/* * Copyright © 2009 Keith Packard * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #ifndef AO_FLIGHT_TEST #include "ao.h" #endif #ifndef HAS_ACCEL #error Please define HAS_ACCEL #endif #ifndef HAS_GPS #error Please define HAS_GPS #endif #ifndef HAS_USB #error Please define HAS_USB #endif /* Main flight thread. */ __pdata enum ao_flight_state ao_flight_state; /* current flight state */ __pdata uint16_t ao_launch_tick; /* time of launch detect */ /* * track min/max data over a long interval to detect * resting */ __pdata uint16_t ao_interval_end; __pdata int16_t ao_interval_min_height; __pdata int16_t ao_interval_max_height; __pdata uint8_t ao_flight_force_idle; /* We also have a clock, which can be used to sanity check things in * case of other failures */ #define BOOST_TICKS_MAX AO_SEC_TO_TICKS(15) /* Landing is detected by getting constant readings from both pressure and accelerometer * for a fairly long time (AO_INTERVAL_TICKS) */ #define AO_INTERVAL_TICKS AO_SEC_TO_TICKS(10) #define abs(a) ((a) < 0 ? -(a) : (a)) void ao_flight(void) { ao_sample_init(); ao_flight_state = ao_flight_startup; for (;;) { /* * Process ADC samples, just looping * until the sensors are calibrated. */ if (!ao_sample()) continue; switch (ao_flight_state) { case ao_flight_startup: /* Check to see what mode we should go to. * - Invalid mode if accel cal appears to be out * - pad mode if we're upright, * - idle mode otherwise */ #if HAS_ACCEL if (ao_config.accel_plus_g == 0 || ao_config.accel_minus_g == 0 || ao_ground_accel < ao_config.accel_plus_g - ACCEL_NOSE_UP || ao_ground_accel > ao_config.accel_minus_g + ACCEL_NOSE_UP) { /* Detected an accel value outside -1.5g to 1.5g * (or uncalibrated values), so we go into invalid mode */ ao_flight_state = ao_flight_invalid; } else #endif if (!ao_flight_force_idle #if HAS_ACCEL && ao_ground_accel < ao_config.accel_plus_g + ACCEL_NOSE_UP #endif ) { /* Set pad mode - we can fly! */ ao_flight_state = ao_flight_pad; #if HAS_USB /* Disable the USB controller in flight mode * to save power */ ao_usb_disable(); #endif /* Disable packet mode in pad state */ ao_packet_slave_stop(); /* Turn on telemetry system */ ao_rdf_set(1); ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_PAD); /* signal successful initialization by turning off the LED */ ao_led_off(AO_LED_RED); } else { /* Set idle mode */ ao_flight_state = ao_flight_idle; /* signal successful initialization by turning off the LED */ ao_led_off(AO_LED_RED); } /* wakeup threads due to state change */ ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); break; case ao_flight_pad: /* pad to boost: * * barometer: > 20m vertical motion * OR * accelerometer: > 2g AND velocity > 5m/s * * The accelerometer should always detect motion before * the barometer, but we use both to make sure this * transition is detected. If the device * doesn't have an accelerometer, then ignore the * speed and acceleration as they are quite noisy * on the pad. */ if (ao_height > AO_M_TO_HEIGHT(20) #if HAS_ACCEL || (ao_accel > AO_MSS_TO_ACCEL(20) && ao_speed > AO_MS_TO_SPEED(5)) #endif ) { ao_flight_state = ao_flight_boost; ao_launch_tick = ao_sample_tick; /* start logging data */ ao_log_start(); /* Increase telemetry rate */ ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_FLIGHT); /* disable RDF beacon */ ao_rdf_set(0); #if HAS_GPS /* Record current GPS position by waking up GPS log tasks */ ao_wakeup(&ao_gps_data); ao_wakeup(&ao_gps_tracking_data); #endif ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } break; case ao_flight_boost: /* boost to fast: * * accelerometer: start to fall at > 1/4 G * OR * time: boost for more than 15 seconds * * Detects motor burn out by the switch from acceleration to * deceleration, or by waiting until the maximum burn duration * (15 seconds) has past. */ if ((ao_accel < AO_MSS_TO_ACCEL(-2.5) && ao_height > AO_M_TO_HEIGHT(100)) || (int16_t) (ao_sample_tick - ao_launch_tick) > BOOST_TICKS_MAX) { #if HAS_ACCEL ao_flight_state = ao_flight_fast; #else ao_flight_state = ao_flight_coast; #endif ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } break; #if HAS_ACCEL case ao_flight_fast: /* * This is essentially the same as coast, * but the barometer is being ignored as * it may be unreliable. */ if (ao_speed < AO_MS_TO_SPEED(AO_MAX_BARO_SPEED)) { ao_flight_state = ao_flight_coast; ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } break; #endif case ao_flight_coast: /* apogee detect: coast to drogue deploy: * * speed: < 0 * * Also make sure the model altitude is tracking * the measured altitude reasonably closely; otherwise * we're probably transsonic. */ if (ao_speed < 0 #if !HAS_ACCEL && (ao_sample_alt >= AO_MAX_BARO_HEIGHT || ao_error_h_sq_avg < 100) #endif ) { /* ignite the drogue charge */ ao_ignite(ao_igniter_drogue); /* slow down the telemetry system */ ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_RECOVER); /* Turn the RDF beacon back on */ ao_rdf_set(1); /* and enter drogue state */ ao_flight_state = ao_flight_drogue; ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } break; case ao_flight_drogue: /* drogue to main deploy: * * barometer: reach main deploy altitude * * Would like to use the accelerometer for this test, but * the orientation of the flight computer is unknown after * drogue deploy, so we ignore it. Could also detect * high descent rate using the pressure sensor to * recognize drogue deploy failure and eject the main * at that point. Perhaps also use the drogue sense lines * to notice continutity? */ if (ao_height <= ao_config.main_deploy) { ao_ignite(ao_igniter_main); /* * Start recording min/max height * to figure out when the rocket has landed */ /* initialize interval values */ ao_interval_end = ao_sample_tick + AO_INTERVAL_TICKS; ao_interval_min_height = ao_interval_max_height = ao_avg_height; ao_flight_state = ao_flight_main; ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } break; /* fall through... */ case ao_flight_main: /* main to land: * * barometer: altitude stable */ if (ao_avg_height < ao_interval_min_height) ao_interval_min_height = ao_avg_height; if (ao_avg_height > ao_interval_max_height) ao_interval_max_height = ao_avg_height; if ((int16_t) (ao_sample_tick - ao_interval_end) >= 0) { if (ao_interval_max_height - ao_interval_min_height <= AO_M_TO_HEIGHT(4)) { ao_flight_state = ao_flight_landed; /* turn off the ADC capture */ ao_timer_set_adc_interval(0); ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } ao_interval_min_height = ao_interval_max_height = ao_avg_height; ao_interval_end = ao_sample_tick + AO_INTERVAL_TICKS; } break; case ao_flight_landed: break; } } } static __xdata struct ao_task flight_task; void ao_flight_init(void) { ao_flight_state = ao_flight_startup; ao_add_task(&flight_task, ao_flight, "flight"); }