X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=blobdiff_plain;f=ao_flight.c;h=51b2cd5eff138d8ff937f2fc3917ca4ca7aa0820;hp=48f7120260ef981b5c58c66fae449ab58334891d;hb=dcfcf3bec6788460b6fe8c239c80bad4526bd15b;hpb=fec4212a59a7b3321536b25707dcabc43c797c33

diff --git a/ao_flight.c b/ao_flight.c
index 48f71202..51b2cd5e 100644
--- a/ao_flight.c
+++ b/ao_flight.c
@@ -125,6 +125,8 @@ __pdata int16_t ao_raw_accel, ao_raw_accel_prev, ao_raw_pres;
  */
 __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
@@ -168,7 +170,7 @@ ao_flight(void)
 			 * 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 */
@@ -211,6 +213,8 @@ ao_flight(void)
 			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();
@@ -241,6 +245,16 @@ ao_flight(void)
 			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 AND velocity > 5m/s