Regarding the single transducer ultrasonic sensor, I finally had a chance to test the one i purchased from Banggood.
The good news: it works (no surprise there). I set up a simple test rig with an Arduino Mega and using sample code, it immediately started reporting fairly accurate distances from the sensor.
The bad news: Range is limited, both long and short. Short range was no closer than 20cm. Long range was difficult to really measure, but it appears to be around 4 meters.
I think olewsaa's suggestion that two devices be used is a good one. From what I read the single sensor needs a certain amount of time to settle before the receive signal is reliable, hence the close range limit. In my case, no good for tank level monitoring.
I think in my case I'm going to go back to my contact sensor design for my forward tank. It doesn't give me much resolution, but all I really need to know is approximately what the tank level is.
As far as using the ultrasonic sensor as a parking sensor, I suppose you could do it, but not to 40'. I would guess for longer distances you would need considerably more power to send out the pulse, and more sensitivity to receive it. Then there's the problem of spreading of the beam and actually detecting what you want. I also think it would be cool to know how close I am to my pontoon, but there are other priorities right now!
The good news: it works (no surprise there). I set up a simple test rig with an Arduino Mega and using sample code, it immediately started reporting fairly accurate distances from the sensor.
The bad news: Range is limited, both long and short. Short range was no closer than 20cm. Long range was difficult to really measure, but it appears to be around 4 meters.
I think olewsaa's suggestion that two devices be used is a good one. From what I read the single sensor needs a certain amount of time to settle before the receive signal is reliable, hence the close range limit. In my case, no good for tank level monitoring.
I think in my case I'm going to go back to my contact sensor design for my forward tank. It doesn't give me much resolution, but all I really need to know is approximately what the tank level is.
As far as using the ultrasonic sensor as a parking sensor, I suppose you could do it, but not to 40'. I would guess for longer distances you would need considerably more power to send out the pulse, and more sensitivity to receive it. Then there's the problem of spreading of the beam and actually detecting what you want. I also think it would be cool to know how close I am to my pontoon, but there are other priorities right now!