// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- //**************************************************************** // Function that will calculate the desired direction to fly and distance //**************************************************************** static void navigate() { // waypoint distance from plane in cm // --------------------------------------- wp_distance = get_distance(¤t_loc, &next_WP); home_distance = get_distance(¤t_loc, &home); // target_bearing is where we should be heading // -------------------------------------------- target_bearing = get_bearing(¤t_loc, &next_WP); home_to_copter_bearing = get_bearing(&home, ¤t_loc); } static bool check_missed_wp() { int32_t temp; temp = target_bearing - original_target_bearing; temp = wrap_180(temp); return (abs(temp) > 10000); // we passed the waypoint by 100 degrees } // ------------------------------ static void calc_XY_velocity(){ static int32_t last_longitude = 0; static int32_t last_latitude = 0; // called after GPS read // offset calculation of GPS speed: // used for estimations below 1.5m/s // y_GPS_speed positve = Up // x_GPS_speed positve = Right // initialise last_longitude and last_latitude if( last_longitude == 0 && last_latitude == 0 ) { last_longitude = g_gps->longitude; last_latitude = g_gps->latitude; } // this speed is ~ in cm because we are using 10^7 numbers from GPS float tmp = 1.0/dTnav; x_actual_speed = (float)(g_gps->longitude - last_longitude) * scaleLongDown * tmp; y_actual_speed = (float)(g_gps->latitude - last_latitude) * tmp; last_longitude = g_gps->longitude; last_latitude = g_gps->latitude; if(g_gps->ground_speed > 150){ float temp = radians((float)g_gps->ground_course/100.0); x_actual_speed = (float)g_gps->ground_speed * sin(temp); y_actual_speed = (float)g_gps->ground_speed * cos(temp); } #if INERTIAL_NAV == ENABLED // inertial_nav xy_error_correction(); #endif current_loc.lng = xLeadFilter.get_position(g_gps->longitude, x_actual_speed); current_loc.lat = yLeadFilter.get_position(g_gps->latitude, y_actual_speed); } static void calc_location_error(struct Location *next_loc) { /* Becuase we are using lat and lon to do our distance errors here's a quick chart: 100 = 1m 1000 = 11m = 36 feet 1800 = 19.80m = 60 feet 3000 = 33m 10000 = 111m */ // X Error long_error = (float)(next_loc->lng - current_loc.lng) * scaleLongDown; // 500 - 0 = 500 Go East // Y Error lat_error = next_loc->lat - current_loc.lat; // 500 - 0 = 500 Go North } #define NAV_ERR_MAX 600 #define NAV_RATE_ERR_MAX 250 static void calc_loiter(int x_error, int y_error) { int32_t p,i,d; // used to capture pid values for logging int32_t output; int32_t x_target_speed, y_target_speed; // East / West x_target_speed = g.pi_loiter_lon.get_p(x_error); // calculate desired speed from lon error #if LOGGING_ENABLED == ENABLED // log output if PID logging is on and we are tuning the yaw if( g.log_bitmask & MASK_LOG_PID && (g.radio_tuning == CH6_LOITER_KP || g.radio_tuning == CH6_LOITER_KI) ) { Log_Write_PID(CH6_LOITER_KP, x_error, x_target_speed, 0, 0, x_target_speed, tuning_value); } #endif // calculate rate error #if INERTIAL_NAV == ENABLED x_rate_error = x_target_speed - accels_velocity.x; // calc the speed error #else x_rate_error = x_target_speed - x_actual_speed; // calc the speed error #endif p = g.pid_loiter_rate_lon.get_p(x_rate_error); i = g.pid_loiter_rate_lon.get_i(x_rate_error + x_error, dTnav); d = g.pid_loiter_rate_lon.get_d(x_error, dTnav); d = constrain(d, -2000, 2000); // get rid of noise if(abs(x_actual_speed) < 50){ d = 0; } output = p + i + d; nav_lon = constrain(output, -3000, 3000); // 30° #if LOGGING_ENABLED == ENABLED // log output if PID logging is on and we are tuning the yaw if( g.log_bitmask & MASK_LOG_PID && (g.radio_tuning == CH6_LOITER_RATE_KP || g.radio_tuning == CH6_LOITER_RATE_KI || g.radio_tuning == CH6_LOITER_RATE_KD) ) { Log_Write_PID(CH6_LOITER_RATE_KP, x_rate_error, p, i, d, nav_lon, tuning_value); } #endif // North / South y_target_speed = g.pi_loiter_lat.get_p(y_error); // calculate desired speed from lat error #if LOGGING_ENABLED == ENABLED // log output if PID logging is on and we are tuning the yaw if( g.log_bitmask & MASK_LOG_PID && (g.radio_tuning == CH6_LOITER_KP || g.radio_tuning == CH6_LOITER_KI) ) { Log_Write_PID(CH6_LOITER_KP+100, y_error, y_target_speed, 0, 0, y_target_speed, tuning_value); } #endif // calculate rate error #if INERTIAL_NAV == ENABLED y_rate_error = y_target_speed - accels_velocity.y; // calc the speed error #else y_rate_error = y_target_speed - y_actual_speed; // calc the speed error #endif p = g.pid_loiter_rate_lat.get_p(y_rate_error); i = g.pid_loiter_rate_lat.get_i(y_rate_error + y_error, dTnav); d = g.pid_loiter_rate_lat.get_d(y_error, dTnav); d = constrain(d, -2000, 2000); // get rid of noise if(abs(y_actual_speed) < 50){ d = 0; } output = p + i + d; nav_lat = constrain(output, -3000, 3000); // 30° #if LOGGING_ENABLED == ENABLED // log output if PID logging is on and we are tuning the yaw if( g.log_bitmask & MASK_LOG_PID && (g.radio_tuning == CH6_LOITER_RATE_KP || g.radio_tuning == CH6_LOITER_RATE_KI || g.radio_tuning == CH6_LOITER_RATE_KD) ) { Log_Write_PID(CH6_LOITER_RATE_KP+100, y_rate_error, p, i, d, nav_lat, tuning_value); } #endif // copy over I term to Nav_Rate g.pid_nav_lon.set_integrator(g.pid_loiter_rate_lon.get_integrator()); g.pid_nav_lat.set_integrator(g.pid_loiter_rate_lat.get_integrator()); } static void calc_nav_rate(int max_speed) { float temp, temp_x, temp_y; // push us towards the original track update_crosstrack(); int16_t cross_speed = crosstrack_error * -g.crosstrack_gain; // scale down crosstrack_error in cm // XXX replace above with crosstrack gain. cross_speed = constrain(cross_speed, -200, 200); // rotate by 90 to deal with trig functions temp = (9000l - target_bearing) * RADX100; temp_x = cos(temp); temp_y = sin(temp); // rotate desired spped vector: int16_t x_target_speed = max_speed * temp_x - cross_speed * temp_y; int16_t y_target_speed = cross_speed * temp_x + max_speed * temp_y; // East / West x_rate_error = x_target_speed - x_actual_speed; // 413 x_rate_error = constrain(x_rate_error, -1000, 1000); nav_lon = g.pid_nav_lon.get_pid(x_rate_error, dTnav); nav_lon = constrain(nav_lon, -3000, 3000); // North / South y_rate_error = y_target_speed - y_actual_speed; // 413 y_rate_error = constrain(y_rate_error, -1000, 1000); // added a rate error limit to keep pitching down to a minimum nav_lat = g.pid_nav_lat.get_pid(y_rate_error, dTnav); nav_lat = constrain(nav_lat, -3000, 3000); // copy over I term to Loiter_Rate g.pid_loiter_rate_lon.set_integrator(g.pid_nav_lon.get_integrator()); g.pid_loiter_rate_lat.set_integrator(g.pid_nav_lat.get_integrator()); } // this calculation rotates our World frame of reference to the copter's frame of reference // We use the DCM's matrix to precalculate these trig values at 50hz static void calc_loiter_pitch_roll() { //Serial.printf("ys %ld, cx %1.4f, _cx %1.4f | sy %1.4f, _sy %1.4f\n", dcm.yaw_sensor, cos_yaw_x, _cos_yaw_x, sin_yaw_y, _sin_yaw_y); // rotate the vector auto_roll = (float)nav_lon * sin_yaw_y - (float)nav_lat * cos_yaw_x; auto_pitch = (float)nav_lon * cos_yaw_x + (float)nav_lat * sin_yaw_y; // flip pitch because forward is negative auto_pitch = -auto_pitch; } static int16_t calc_desired_speed(int16_t max_speed, bool _slow) { /* |< WP Radius 0 1 2 3 4 5 6 7 8m ...|...|...|...|...|...|...|...| 100 | 200 300 400cm/s | +|+ |< we should slow to 1.5 m/s as we hit the target */ // max_speed is default 600 or 6m/s if(_slow){ max_speed = min(max_speed, wp_distance / 2); max_speed = max(max_speed, 0); }else{ max_speed = min(max_speed, wp_distance); max_speed = max(max_speed, WAYPOINT_SPEED_MIN); // go at least 100cm/s } // limit the ramp up of the speed // waypoint_speed_gov is reset to 0 at each new WP command if(max_speed > waypoint_speed_gov){ waypoint_speed_gov += (int)(100.0 * dTnav); // increase at .5/ms max_speed = waypoint_speed_gov; } return max_speed; } static void update_crosstrack(void) { // Crosstrack Error // ---------------- // If we are too far off or too close we don't do track following float temp = (target_bearing - original_target_bearing) * RADX100; crosstrack_error = sin(temp) * wp_distance; // Meters we are off track line } static int32_t get_altitude_error() { // Next_WP alt is our target alt // It changes based on climb rate // until it reaches the target_altitude return next_WP.alt - current_loc.alt; } static void clear_new_altitude() { alt_change_flag = REACHED_ALT; } static void force_new_altitude(int32_t _new_alt) { next_WP.alt = _new_alt; target_altitude = _new_alt; alt_change_flag = REACHED_ALT; } static void set_new_altitude(int32_t _new_alt) { if(_new_alt == current_loc.alt){ force_new_altitude(_new_alt); return; } // We start at the current location altitude and gradually change alt next_WP.alt = current_loc.alt; // for calculating the delta time alt_change_timer = millis(); // save the target altitude target_altitude = _new_alt; // reset our altitude integrator alt_change = 0; // save the original altitude original_altitude = current_loc.alt; // to decide if we have reached the target altitude if(target_altitude > original_altitude){ // we are below, going up alt_change_flag = ASCENDING; //Serial.printf("go up\n"); }else if(target_altitude < original_altitude){ // we are above, going down alt_change_flag = DESCENDING; //Serial.printf("go down\n"); }else{ // No Change alt_change_flag = REACHED_ALT; //Serial.printf("reached alt\n"); } //Serial.printf("new alt: %d Org alt: %d\n", target_altitude, original_altitude); } static int32_t get_new_altitude() { // returns a new next_WP.alt if(alt_change_flag == ASCENDING){ // we are below, going up if(current_loc.alt >= target_altitude){ alt_change_flag = REACHED_ALT; } // we shouldn't command past our target if(next_WP.alt >= target_altitude){ return target_altitude; } }else if (alt_change_flag == DESCENDING){ // we are above, going down if(current_loc.alt <= target_altitude) alt_change_flag = REACHED_ALT; // we shouldn't command past our target if(next_WP.alt <= target_altitude){ return target_altitude; } } // if we have reached our target altitude, return the target alt if(alt_change_flag == REACHED_ALT){ return target_altitude; } int32_t diff = abs(next_WP.alt - target_altitude); // scale is how we generate a desired rate from the elapsed time // a smaller scale means faster rates int8_t _scale = 4; if (next_WP.alt < target_altitude){ // we are below the target alt if(diff < 200){ _scale = 4; } else { _scale = 3; } }else { // we are above the target, going down if(diff < 400){ _scale = 5; } if(diff < 100){ _scale = 6; } } // we use the elapsed time as our altitude offset // 1000 = 1 sec // 1000 >> 4 = 64cm/s descent by default int32_t change = (millis() - alt_change_timer) >> _scale; if(alt_change_flag == ASCENDING){ alt_change += change; }else{ alt_change -= change; } // for generating delta time alt_change_timer = millis(); return original_altitude + alt_change; } static int32_t wrap_360(int32_t error) { if (error > 36000) error -= 36000; if (error < 0) error += 36000; return error; } static int32_t wrap_180(int32_t error) { if (error > 18000) error -= 36000; if (error < -18000) error += 36000; return error; } /* //static int32_t get_altitude_above_home(void) { // This is the altitude above the home location // The GPS gives us altitude at Sea Level // if you slope soar, you should see a negative number sometimes // ------------------------------------------------------------- return current_loc.alt - home.alt; } */ // distance is returned in cm static int32_t get_distance(struct Location *loc1, struct Location *loc2) { float dlat = (float)(loc2->lat - loc1->lat); float dlong = ((float)(loc2->lng - loc1->lng)) * scaleLongDown; dlong = sqrt(sq(dlat) + sq(dlong)) * 1.113195; return dlong; } /* //static int32_t get_alt_distance(struct Location *loc1, struct Location *loc2) { return abs(loc1->alt - loc2->alt); } */ static int32_t get_bearing(struct Location *loc1, struct Location *loc2) { int32_t off_x = loc2->lng - loc1->lng; int32_t off_y = (loc2->lat - loc1->lat) * scaleLongUp; int32_t bearing = 9000 + atan2(-off_y, off_x) * 5729.57795; if (bearing < 0) bearing += 36000; return bearing; }