#define ACCEL_VEL_MACH VEL_MPS_TO_COUNT(200)
#define ACCEL_VEL_APOGEE VEL_MPS_TO_COUNT(2)
#define ACCEL_VEL_MAIN VEL_MPS_TO_COUNT(100)
+#define ACCEL_VEL_BOOST VEL_MPS_TO_COUNT(5)
/*
* Barometer calibration
*/
__pdata int32_t ao_flight_vel;
__pdata int32_t ao_min_vel;
+__pdata int32_t ao_old_vel;
+__pdata int16_t ao_old_vel_tick;
__xdata int32_t ao_raw_accel_sum, ao_raw_pres_sum;
/* Landing is detected by getting constant readings from both pressure and accelerometer
ao_raw_pres = ao_adc_ring[ao_flight_adc].pres;
ao_flight_tick = ao_adc_ring[ao_flight_adc].tick;
+ ao_flight_accel -= ao_flight_accel >> 4;
+ ao_flight_accel += ao_raw_accel >> 4;
+ ao_flight_pres -= ao_flight_pres >> 4;
+ ao_flight_pres += ao_raw_pres >> 4;
/* Update velocity
*
* The accelerometer is mounted so that
* so subtract instead of add.
*/
ticks = ao_flight_tick - ao_flight_prev_tick;
- ao_vel_change = (((ao_raw_accel + ao_raw_accel_prev) >> 1) - ao_ground_accel);
+ ao_vel_change = (((ao_raw_accel >> 1) + (ao_raw_accel_prev >> 1)) - ao_ground_accel);
ao_raw_accel_prev = ao_raw_accel;
/* one is a common interval */
ao_flight_adc = ao_adc_ring_next(ao_flight_adc);
}
- ao_flight_accel -= ao_flight_accel >> 4;
- ao_flight_accel += ao_raw_accel >> 4;
- ao_flight_pres -= ao_flight_pres >> 4;
- ao_flight_pres += ao_raw_pres >> 4;
if (ao_flight_pres < ao_min_pres)
ao_min_pres = ao_flight_pres;
ao_main_pres = ao_altitude_to_pres(ao_pres_to_altitude(ao_ground_pres) + ao_config.main_deploy);
ao_flight_vel = 0;
ao_min_vel = 0;
+ ao_old_vel = ao_flight_vel;
+ ao_old_vel_tick = ao_flight_tick;
/* Go to launchpad state if the nose is pointing up */
ao_config_get();
/* Turn on telemetry system
*/
- ao_rdf_set(1);
- ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_FLIGHT);
+ ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_PAD);
ao_flight_state = ao_flight_launchpad;
ao_wakeup(DATA_TO_XDATA(&ao_flight_state));
break;
case ao_flight_launchpad:
+ /* Trim velocity
+ *
+ * Once a second, remove any velocity from
+ * a second ago
+ */
+ if ((int16_t) (ao_flight_tick - ao_old_vel_tick) >= AO_SEC_TO_TICKS(1)) {
+ ao_old_vel_tick = ao_flight_tick;
+ ao_flight_vel -= ao_old_vel;
+ ao_old_vel = ao_flight_vel;
+ }
/* pad to boost:
*
- * accelerometer: > 2g
+ * accelerometer: > 2g AND velocity > 5m/s
* OR
* barometer: > 20m vertical motion
*
* the barometer, but we use both to make sure this
* transition is detected
*/
- if (ao_flight_accel < ao_ground_accel - ACCEL_BOOST ||
+ if ((ao_flight_accel < ao_ground_accel - ACCEL_BOOST &&
+ ao_flight_vel > ACCEL_VEL_BOOST) ||
ao_flight_pres < ao_ground_pres - BARO_LAUNCH)
{
ao_flight_state = ao_flight_boost;
/* start logging data */
ao_log_start();
- /* disable RDF beacon */
- ao_rdf_set(0);
+ /* Increase telemetry rate */
+ ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_FLIGHT);
ao_wakeup(DATA_TO_XDATA(&ao_flight_state));
break;
/* set min velocity to current velocity for
* apogee detect
*/
- ao_min_vel = ao_flight_vel;
+ ao_min_vel = abs(ao_flight_vel);
ao_flight_state = ao_flight_apogee;
ao_wakeup(DATA_TO_XDATA(&ao_flight_state));
}
* over in that case and the integrated velocity
* measurement should suffice to find apogee
*/
- if (abs(ao_flight_vel) > ao_min_vel + ACCEL_VEL_APOGEE ||
+ if (/* abs(ao_flight_vel) > ao_min_vel + ACCEL_VEL_APOGEE || */
ao_flight_pres > ao_min_pres + BARO_APOGEE)
{
/* ignite the drogue charge */
/* slow down the ADC sample rate */
ao_timer_set_adc_interval(10);
- /* Enable RDF beacon */
- ao_rdf_set(1);
+ /*
+ * Start recording min/max accel and pres for a while
+ * to figure out when the rocket has landed
+ */
+ /* Set the 'last' limits to max range to prevent
+ * early resting detection
+ */
+ ao_interval_min_accel = 0;
+ ao_interval_max_accel = 0x7fff;
+ ao_interval_min_pres = 0;
+ ao_interval_max_pres = 0x7fff;
+
+ /* initialize interval values */
+ ao_interval_end = ao_flight_tick + AO_INTERVAL_TICKS;
+
+ ao_interval_cur_min_pres = ao_interval_cur_max_pres = ao_flight_pres;
+ ao_interval_cur_min_accel = ao_interval_cur_max_accel = ao_flight_accel;
+ /* and enter drogue state */
ao_flight_state = ao_flight_drogue;
ao_wakeup(DATA_TO_XDATA(&ao_flight_state));
}
- /*
- * Start recording min/max accel and pres for a while
- * to figure out when the rocket has landed
- */
- /* Set the 'last' limits to max range to prevent
- * early resting detection
- */
- ao_interval_min_accel = 0;
- ao_interval_max_accel = 0x7fff;
- ao_interval_min_pres = 0;
- ao_interval_max_pres = 0x7fff;
-
- /* initialize interval values */
- ao_interval_end = ao_flight_tick + AO_INTERVAL_TICKS;
-
- ao_interval_cur_min_pres = ao_interval_cur_max_pres = ao_flight_pres;
- ao_interval_cur_min_accel = ao_interval_cur_max_accel = ao_flight_accel;
break;
case ao_flight_drogue:
/* drogue to main deploy:
*
- * accelerometer: abs(velocity) > 100m/s (in case the drogue failed)
- * OR
* 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_flight_vel < -ACCEL_VEL_MAIN ||
- ao_flight_vel > ACCEL_VEL_MAIN ||
- ao_flight_pres >= ao_main_pres)
+ if (ao_flight_pres >= ao_main_pres)
{
ao_ignite(ao_igniter_main);
ao_flight_state = ao_flight_main;
/* drogue/main to land:
*
- * accelerometer: value stable and velocity less than 10m/s
- * OR
+ * accelerometer: value stable
+ * AND
* barometer: altitude stable and within 1000m of the launch altitude
*/
ao_interval_cur_min_accel = ao_interval_cur_max_accel = ao_flight_accel;
}
- if ((abs(ao_flight_vel) < ACCEL_VEL_LAND &&
- (uint16_t) (ao_interval_max_accel - ao_interval_min_accel) < (uint16_t) ACCEL_INT_LAND) ||
- (ao_flight_pres > ao_ground_pres - BARO_LAND &&
- (uint16_t) (ao_interval_max_pres - ao_interval_min_pres) < (uint16_t) BARO_INT_LAND))
+ if ((uint16_t) (ao_interval_max_accel - ao_interval_min_accel) < (uint16_t) ACCEL_INT_LAND &&
+ ao_flight_pres > ao_ground_pres - BARO_LAND &&
+ (uint16_t) (ao_interval_max_pres - ao_interval_min_pres) < (uint16_t) BARO_INT_LAND)
{
ao_flight_state = ao_flight_landed;