filter_func.h

00001 #ifndef __FILTER_FUNCTIONS_H__
00002 #define __FILTER_FUNCTIONS_H__
00003 
00004 #include <math.h>
00005 #include "mbed.h"
00006 
00007 typedef enum _BIQUADTYPE{
00008     FILTER_LPF  =   1,
00009     FILTER_HPF  =   2,
00010     FILTER_BPF  =   3,
00011     FILTER_NF   =   4   
00012 } BIQUADTYPE;
00013 
00014 typedef struct _STCOMPFILTER{
00015     float   _int;
00016     float   _adj;
00017     float   _adj_temp;
00018     float   _param;
00019 } STCOMPFILTER;
00020 
00021 typedef struct _STBIQUADFILTER{
00022     float   in[2];      // input
00023     float   out[2];     // output
00024     float   a[3];       // coefficient A
00025     float   b[3];       // coefficient B
00026 } STBIQUADFILTER;
00027 
00028 // complimentary filter
00029 void init_comp_filter( STCOMPFILTER* filter, float param );
00030 void proc_comp_filter( STCOMPFILTER* filter, float dt, float angle_raw, float angle_vec_raw, float* angle, float* angle_vec );
00031 
00032 // BiQuad filter
00033 void  init_biquad_filter( STBIQUADFILTER* filter, float freq_sample, float freq, float param, BIQUADTYPE filter_pattern );
00034 float proc_biquad_filter( STBIQUADFILTER* filter, float input );
00035 
00036 #endif