You would need to machine a tapered metal block to mount them on, in order to match their stiffness to the compressibility of water. And you would need to waterproof them.

Or, with help from Google, you may be able yo find some less expensive transducers designed for use underwater. Remember, it's not just that you need waterproof transducers, you also need a reasonable acoustic impedance match between the transducer and the water it is immersed in.

hmm, It seems to be more complicated than before smiley-lol, If I happen to see or purchase a underwater Transducer 200khz, how would I drive it, how can I produce a module(Circuit) like the one in an ultrasonic transducer?
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is the water clear or muddy?
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is the water clear or muddy?

clear smiley
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