ardupilot/libraries/AP_Math/examples/rotations/rotations.pde

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
//
// Unit tests for the AP_Math rotations code
//
#include <stdlib.h>
#include <AP_Common.h>
#include <AP_Progmem.h>
#include <AP_Param.h>
#include <AP_HAL.h>
#include <AP_Math.h>
#include <AP_Declination.h> // ArduPilot Mega Declination Helper Library

#include <AP_HAL_AVR.h>
const AP_HAL::HAL& hal = AP_HAL_BOARD_DRIVER;

// standard rotation matrices (these are the originals from the old code)
#define MATRIX_ROTATION_NONE               Matrix3f(1, 0, 0, 0, 1, 0, 0,0, 1)
#define MATRIX_ROTATION_YAW_45             Matrix3f(0.70710678, -0.70710678, 0, 0.70710678, 0.70710678, 0, 0, 0, 1)
#define MATRIX_ROTATION_YAW_90             Matrix3f(0, -1, 0, 1, 0, 0, 0, 0, 1)
#define MATRIX_ROTATION_YAW_135            Matrix3f(-0.70710678, -0.70710678, 0, 0.70710678, -0.70710678, 0, 0, 0, 1)
#define MATRIX_ROTATION_YAW_180            Matrix3f(-1, 0, 0, 0, -1, 0, 0, 0, 1)
#define MATRIX_ROTATION_YAW_225            Matrix3f(-0.70710678, 0.70710678, 0, -0.70710678, -0.70710678, 0, 0, 0, 1)
#define MATRIX_ROTATION_YAW_270            Matrix3f(0, 1, 0, -1, 0, 0, 0, 0, 1)
#define MATRIX_ROTATION_YAW_315            Matrix3f(0.70710678, 0.70710678, 0, -0.70710678, 0.70710678, 0, 0, 0, 1)
#define MATRIX_ROTATION_ROLL_180           Matrix3f(1, 0, 0, 0, -1, 0, 0, 0, -1)
#define MATRIX_ROTATION_ROLL_180_YAW_45    Matrix3f(0.70710678, 0.70710678, 0, 0.70710678, -0.70710678, 0, 0, 0, -1)
#define MATRIX_ROTATION_ROLL_180_YAW_90    Matrix3f(0, 1, 0, 1, 0, 0, 0, 0, -1)
#define MATRIX_ROTATION_ROLL_180_YAW_135   Matrix3f(-0.70710678, 0.70710678, 0, 0.70710678, 0.70710678, 0, 0, 0, -1)
#define MATRIX_ROTATION_PITCH_180          Matrix3f(-1, 0, 0, 0, 1, 0, 0, 0, -1)
#define MATRIX_ROTATION_ROLL_180_YAW_225   Matrix3f(-0.70710678, -0.70710678, 0, -0.70710678, 0.70710678, 0, 0, 0, -1)
#define MATRIX_ROTATION_ROLL_180_YAW_270   Matrix3f(0, -1, 0, -1, 0, 0, 0, 0, -1)
#define MATRIX_ROTATION_ROLL_180_YAW_315   Matrix3f(0.70710678, -0.70710678, 0, -0.70710678, -0.70710678, 0, 0, 0, -1)

static void print_matrix(Matrix3f &m)
{
    hal.console->printf("[%.2f %.2f %.2f] [%.2f %.2f %.2f] [%.2f %.2f %.2f]\n",
                  m.a.x, m.a.y, m.a.z,
                  m.b.x, m.b.y, m.b.z,
                  m.c.x, m.c.y, m.c.z);
}

// test one matrix
static void test_matrix(enum Rotation rotation, Matrix3f m)
{
    Matrix3f m2, diff;
    const float accuracy = 1.0e-6;
    m2.rotation(rotation);
    diff = (m - m2);
    if (diff.a.length() > accuracy ||
        diff.b.length() > accuracy ||
        diff.c.length() > accuracy) {
        hal.console->printf("rotation matrix %u incorrect\n", (unsigned)rotation);
        print_matrix(m);
        print_matrix(m2);
    }
}

// test generation of rotation matrices
static void test_matrices(void)
{
    hal.console->println("testing rotation matrices\n");
    test_matrix(ROTATION_NONE, MATRIX_ROTATION_NONE);
    test_matrix(ROTATION_YAW_45, MATRIX_ROTATION_YAW_45);
    test_matrix(ROTATION_YAW_90, MATRIX_ROTATION_YAW_90);
    test_matrix(ROTATION_YAW_135, MATRIX_ROTATION_YAW_135);
    test_matrix(ROTATION_YAW_180, MATRIX_ROTATION_YAW_180);
    test_matrix(ROTATION_YAW_225, MATRIX_ROTATION_YAW_225);
    test_matrix(ROTATION_YAW_270, MATRIX_ROTATION_YAW_270);
    test_matrix(ROTATION_YAW_315, MATRIX_ROTATION_YAW_315);
    test_matrix(ROTATION_ROLL_180, MATRIX_ROTATION_ROLL_180);
    test_matrix(ROTATION_ROLL_180_YAW_45, MATRIX_ROTATION_ROLL_180_YAW_45);
    test_matrix(ROTATION_ROLL_180_YAW_90, MATRIX_ROTATION_ROLL_180_YAW_90);
    test_matrix(ROTATION_ROLL_180_YAW_135, MATRIX_ROTATION_ROLL_180_YAW_135);
    test_matrix(ROTATION_PITCH_180, MATRIX_ROTATION_PITCH_180);
    test_matrix(ROTATION_ROLL_180_YAW_225, MATRIX_ROTATION_ROLL_180_YAW_225);
    test_matrix(ROTATION_ROLL_180_YAW_270, MATRIX_ROTATION_ROLL_180_YAW_270);
    test_matrix(ROTATION_ROLL_180_YAW_315, MATRIX_ROTATION_ROLL_180_YAW_315);
}

// test rotation of vectors
static void test_vector(enum Rotation rotation, Vector3f v1, bool show=true)
{
    Vector3f v2, diff;
    Matrix3f m;
    v2 = v1;
    m.rotation(rotation);
    v1.rotate(rotation);
    v2 = m * v2;
    diff = v1 - v2;
    if (diff.length() > 1.0e-6) {
        hal.console->printf("rotation vector %u incorrect\n", (unsigned)rotation);
        hal.console->printf("%u  %f %f %f\n",
                      (unsigned)rotation,
                      v2.x, v2.y, v2.z);
    }
    if (show) {
        hal.console->printf("%u  %f %f %f\n",
                      (unsigned)rotation,
                      v1.x, v1.y, v1.z);
    }
}

// generate a random float between -1 and 1
static float rand_num(void)
{
    float ret = ((unsigned)random()) % 2000000;
    return (ret - 1.0e6) / 1.0e6;
}

// test rotation of vectors
static void test_vector(enum Rotation rotation)
{
    uint8_t i;

    Vector3f v1;
    v1.x = 1;
    v1.y = 2;
    v1.z = 3;
    test_vector(rotation, v1);

    for (i=0; i<10; i++) {
        v1.x = rand_num();
        v1.y = rand_num();
        v1.z = rand_num();
        test_vector(rotation, v1, false);
    }
}

// test rotation of vectors
static void test_vectors(void)
{
    hal.console->println("testing rotation of vectors\n");
    test_vector(ROTATION_NONE);
    test_vector(ROTATION_YAW_45);
    test_vector(ROTATION_YAW_90);
    test_vector(ROTATION_YAW_135);
    test_vector(ROTATION_YAW_180);
    test_vector(ROTATION_YAW_225);
    test_vector(ROTATION_YAW_270);
    test_vector(ROTATION_YAW_315);
    test_vector(ROTATION_ROLL_180);
    test_vector(ROTATION_ROLL_180_YAW_45);
    test_vector(ROTATION_ROLL_180_YAW_90);
    test_vector(ROTATION_ROLL_180_YAW_135);
    test_vector(ROTATION_PITCH_180);
    test_vector(ROTATION_ROLL_180_YAW_225);
    test_vector(ROTATION_ROLL_180_YAW_270);
    test_vector(ROTATION_ROLL_180_YAW_315);
}


// test combinations of rotations
static void test_combinations(void)
{
    enum Rotation r1, r2, r3;
    bool found;

    for (r1=ROTATION_NONE; r1<ROTATION_MAX;
         r1 = (enum Rotation)((uint8_t)r1+1)) {
        for (r2=ROTATION_NONE; r2<ROTATION_MAX;
             r2 = (enum Rotation)((uint8_t)r2+1)) {
            r3 = rotation_combination(r1, r2, &found);
            if (found) {
                hal.console->printf("rotation: %u + %u -> %u\n",
                              (unsigned)r1, (unsigned)r2, (unsigned)r3);
            } else {
                hal.console->printf("ERROR rotation: no combination for %u + %u\n",
                              (unsigned)r1, (unsigned)r2);
            }
        }
    }
}

// test rotation method accuracy
static void test_rotation_accuracy(void)
{
    Matrix3f attitude;
    Vector3f small_rotation;
    float roll, pitch, yaw;
    int16_t i;
    float rot_angle;

    hal.console->println_P(PSTR("\nRotation method accuracy:"));

    for( i=0; i<90; i++ ) {

        // reset initial attitude
        attitude.from_euler(0,0,0);

        // calculate small rotation vector
        rot_angle = ToRad(i);
        small_rotation = Vector3f(0,0,rot_angle);

        // apply small rotation
        attitude.rotate(small_rotation);

        // get resulting attitude's euler angles
        attitude.to_euler(&roll, &pitch, &yaw);

        // display results
        hal.console->printf_P(
                PSTR("actual angle: %d\tcalculated angle:%4.2f\n"),
                (int)i,ToDeg(yaw));
    }
}

/*
 *  rotation tests
 */
void setup(void)
{
    hal.console->println("rotation unit tests\n");
    test_matrices();
    test_vectors();
    test_combinations();
    test_rotation_accuracy();
    hal.console->println("rotation unit tests done\n");
}

void loop(void) {}

AP_HAL_MAIN();