Subversion Repositories FlightCtrl

Rev

Details | Last modification | View Log | RSS feed

Rev Author Line No. Line
375 osiair 1 
/*
2 
 
3 
Copyright 2007, Niklas Nold
4 
 
5 
This program (files math.c and math.h) is free software; you can redistribute it and/or modify
6 
it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation;
7 
either version 3 of the License, or (at your option) any later version.  
8 
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
9 
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10 
GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License
11 
along with this program. If not, see <http://www.gnu.org/licenses/>.
12 
 
13 
Please note: All the other files for the project "Mikrokopter" by H. Buss are under the license (license_buss.txt) published by www.mikrokopter.de
14 
*/
15 
 
16 
#include "main.h"
17 
 
18 
 
19 
const uint8_t pgm_atan[270] PROGMEM = {0,1,2,3,5,6,7,8,9,10,11,12,13,15,16,17,18,19,20,21,22,23,24,25,26,27,27,28,29,30,31,32,33,33,34,35,36,37,37,38,39,39,40,41,41,42,43,43,44,44,45,46,46,47,47,48,48,49,49,50,50,51,51,52,52,52,53,53,54,54,54,55,55,56,56,56,57,57,57,58,58,58,59,59,59,60,60,60,60,61,61,61,61,62,62,62,62,63,63,63,63,64,64,64,64,65,65,65,65,65,66,66,66,66,66,67,67,67,67,67,67,68,68,68,68,68,68,69,69,69,69,69,69,69,70,70,70,70,70,70,70,70,71,71,71,71,71,71,71,71,72,72,72,72,72,72,72,72,72,73,73,73,73,73,73,73,73,73,73,74,74,74,74,74,74,74,74,74,74,74,74,75,75,75,75,75,75,75,75,75,75,75,75,75,76,76,76,76,76,76,76,76,76,76,76,76,76,76,76,77,77,77,77,77,77,77,77,77,77,77,77,77,77,77,77,77,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79,79};
20 
 
21 
// Arkustangens2 im Gradmaß
22 
signed int atan2_i(signed int x,  signed int y)
23 
{
24 
        int i,angle;
25 
        int8_t m;
26 
 
27 
        if (!x && !y) return 0;         //atan2 = 0 für x und y = 0
28 
 
29 
        if (y < 0) m=-1;
30 
        else m=1;
31 
 
32 
        if (x==0) return (90*m);                // atan2 = 90° für x = 0
33 
 
34 
        i = abs(((float)y / x) * 50);           // Berechne i für die Lookup table (Schrittweite atan(x) ist 0.02 -> *50)
35 
 
36 
        if (i<270) angle = pgm_read_byte(&pgm_atan[i]); // Lookup für 1° bis 79°
37 
        else if (i>5750) angle = 90;                                            // Grenzwert ist 90°
38 
        else if (i>=1910) angle = 89;                                           // 89° bis 80° über Wertebereiche
39 
        else if (i>=1150) angle = 88;
40 
        else if (i>=820) angle = 87;
41 
        else if (i>=640) angle = 86;
42 
        else if (i>=520) angle = 85;
43 
        else if (i>=440) angle = 84;
44 
        else if (i>=380) angle = 83;
45 
        else if (i>=335) angle = 82;
46 
        else if (i>=299) angle = 81;
47 
        else angle = 80; // (i>=270)
48 
 
49 
        if (x > 0) return (angle*m);    // Quadrant I und IV
50 
        else if ((x < 0) && (y >= 0)) return ((angle*-1) + 180);        // Quadrant II
51 
        else return (angle - 180); // x < 0 && y < 0    Quadrant III
52 
}
53 
 
54 
 
55 
 
56 
 
57 
 
58 
const float pgm_sinus_f [91] PROGMEM = {0.000,0.017,0.035,0.052,0.070,0.087,0.105,0.122,0.139,0.156,0.174,0.191,0.208,0.225,0.242,0.259,0.276,0.292,0.309,0.326,0.342,0.358,0.375,0.391,0.407,0.423,0.438,0.454,0.469,0.485,0.500,0.515,0.530,0.545,0.559,0.574,0.588,0.602,0.616,0.629,0.643,0.656,0.669,0.682,0.695,0.707,0.719,0.731,0.743,0.755,0.766,0.777,0.788,0.799,0.809,0.819,0.829,0.839,0.848,0.857,0.866,0.875,0.883,0.891,0.899,0.906,0.914,0.921,0.927,0.934,0.940,0.946,0.951,0.956,0.961,0.966,0.970,0.974,0.978,0.982,0.985,0.988,0.990,0.993,0.995,0.996,0.998,0.999,0.999,1.000,1.000};
59 
 
60 
inline float pgm_read_float(const float *addr)
61 
{      
62 
        union
63 
        {
64 
                uint16_t i[2];  // 2 16-bit-Worte
65 
                float f;
66 
        } u;
67 
 
68 
        u.i[0]=pgm_read_word((PGM_P)addr);
69 
        u.i[1]=pgm_read_word((PGM_P)addr+2);
70 
 
71 
        return u.f;
72 
}
73 
 
74 
// Kosinusfunktion im Gradmaß
75 
float cos_f(signed int winkel)
76 
{
77 
 return (sin_f(90-winkel));
78 
}
79 
 
80 
// Sinusfunktion im Gradmaß
81 
float sin_f(signed int winkel)
82 
{
83 
 short int m,n;
84 
 float sinus;
85 
 
86 
 //winkel = winkel % 360;
87 
 
88 
 if (winkel < 0)
89 
 {
90 
        m = -1;
91 
        winkel = abs(winkel);
92 
 }
93 
 else m = +1;
94 
 
95 
 // Quadranten auswerten
96 
 if ((winkel > 90 ) && (winkel <= 180)) {winkel = 180 - winkel; n = 1;}
97 
 else if ((winkel > 180 ) && (winkel <= 270)) {winkel = winkel - 180; n = -1;}
98 
 else if ((winkel > 270) && (winkel <= 360)) {winkel = 360 - winkel; n = -1;}
99 
 else n = 1; //0 - 90 Grad
100 
 
101 
sinus = pgm_read_float(&pgm_sinus_f[winkel]);
102 
 
103 
return (sinus*m*n);
104 
}
105 
 
106 
 
107 
const uint8_t pgm_asin[201] PROGMEM = {0,0,1,1,1,1,2,2,2,3,3,3,3,4,4,4,5,5,5,5,6,6,6,7,7,7,7,8,8,8,9,9,9,9,10,10,10,11,11,11,12,12,12,12,13,13,13,14,14,14,14,15,15,15,16,16,16,17,17,17,17,18,18,18,19,19,19,20,20,20,20,21,21,21,22,22,22,23,23,23,24,24,24,25,25,25,25,26,26,26,27,27,27,28,28,28,29,29,29,30,30,30,31,31,31,32,32,32,33,33,33,34,34,34,35,35,35,36,36,37,37,37,38,38,38,39,39,39,40,40,41,41,41,42,42,42,43,43,44,44,44,45,45,46,46,46,47,47,48,48,49,49,49,50,50,51,51,52,52,53,53,54,54,55,55,56,56,57,57,58,58,59,59,60,60,61,62,62,63,64,64,65,66,66,67,68,68,69,70,71,72,73,74,75,76,77,79,80,82,84,90};
108 
 
109 
// Akurssinusfunktion im Gradmaß
110 
int8_t asin_i(signed int i)
111 
{
112 
        signed char m;
113 
 
114 
        if (i < 0) {m=-1;i=abs(i);}
115 
        else m=1;
116 
 
117 
        return (pgm_read_byte(&pgm_asin[i]) * m);
118 
}