X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=blobdiff_plain;f=src%2Fao_flight.c;h=c6cbbf7cbaeb3e26f64bf6069e427fe864f4a561;hp=81aecad3e26e0053059b65a90b7273a9504d627a;hb=66bdf0e066bc0bb7a326a6c2a9c88b69e5c1be66;hpb=da42f406e88ccc821cd45d5a94d5afec65ec50e9 diff --git a/src/ao_flight.c b/src/ao_flight.c index 81aecad3..c6cbbf7c 100644 --- a/src/ao_flight.c +++ b/src/ao_flight.c @@ -19,97 +19,32 @@ #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_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 */ -__pdata int16_t ao_ground_accel; /* startup acceleration */ -__pdata int16_t ao_min_pres; /* minimum recorded pressure */ __pdata uint16_t ao_launch_tick; /* time of launch detect */ -__pdata int16_t ao_main_pres; /* pressure to eject main */ /* * track min/max data over a long interval to detect * resting */ __pdata uint16_t ao_interval_end; -__pdata int16_t ao_interval_cur_min_accel; -__pdata int16_t ao_interval_cur_max_accel; -__pdata int16_t ao_interval_cur_min_pres; -__pdata int16_t ao_interval_cur_max_pres; -__pdata int16_t ao_interval_min_accel; -__pdata int16_t ao_interval_max_accel; -__pdata int16_t ao_interval_min_pres; -__pdata int16_t ao_interval_max_pres; - -__data uint8_t ao_flight_adc; -__pdata int16_t ao_raw_accel, ao_raw_accel_prev, ao_raw_pres; -__pdata int16_t ao_accel_2g; - -__xdata uint8_t ao_flight_force_idle; - -/* Accelerometer calibration - * - * We're sampling the accelerometer through a resistor divider which - * consists of 5k and 10k resistors. This multiplies the values by 2/3. - * That goes into the cc1111 A/D converter, which is running at 11 bits - * of precision with the bits in the MSB of the 16 bit value. Only positive - * values are used, so values should range from 0-32752 for 0-3.3V. The - * specs say we should see 40mV/g (uncalibrated), multiply by 2/3 for what - * the A/D converter sees (26.67 mV/g). We should see 32752/3300 counts/mV, - * for a final computation of: - * - * 26.67 mV/g * 32767/3300 counts/mV = 264.8 counts/g - * - * Zero g was measured at 16000 (we would expect 16384). - * Note that this value is only require to tell if the - * rocket is standing upright. Once that is determined, - * the value of the accelerometer is averaged for 100 samples - * to find the resting accelerometer value, which is used - * 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) * (AO_HERTZ/2))) * (int32_t) ao_accel_2g) - -#define ACCEL_NOSE_UP (ao_accel_2g >> 2) -#define ACCEL_BOOST ao_accel_2g -#define ACCEL_COAST (ao_accel_2g >> 3) -#define ACCEL_INT_LAND (ao_accel_2g >> 3) -#define ACCEL_VEL_MACH VEL_MPS_TO_COUNT(200) -#define ACCEL_VEL_BOOST VEL_MPS_TO_COUNT(5) +__pdata int16_t ao_interval_min_height; +__pdata int16_t ao_interval_max_height; -/* - * Barometer calibration - * - * We directly sample the barometer. The specs say: - * - * Pressure range: 15-115 kPa - * Voltage at 115kPa: 2.82 - * Output scale: 27mV/kPa - * - * If we want to detect launch with the barometer, we need - * a large enough bump to not be fooled by noise. At typical - * launch elevations (0-2000m), a 200Pa pressure change cooresponds - * to about a 20m elevation change. This is 5.4mV, or about 3LSB. - * As all of our calculations are done in 16 bits, we'll actually see a change - * of 16 times this though - * - * 27 mV/kPa * 32767 / 3300 counts/mV = 268.1 counts/kPa - */ - -#define BARO_kPa 268 -#define BARO_LAUNCH (BARO_kPa / 5) /* .2kPa, or about 20m */ -#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_INT_LAND (BARO_kPa / 20) /* .05kPa, or about 5m */ -#define BARO_LAND (BARO_kPa * 10) /* 10kPa or about 1000m */ +__xdata uint8_t ao_flight_force_idle; /* We also have a clock, which can be used to sanity check things in * case of other failures @@ -117,17 +52,6 @@ __xdata uint8_t ao_flight_force_idle; #define BOOST_TICKS_MAX AO_SEC_TO_TICKS(15) -/* This value is scaled in a weird way. It's a running total of accelerometer - * readings minus the ground accelerometer reading. That means it measures - * velocity, and quite accurately too. As it gets updated 100 times a second, - * it's scaled by 100 - */ -__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 * for a fairly long time (AO_INTERVAL_TICKS) */ @@ -138,201 +62,55 @@ __xdata int32_t ao_raw_accel_sum, ao_raw_pres_sum; void ao_flight(void) { - __pdata static uint16_t nsamples = 0; - - ao_flight_adc = ao_adc_head; - ao_raw_accel_prev = 0; - ao_raw_accel = 0; - ao_raw_pres = 0; - ao_flight_tick = 0; + ao_sample_init(); + ao_flight_state = ao_flight_startup; for (;;) { - ao_wakeup(DATA_TO_XDATA(&ao_flight_adc)); - ao_sleep(DATA_TO_XDATA(&ao_adc_head)); - while (ao_flight_adc != ao_adc_head) { - __pdata uint8_t ticks; - __pdata int16_t ao_vel_change; - __xdata struct ao_adc *ao_adc; - ao_flight_prev_tick = ao_flight_tick; - - /* Capture a sample */ - ao_adc = &ao_adc_ring[ao_flight_adc]; - ao_flight_tick = ao_adc->tick; - ao_raw_accel = ao_adc->accel; -#if HAS_ACCEL_REF - /* - * Ok, the math here is a bit tricky. - * - * ao_raw_accel: ADC output for acceleration - * ao_accel_ref: ADC output for the 5V reference. - * ao_cook_accel: Corrected acceleration value - * Vcc: 3.3V supply to the CC1111 - * Vac: 5V supply to the accelerometer - * accel: input voltage to accelerometer ADC pin - * ref: input voltage to 5V reference ADC pin - * - * - * Measured acceleration is ratiometric to Vcc: - * - * ao_raw_accel accel - * ------------ = ----- - * 32767 Vcc - * - * Measured 5v reference is also ratiometric to Vcc: - * - * ao_accel_ref ref - * ------------ = ----- - * 32767 Vcc - * - * - * ao_accel_ref = 32767 * (ref / Vcc) - * - * Acceleration is measured ratiometric to the 5V supply, - * so what we want is: - * - * ao_cook_accel accel - * ------------- = ----- - * 32767 ref - * - * - * accel Vcc - * = ----- * --- - * Vcc ref - * - * ao_raw_accel 32767 - * = ------------ * ------------ - * 32737 ao_accel_ref - * - * Multiply through by 32767: - * - * ao_raw_accel * 32767 - * ao_cook_accel = -------------------- - * ao_accel_ref - * - * Now, the tricky part. Getting this to compile efficiently - * and keeping all of the values in-range. - * - * First off, we need to use a shift of 16 instead of * 32767 as SDCC - * does the obvious optimizations for byte-granularity shifts: - * - * ao_cook_accel = (ao_raw_accel << 16) / ao_accel_ref - * - * Next, lets check our input ranges: - * - * 0 <= ao_raw_accel <= 0x7fff (singled ended ADC conversion) - * 0x7000 <= ao_accel_ref <= 0x7fff (the 5V ref value is close to 0x7fff) - * - * Plugging in our input ranges, we get an output range of 0 - 0x12490, - * which is 17 bits. That won't work. If we take the accel ref and shift - * by a bit, we'll change its range: - * - * 0xe000 <= ao_accel_ref<<1 <= 0xfffe - * - * ao_cook_accel = (ao_raw_accel << 16) / (ao_accel_ref << 1) - * - * Now the output range is 0 - 0x9248, which nicely fits in 16 bits. It - * is, however, one bit too large for our signed computations. So, we - * take the result and shift that by a bit: - * - * ao_cook_accel = ((ao_raw_accel << 16) / (ao_accel_ref << 1)) >> 1 - * - * This finally creates an output range of 0 - 0x4924. As the ADC only - * provides 11 bits of data, we haven't actually lost any precision, - * just dropped a bit of noise off the low end. - */ - ao_raw_accel = (uint16_t) ((((uint32_t) ao_raw_accel << 16) / (ao_accel_ref[ao_flight_adc] << 1))) >> 1; - ao_adc->accel = ao_raw_accel; -#endif - ao_raw_pres = ao_adc->pres; - - 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 - * 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_ground_accel - (((ao_raw_accel + 1) >> 1) + ((ao_raw_accel_prev + 1) >> 1)); - 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); - } - - 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; - } + /* + * Process ADC samples, just looping + * until the sensors are calibrated. + */ + if (!ao_sample()) + continue; switch (ao_flight_state) { case ao_flight_startup: - /* startup state: - * - * Collect 512 samples of acceleration and pressure - * data and average them to find the resting values - */ - if (nsamples < 512) { - ao_raw_accel_sum += ao_raw_accel; - ao_raw_pres_sum += ao_raw_pres; - ++nsamples; - continue; - } - ao_ground_accel = ao_raw_accel_sum >> 9; - ao_ground_pres = ao_raw_pres_sum >> 9; - ao_min_pres = ao_ground_pres; - ao_config_get(); - ao_main_pres = ao_altitude_to_pres(ao_pres_to_altitude(ao_ground_pres) + ao_config.main_deploy); - ao_accel_2g = ao_config.accel_minus_g - ao_config.accel_plus_g; - ao_flight_vel = 0; - ao_min_vel = 0; - ao_old_vel = ao_flight_vel; - ao_old_vel_tick = ao_flight_tick; - /* 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 */ - ao_config_get(); +#if HAS_ACCEL if (ao_config.accel_plus_g == 0 || ao_config.accel_minus_g == 0 || - ao_flight_accel < ao_config.accel_plus_g - ACCEL_NOSE_UP || - ao_flight_accel > ao_config.accel_minus_g + ACCEL_NOSE_UP) + 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; - /* Allow packet mode in invalid flight state, - * Still need to be able to fix the problem! - */ - ao_packet_slave_start(); - } else if (ao_flight_accel < ao_config.accel_plus_g + ACCEL_NOSE_UP && - !ao_flight_force_idle) + } 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); @@ -344,9 +122,6 @@ ao_flight(void) /* Set idle mode */ ao_flight_state = ao_flight_idle; - /* Turn on packet system in idle mode */ - ao_packet_slave_start(); - /* signal successful initialization by turning off the LED */ ao_led_off(AO_LED_RED); } @@ -356,32 +131,28 @@ ao_flight(void) break; case ao_flight_pad: - /* 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 AND velocity > 5m/s - * OR * 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 + * 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_flight_accel < ao_ground_accel - ACCEL_BOOST && - ao_flight_vel > ACCEL_VEL_BOOST) || - ao_flight_pres < ao_ground_pres - BARO_LAUNCH) + 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_flight_tick; + ao_launch_tick = ao_sample_tick; /* start logging data */ ao_log_start(); @@ -392,9 +163,11 @@ ao_flight(void) /* 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; @@ -412,55 +185,48 @@ ao_flight(void) * deceleration, or by waiting until the maximum burn duration * (15 seconds) has past. */ - if (ao_flight_accel > ao_ground_accel + ACCEL_COAST || - (int16_t) (ao_flight_tick - ao_launch_tick) > BOOST_TICKS_MAX) + 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; } break; +#if HAS_ACCEL case ao_flight_fast: - - /* fast to coast: - * - * 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. - * - * 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. + /* + * This is essentially the same as coast, + * but the barometer is being ignored as + * it may be unreliable. */ - if (ao_flight_vel < ACCEL_VEL_MACH || - ao_flight_pres > ao_min_pres + BARO_COAST) + if (ao_speed < AO_MS_TO_SPEED(AO_MAX_BARO_SPEED)) { - /* set min velocity to current velocity for - * apogee detect - */ - ao_min_vel = abs(ao_flight_vel); ao_flight_state = ao_flight_coast; ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); + break; } break; +#endif case ao_flight_coast: /* apogee detect: coast to drogue deploy: * - * barometer: fall at least 10m + * speed: < 0 * - * It would be nice to use the accelerometer - * to detect apogee as well, but tests have - * shown that flights far from vertical would - * grossly mis-detect apogee. So, for now, - * we'll trust to a single sensor for this test + * Also make sure the model altitude is tracking + * the measured altitude reasonably closely; otherwise + * we're probably transsonic. */ - if (ao_flight_pres > ao_min_pres + BARO_APOGEE) + 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); @@ -468,26 +234,18 @@ ao_flight(void) /* 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); + /* Turn the RDF beacon back on */ + ao_rdf_set(1); /* - * Start recording min/max accel and pres for a while + * Start recording min/max height * 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_end = ao_sample_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; + ao_interval_min_height = ao_interval_max_height = ao_height; /* and enter drogue state */ ao_flight_state = ao_flight_drogue; @@ -509,7 +267,7 @@ ao_flight(void) * at that point. Perhaps also use the drogue sense lines * to notice continutity? */ - if (ao_flight_pres >= ao_main_pres) + if (ao_height <= ao_config.main_deploy) { ao_ignite(ao_igniter_main); ao_flight_state = ao_flight_main; @@ -521,42 +279,27 @@ ao_flight(void) /* drogue/main to land: * - * accelerometer: value stable - * AND * barometer: altitude stable and within 1000m of the launch altitude */ - if (ao_flight_pres < ao_interval_cur_min_pres) - ao_interval_cur_min_pres = ao_flight_pres; - if (ao_flight_pres > ao_interval_cur_max_pres) - ao_interval_cur_max_pres = ao_flight_pres; - if (ao_flight_accel < ao_interval_cur_min_accel) - ao_interval_cur_min_accel = ao_flight_accel; - if (ao_flight_accel > ao_interval_cur_max_accel) - ao_interval_cur_max_accel = ao_flight_accel; - - if ((int16_t) (ao_flight_tick - ao_interval_end) >= 0) { - ao_interval_max_pres = ao_interval_cur_max_pres; - ao_interval_min_pres = ao_interval_cur_min_pres; - ao_interval_max_accel = ao_interval_cur_max_accel; - ao_interval_min_accel = ao_interval_cur_min_accel; - 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; - - 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) + if (ao_height < ao_interval_min_height) + ao_interval_min_height = ao_height; + if (ao_height > ao_interval_max_height) + ao_interval_max_height = ao_height; + + if ((int16_t) (ao_sample_tick - ao_interval_end) >= 0) { + if (ao_height < AO_M_TO_HEIGHT(1000) && + ao_interval_max_height - ao_interval_min_height < AO_M_TO_HEIGHT(5)) { ao_flight_state = ao_flight_landed; /* turn off the ADC capture */ ao_timer_set_adc_interval(0); - /* Enable RDF beacon */ - ao_rdf_set(1); ao_wakeup(DATA_TO_XDATA(&ao_flight_state)); } + ao_interval_min_height = ao_interval_max_height = ao_height; + ao_interval_end = ao_sample_tick + AO_INTERVAL_TICKS; } break; case ao_flight_landed: