35 lines
994 B
C#
35 lines
994 B
C#
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using System;
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using Microsoft.SPOT;
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using Microsoft.SPOT.Hardware;
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using GHIElectronics.NETMF.Hardware;
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using GHIElectronics.NETMF.System;
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namespace PlaneOnBoardSoftware
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{
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class PitotTubeSpeedSensor
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{
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AnalogIn aiPort;
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const float RLuft = 287.058f;
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public float BarometricPressure = 100000; //Pa;
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public float DynamicPressure; //Pa
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public float Temperature = 20;
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public PitotTubeSpeedSensor(AnalogIn AnalogInPort)
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{
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aiPort = AnalogInPort;
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aiPort.SetLinearScale(0, 3300); //mV
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}
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public float GetSpeed()
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{
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float roh = BarometricPressure / (RLuft * (Temperature + 273.15f));
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DynamicPressure = (aiPort.Read() / 5000f - 0.04f) / 0.00009f; //in Pa
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if (roh > 0 && DynamicPressure > 0)
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return (float)MathEx.Sqrt(2 / roh * DynamicPressure);
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else
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return 0;
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}
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}
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}
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