+/*
+ * 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"
+#include <ao_log.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_boost_tick; /* time of launch detect */
+
+/*
+ * track min/max data over a long interval to detect
+ * resting
+ */
+static __data uint16_t ao_interval_end;
+static __data int16_t ao_interval_min_height;
+static __data int16_t ao_interval_max_height;
+static __data int16_t ao_coast_avg_accel;
+
+__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;
+
+#if HAS_RADIO
+ /* Turn on packet system in invalid mode on TeleMetrum */
+ ao_packet_slave_start();
+#endif
+ } 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
+
+#if !HAS_ACCEL
+ /* Disable packet mode in pad state on TeleMini */
+ ao_packet_slave_stop();
+#endif
+
+#if HAS_RADIO
+ /* Turn on telemetry system */
+ ao_rdf_set(1);
+ ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_PAD);
+#endif
+ /* signal successful initialization by turning off the LED */
+ ao_led_off(AO_LED_RED);
+ } else {
+ /* Set idle mode */
+ ao_flight_state = ao_flight_idle;
+
+#if HAS_ACCEL && HAS_RADIO
+ /* Turn on packet system in idle mode on TeleMetrum */
+ ao_packet_slave_start();
+#endif
+
+ /* 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_boost_tick = ao_sample_tick;
+
+ /* start logging data */
+ ao_log_start();
+
+#if HAS_RADIO
+ /* Increase telemetry rate */
+ ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_FLIGHT);
+
+ /* disable RDF beacon */
+ ao_rdf_set(0);
+#endif
+
+#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_boost_tick) > BOOST_TICKS_MAX)
+ {
+#if HAS_ACCEL
+ ao_flight_state = ao_flight_fast;
+ ao_coast_avg_accel = ao_accel;
+#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));
+ } else
+ goto check_re_boost;
+ break;
+#endif
+ case ao_flight_coast:
+
+ /*
+ * By customer request - allow the user
+ * to lock out apogee detection for a specified
+ * number of seconds.
+ */
+ if (ao_config.apogee_lockout) {
+ if ((ao_sample_tick - ao_boost_tick) <
+ AO_SEC_TO_TICKS(ao_config.apogee_lockout))
+ break;
+ }
+
+ /* 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
+ )
+ {
+#if HAS_IGNITE
+ /* ignite the drogue charge */
+ ao_ignite(ao_igniter_drogue);
+#endif
+
+#if HAS_RADIO
+ /* slow down the telemetry system */
+ ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_RECOVER);
+
+ /* Turn the RDF beacon back on */
+ ao_rdf_set(1);
+#endif
+
+ /* and enter drogue state */
+ ao_flight_state = ao_flight_drogue;
+ ao_wakeup(DATA_TO_XDATA(&ao_flight_state));
+ }
+#if HAS_ACCEL
+ else {
+ check_re_boost:
+ ao_coast_avg_accel = ao_coast_avg_accel - (ao_coast_avg_accel >> 6) + (ao_accel >> 6);
+ if (ao_coast_avg_accel > AO_MSS_TO_ACCEL(20)) {
+ ao_boost_tick = ao_sample_tick;
+ ao_flight_state = ao_flight_boost;
+ ao_wakeup(DATA_TO_XDATA(&ao_flight_state));
+ }
+ }
+#endif
+
+ 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)
+ {
+#if HAS_IGNITE
+ ao_ignite(ao_igniter_main);
+#endif
+
+ /*
+ * 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");
+}