X-Git-Url: https://git.gag.com/?a=blobdiff_plain;ds=sidebyside;f=ao_flight.c;h=37c138fe1586c1e1a6e32b4e2d3e8b826a09f79b;hb=70a69f3acdca27b80cdb2069de59bbc6dba83dbd;hp=ddf2d173c74e1839d9800622d48eb6c6e1d99292;hpb=b99315cee4ab796376458a2442cf36806fa4aed3;p=fw%2Faltos diff --git a/ao_flight.c b/ao_flight.c index ddf2d173..37c138fe 100644 --- a/ao_flight.c +++ b/ao_flight.c @@ -23,6 +23,7 @@ __pdata enum ao_flight_state ao_flight_state; /* current flight state */ __pdata uint16_t ao_flight_tick; /* time of last data */ +__pdata uint16_t ao_flight_prev_tick; /* time of previous data */ __pdata int16_t ao_flight_accel; /* filtered acceleration */ __pdata int16_t ao_flight_pres; /* filtered pressure */ __pdata int16_t ao_ground_pres; /* startup pressure */ @@ -69,11 +70,19 @@ __pdata int16_t ao_raw_accel, ao_raw_accel_prev, ao_raw_pres; * for all further flight computations */ +#define GRAVITY 9.80665 +/* convert m/s to velocity count */ +#define VEL_MPS_TO_COUNT(mps) ((int32_t) (((mps) / GRAVITY) * ACCEL_G * 100)) + #define ACCEL_G 265 #define ACCEL_ZERO_G 16000 -#define ACCEL_NOSE_UP (ACCEL_ZERO_G - ACCEL_G * 2 /3) +#define ACCEL_NOSE_UP (ACCEL_G * 2 /3) #define ACCEL_BOOST ACCEL_G * 2 -#define ACCEL_LAND (ACCEL_G / 10) +#define ACCEL_INT_LAND (ACCEL_G / 10) +#define ACCEL_VEL_LAND VEL_MPS_TO_COUNT(10) +#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) /* * Barometer calibration @@ -99,7 +108,8 @@ __pdata int16_t ao_raw_accel, ao_raw_accel_prev, ao_raw_pres; #define BARO_APOGEE (BARO_kPa / 10) /* .1kPa, or about 10m */ #define BARO_COAST (BARO_kPa * 5) /* 5kpa, or about 500m */ #define BARO_MAIN (BARO_kPa) /* 1kPa, or about 100m */ -#define BARO_LAND (BARO_kPa / 20) /* .05kPa, or about 5m */ +#define BARO_INT_LAND (BARO_kPa / 20) /* .05kPa, or about 5m */ +#define BARO_LAND (BARO_kPa * 10) /* 10kPa or about 1000m */ /* We also have a clock, which can be used to sanity check things in * case of other failures @@ -112,17 +122,16 @@ __pdata int16_t ao_raw_accel, ao_raw_accel_prev, ao_raw_pres; * velocity, and quite accurately too. As it gets updated 100 times a second, * it's scaled by 100 */ -__data int32_t ao_flight_vel; +__pdata int32_t ao_flight_vel; +__pdata int32_t ao_min_vel; __xdata int32_t ao_raw_accel_sum, ao_raw_pres_sum; -#define GRAVITY 9.80665 -/* convert m/s to velocity count */ -#define VEL_MPS_TO_COUNT(mps) ((int32_t) (((mps) / GRAVITY) * ACCEL_G * 100)) - /* 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 AO_INTERVAL_TICKS AO_SEC_TO_TICKS(20) + +#define abs(a) ((a) < 0 ? -(a) : (a)) void ao_flight(void) @@ -137,15 +146,36 @@ ao_flight(void) ao_interval_cur_max_pres = -0x7fff; ao_interval_cur_min_accel = 0x7fff; ao_interval_cur_max_accel = -0x7fff; + ao_flight_tick = 0; for (;;) { ao_sleep(&ao_adc_ring); while (ao_flight_adc != ao_adc_head) { + __pdata uint8_t ticks; + __pdata int16_t ao_vel_change; + ao_flight_prev_tick = ao_flight_tick; + + /* Capture a sample */ ao_raw_accel = ao_adc_ring[ao_flight_adc].accel; ao_raw_pres = ao_adc_ring[ao_flight_adc].pres; ao_flight_tick = ao_adc_ring[ao_flight_adc].tick; - /* all of our accelerations are negative, so subtract instead of add to get speed */ - ao_flight_vel -= (int32_t) (((ao_raw_accel + ao_raw_accel_prev) >> 1) - ao_ground_accel); + + /* Update velocity + * + * The accelerometer is mounted so that + * acceleration yields negative values + * while deceleration yields positive values, + * 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_raw_accel_prev = ao_raw_accel; + + /* one is a common interval */ + if (ticks == 1) + ao_flight_vel -= (int32_t) ao_vel_change; + else + ao_flight_vel -= (int32_t) ao_vel_change * (int32_t) ticks; + ao_flight_adc = ao_adc_ring_next(ao_flight_adc); } ao_flight_accel -= ao_flight_accel >> 4; @@ -155,6 +185,13 @@ ao_flight(void) if (ao_flight_pres < ao_min_pres) ao_min_pres = ao_flight_pres; + if (ao_flight_vel >= 0) { + if (ao_flight_vel < ao_min_vel) + ao_min_vel = ao_flight_vel; + } else { + if (-ao_flight_vel < ao_min_vel) + ao_min_vel = -ao_flight_vel; + } if (ao_flight_pres < ao_interval_cur_min_pres) ao_interval_cur_min_pres = ao_flight_pres; @@ -192,13 +229,27 @@ ao_flight(void) ao_ground_accel = (ao_raw_accel_sum / nsamples); ao_ground_pres = (ao_raw_pres_sum / nsamples); ao_min_pres = ao_ground_pres; - ao_main_pres = ao_ground_pres - BARO_MAIN; + ao_config_get(); + 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_interval_end = ao_flight_tick; /* Go to launchpad state if the nose is pointing up */ - if (ao_flight_accel < ACCEL_NOSE_UP) { + ao_config_get(); + if (ao_flight_accel < ao_config.accel_zero_g - ACCEL_NOSE_UP) { + + /* Disable the USB controller in flight mode + * to save power + */ + ao_usb_disable(); + + /* Turn on telemetry system + */ + ao_rdf_set(1); + ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_FLIGHT); + ao_flight_state = ao_flight_launchpad; ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } else { @@ -207,7 +258,6 @@ ao_flight(void) /* Turn on the Green LED in idle mode */ ao_led_on(AO_LED_GREEN); - ao_timer_set_adc_interval(100); ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } /* signal successful initialization by turning off the LED */ @@ -230,7 +280,13 @@ ao_flight(void) { ao_flight_state = ao_flight_boost; ao_launch_tick = ao_flight_tick; + + /* start logging data */ ao_log_start(); + + /* disable RDF beacon */ + ao_rdf_set(0); + ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); break; } @@ -254,32 +310,40 @@ ao_flight(void) ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); break; } - /* fall through ... */ + break; case ao_flight_coast: - /* boost/coast to apogee detect: + /* coast to apogee detect: * * accelerometer: integrated velocity < 200 m/s * OR * barometer: fall at least 500m from max altitude * * This extra state is required to avoid mis-detecting - * apogee due to mach transitions. For slow flights (<200m/s) - * we expect to transition right through this stage to - * apogee detect. + * apogee due to mach transitions. + * + * XXX this is essentially a single-detector test + * as the 500m altitude change would likely result + * in a loss of the rocket. More data on precisely + * how big a pressure change the mach transition + * generates would be useful here. */ - if (ao_flight_vel < VEL_MPS_TO_COUNT(200) || + if (ao_flight_vel < ACCEL_VEL_MACH || ao_flight_pres > ao_min_pres + BARO_COAST) { + /* set min velocity to current velocity for + * apogee detect + */ + ao_min_vel = ao_flight_vel; ao_flight_state = ao_flight_apogee; ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } break; case ao_flight_apogee: - /* apogee to drogue deploy: + /* apogee detect to drogue deploy: * - * accelerometer: integrated velocity < 10m/s + * accelerometer: abs(velocity) > min_velocity + 2m/s * OR * barometer: fall at least 10m * @@ -290,10 +354,21 @@ ao_flight(void) * over in that case and the integrated velocity * measurement should suffice to find apogee */ - if (ao_flight_vel < VEL_MPS_TO_COUNT(-10) || - ao_flight_pres - BARO_APOGEE > ao_min_pres) + if (abs(ao_flight_vel) > ao_min_vel + ACCEL_VEL_APOGEE || + ao_flight_pres > ao_min_pres + BARO_APOGEE) { + /* ignite the drogue charge */ ao_ignite(ao_igniter_drogue); + + /* slow down the telemetry system */ + ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_RECOVER); + + /* slow down the ADC sample rate */ + ao_timer_set_adc_interval(10); + + /* Enable RDF beacon */ + ao_rdf_set(1); + ao_flight_state = ao_flight_drogue; ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } @@ -302,12 +377,12 @@ ao_flight(void) /* drogue to main deploy: * - * accelerometer: abs(velocity) > 50m/s + * accelerometer: abs(velocity) > 100m/s (in case the drogue failed) * OR * barometer: reach main deploy altitude */ - if (ao_flight_vel < VEL_MPS_TO_COUNT(-50) || - ao_flight_vel > VEL_MPS_TO_COUNT(50) || + if (ao_flight_vel < -ACCEL_VEL_MAIN || + ao_flight_vel > ACCEL_VEL_MAIN || ao_flight_pres >= ao_main_pres) { ao_ignite(ao_igniter_main); @@ -319,26 +394,50 @@ ao_flight(void) /* drogue/main to land: * - * accelerometer: value stable - * AND - * barometer: altitude stable + * accelerometer: value stable and velocity less than 10m/s + * OR + * barometer: altitude stable and within 1000m of the launch altitude */ - if ((ao_interval_max_accel - ao_interval_min_accel) < ACCEL_LAND && - (ao_interval_max_pres - ao_interval_min_pres) < BARO_LAND) + if ((abs(ao_flight_vel) < ACCEL_VEL_LAND && + (ao_interval_max_accel - ao_interval_min_accel) < ACCEL_INT_LAND) || + (ao_flight_pres > ao_ground_pres - BARO_LAND && + (ao_interval_max_pres - ao_interval_min_pres) < BARO_INT_LAND)) { 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)); } break; case ao_flight_landed: - ao_log_stop(); break; } } } +#define AO_ACCEL_COUNT_TO_MSS(count) ((count) / 27) +#define AO_VEL_COUNT_TO_MS(count) ((int16_t) ((count) / 2700)) + +static void +ao_flight_status(void) +{ + printf("STATE: %7s accel: %d speed: %d altitude: %d main: %d\n", + ao_state_names[ao_flight_state], + AO_ACCEL_COUNT_TO_MSS(ACCEL_ZERO_G - ao_flight_accel), + AO_VEL_COUNT_TO_MS(ao_flight_vel), + ao_pres_to_altitude(ao_flight_pres), + ao_pres_to_altitude(ao_main_pres)); +} + static __xdata struct ao_task flight_task; +__code struct ao_cmds ao_flight_cmds[] = { + { 'f', ao_flight_status, "f Display current flight state" }, + { 0, ao_flight_status, NULL } +}; + void ao_flight_init(void) { @@ -350,5 +449,5 @@ ao_flight_init(void) ao_interval_end = AO_INTERVAL_TICKS; ao_add_task(&flight_task, ao_flight, "flight"); + ao_cmd_register(&ao_flight_cmds[0]); } -