[Parafoil] Added Analog Load Cell Sensor (same of rig-dev)

src/boards/Parafoil/Sensors/AnalogLoadCellSensor.h

+/* Copyright (c) 2024 Skyward Experimental Rocketry
+ * Authors: Davide Mor
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#pragma once
+
+#include <sensors/Sensor.h>
+#include <sensors/SensorData.h>
+
+#include <functional>
+
+// The class was copied from rig-dev, commit 5c9464e5
+
+namespace Parafoil
+{
+
+class AnalogLoadCellSensor : public Boardcore::Sensor<Boardcore::LoadCellData>
+{
+public:
+    AnalogLoadCellSensor(std::function<Boardcore::ADCData()> getVoltage,
+                         float p0Voltage, float p0Mass, float p1Voltage,
+                         float p1Mass)
+        : getVoltage{getVoltage}, p0Voltage{p0Voltage}, p0Mass{p0Mass},
+          p1Voltage{p1Voltage}, p1Mass{p1Mass}
+    {
+    }
+
+    bool init() override { return true; }
+
+    bool selfTest() override { return true; }
+
+private:
+    Boardcore::LoadCellData sampleImpl() override
+    {
+        auto voltage = getVoltage();
+        return {voltage.voltageTimestamp, -voltageToMass(voltage.voltage)};
+    }
+
+    float voltageToMass(float voltage)
+    {
+        // Two point calibration
+        // m = dmass/dvoltage
+        float scale  = (p1Mass - p0Mass) / (p1Voltage - p0Voltage);
+        float offset = p0Mass - scale * p0Voltage;  // Calculate offset
+        return scale * voltage + offset;
+    }
+
+    std::function<Boardcore::ADCData()> getVoltage;
+
+    float p0Voltage;
+    float p0Mass;
+    float p1Voltage;
+    float p1Mass;
+};
+
+}  // namespace Parafoil