diff options
Diffstat (limited to 'src/core/ao_flight.c')
| -rw-r--r-- | src/core/ao_flight.c | 315 | 
1 files changed, 315 insertions, 0 deletions
| diff --git a/src/core/ao_flight.c b/src/core/ao_flight.c new file mode 100644 index 00000000..85c1825b --- /dev/null +++ b/src/core/ao_flight.c @@ -0,0 +1,315 @@ +/* + * Copyright © 2009 Keith Packard <keithp@keithp.com> + * + * 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"); +} | 
