BlockLowPass2.hpp

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/**
 * @file blocks.h
 *
 * Controller library code
 */

#pragma once

#include <px4_platform_common/defines.h>
#include <assert.h>
#include <time.h>
#include <stdlib.h>
#include <math.h>
#include <mathlib/math/test/test.hpp>
#include <mathlib/math/filter/LowPassFilter2p.hpp>

#include "block/Block.hpp"
#include "block/BlockParam.hpp"

#include "matrix/math.hpp"

namespace control
{

/**
 * A 2nd order low pass filter block which uses the default px4 2nd order low pass filter
 */
class __EXPORT BlockLowPass2 : public Block
{
public:
// methods
    BlockLowPass2(SuperBlock *parent, const char *name, float sample_freq) :
        Block(parent, name),
        _state(0.0 / 0.0 /* initialize to invalid val, force into is_finite() check on first call */),
        _fCut(this, ""), // only one parameter, no need to name
        _fs(sample_freq),
        _lp(_fs, _fCut.get())
    {}
    virtual ~BlockLowPass2() = default;
    float update(float input);
// accessors
    float getState() { return _state; }
    float getFCutParam() { return _fCut.get(); }
    void setState(float state) { _state = _lp.reset(state); }
protected:
// attributes
    float _state;
    control::BlockParamFloat _fCut;
    float _fs;
    math::LowPassFilter2p _lp;
};

} // namespace control