IIRC I breadboarded it as a curiosity and saw that it would work, but have never actually used it. He has published several similar designs http://electronicdesign.com/Authors/Index.cfm?AD=1&AuthorID=934&DisplayTab=Authors, most recently one in 2001 that has dc output and may be more suitable.LizzyB: I have seen the EDN circuit offered as a solution in the past, but I have never seen anyone tell of a successful (or otherwise) use of the circuit. Have you used it or know of someone who has (excepting the author)?
Marmitas, yes please, can you send me the schematic of your board ?....
http://www.freescale.com/files/sensors/doc/data_sheet/MPX2010.pdf?fsrch=1
I am working on a project to meassure airspeed on an RC airplane and can send you the schematic of the amplifier circuit
Just to add to the flap idea, maybe a light interrupter mounted to the flap shaft so to block light to an LDR when no air flow and give full light at the maximum, would also be possible to fit a aquadratic encoder disc to the shaft to monitor the flap position. Both options don't add any resistance to the flap movement.Why not a flap in the air stream attached to the spindle of a suitable potentiometer, you can read the value of the pot with readadc.
The greater the air flow the higher the flap will rise. Make it very light e.g. polystyrene to be sensitive.
Marmitas,PD0 connects to a Picaxe analog input pin
Hello,TSWEENEY,
Yes I tested it as follows:
I wrote code to read the voltage outpu ton Pin AD0 and display the information on an LCD.
Then I attached a rod that ended 4 feet forward of the front of my car (not legal in NY)to get clean air. I taped a 1/4" ID flexible tube to the rod with the one end facing forward and the other end attached to the dynamic pressure inlet of the sensor. A friend drove the car from 40 to 75 miles an hour in increments of 5 miles an hour. I recorded the readings I was getting on the LCD on a piece of paper. We repeated the reading in the oposite direction on the same highway. Then using Xcell I ploted the data and created the calibration equation (it is a parabola). I have not tested it in an airplane but that is next. I hope this helps, if you need more detailed info, send me a PM
Andrés RodrÃguez
I think I said that as well ! great minds think alike.5 m/s (I'm assuming meters/sec, not miles/sec ;-) is about 5MPH/8KPH, which probably won't be enough for a pitot tube.
Look for a solar motor kit with fan blades that will fit (or can be adapted to fit) in the duct. Use it as a generator with the air flow in the duct turning the fan. Put a low value resistor (100R - 330R) across the output of the motor to provide a load and use ADC to measure the voltage produced.
John