ManualControl: fix RC override

src/modules/manual_control/MovingDiff.hpp

@@ -0,0 +1,69 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2021 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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+ *
+ ****************************************************************************/
+
+#pragma once
+
+#include <lib/mathlib/math/filter/AlphaFilter.hpp>
+
+class MovingDiff
+{
+public:
+	float update(float value, float dt_s)
+	{
+		if (!PX4_ISFINITE(value) || (dt_s < FLT_EPSILON)) {
+			// Ignore NAN
+			return NAN;
+		}
+
+		_difference_filter.setParameters(dt_s, .1f);
+
+		// Leave _diff at 0.0f if we don't have a _last_value yet.
+		if (PX4_ISFINITE(_last_value)) {
+			const float new_diff = (value - _last_value) / dt_s;
+			_difference_filter.update(new_diff);
+		}
+
+		_last_value = value;
+		return _difference_filter.getState();
+	}
+
+	void reset()
+	{
+		_difference_filter.reset(0.f);
+		_last_value = NAN;
+	}
+
+private:
+	AlphaFilter<float> _difference_filter;
+	float _last_value{NAN};
+};