Ardupilot2/libraries/Filter/Butter.h
Gustavo Jose de Sousa a1af0c2051 Filter: standardize inclusion of libaries headers
This commit changes the way libraries headers are included in source files:

 - If the header is in the same directory the source belongs to, so the
 notation '#include ""' is used with the path relative to the directory
 containing the source.

 - If the header is outside the directory containing the source, then we use
 the notation '#include <>' with the path relative to libraries folder.

Some of the advantages of such approach:

 - Only one search path for libraries headers.

 - OSs like Windows may have a better lookup time.
2015-08-11 16:38:24 +10:00

112 lines
4.0 KiB
C++

#ifndef __FILTER_BUTTER_H__
#define __FILTER_BUTTER_H__
#include <AP_HAL/AP_HAL.h>
template <typename Coefficients>
class Butter2
{
public:
float filter(float input)
{
float newhist = input + Coefficients::A1*hist[1] + Coefficients::A2*hist[0];
float ret = (newhist + 2*hist[1] + hist[0])/Coefficients::GAIN;
hist[0] = hist[1]; hist[1] = newhist;
return ret;
}
private:
float hist[2];
};
struct butter100_025_coeffs
{
static constexpr float A1 = 1.9777864838f;
static constexpr float A2 = -0.9780305085f;
static constexpr float GAIN = 1.639178228e+04f;
};
typedef Butter2<butter100_025_coeffs> butter100hz0_25; //100hz sample, 0.25hz fcut
typedef Butter2<butter100_025_coeffs> butter50hz0_125; //50hz sample, 0.125hz fcut
typedef Butter2<butter100_025_coeffs> butter10hz0_025; //10hz sample, 0.025hz fcut
struct butter100_05_coeffs
{
static constexpr float A1 = 1.9555782403f;
static constexpr float A2 = -0.9565436765f;
static constexpr float GAIN = 4.143204922e+03f;
};
typedef Butter2<butter100_05_coeffs> butter100hz0_5; //100hz sample, 0.5hz fcut
typedef Butter2<butter100_05_coeffs> butter50hz0_25; //50hz sample, 0.25hz fcut
typedef Butter2<butter100_05_coeffs> butter10hz0_05; //10hz sample, 0.05hz fcut
struct butter100_1_coeffs
{
static constexpr float A1 = 1.9111970674f;
static constexpr float A2 = -0.9149758348f;
static constexpr float GAIN = 1.058546241e+03f;
};
typedef Butter2<butter100_1_coeffs> butter100hz1_0; //100hz sample, 1hz fcut
typedef Butter2<butter100_1_coeffs> butter50hz0_5; //50hz sample, 0.5hz fcut
typedef Butter2<butter100_1_coeffs> butter10hz0_1; //10hz sample, 0.1hz fcut
struct butter100_1_5_coeffs
{
static constexpr float A1 = 1.8668922797f;
static constexpr float A2 = -0.8752145483f;
static constexpr float GAIN = 4.806381793e+02f;
};
typedef Butter2<butter100_1_5_coeffs> butter100hz1_5; //100hz sample, 1.5hz fcut
typedef Butter2<butter100_1_5_coeffs> butter50hz0_75; //50hz sample, 0.75hz fcut
typedef Butter2<butter100_1_5_coeffs> butter10hz0_15; //10hz sample, 0.15hz fcut
struct butter100_2_coeffs
{
static constexpr float A1 = 1.8226949252f;
static constexpr float A2 = -0.8371816513f;
static constexpr float GAIN = 2.761148367e+02f;
};
typedef Butter2<butter100_2_coeffs> butter100hz2_0; //100hz sample, 2hz fcut
typedef Butter2<butter100_2_coeffs> butter50hz1_0; //50hz sample, 1hz fcut
typedef Butter2<butter100_2_coeffs> butter10hz0_2; //10hz sample, 0.2hz fcut
struct butter100_3_coeffs
{
static constexpr float A1 = 1.7347257688f;
static constexpr float A2 = -0.7660066009f;
static constexpr float GAIN = 1.278738361e+02f;
};
typedef Butter2<butter100_3_coeffs> butter100hz3_0; //100hz sample, 3hz fcut
typedef Butter2<butter100_3_coeffs> butter50hz1_5; //50hz sample, 1.5hz fcut
typedef Butter2<butter100_3_coeffs> butter10hz0_3; //10hz sample, 0.3hz fcut
struct butter100_4_coeffs
{
static constexpr float A1 = 1.6474599811f;
static constexpr float A2 = -0.7008967812f;
static constexpr float GAIN = 7.485478157e+01f;
};
typedef Butter2<butter100_4_coeffs> butter100hz4_0; //100hz sample, 4hz fcut
typedef Butter2<butter100_4_coeffs> butter50hz2_0; //50hz sample, 2hz fcut
typedef Butter2<butter100_4_coeffs> butter10hz0_4; //10hz sample, .4hz fcut
struct butter100_8_coeffs
{
static constexpr float A1 = 1.3072850288f;
static constexpr float A2 = -0.4918122372f;
static constexpr float GAIN = 2.167702007e+01f;
};
typedef Butter2<butter100_8_coeffs> butter100hz8_0; //100hz sample, 8hz fcut
typedef Butter2<butter100_8_coeffs> butter50hz4_0; //50hz sample, 4hz fcut
typedef Butter2<butter100_8_coeffs> butter10hz0_8; //10hz sample, .8hz fcut
struct butter50_8_coeffs
{
static constexpr float A1 = 0.6710290908f;
static constexpr float A2 = -0.2523246263f;
static constexpr float GAIN = 6.881181354e+00f;
};
typedef Butter2<butter50_8_coeffs> butter50hz8_0; //50hz sample, 8hz fcut
typedef Butter2<butter50_8_coeffs> butter10hz1_6; //10hz sample, 1.6hz fcut
#endif // __FILTER_BUTTER_H__