Commit Graph

528 Commits

Author SHA1 Message Date
Paul Riseborough cb59570938 AP_NavEKF: Remove bug preventing external selection of optical flow mode 2015-05-09 18:31:18 +10:00
Tom Pittenger 2deb0e08ea AP_NavEKF: replace fabs() with fabsf() 2015-05-09 09:57:27 +10:00
Paul Riseborough a232606fc9 AP_NavEKF: Prevent EKF yaw errors due to fast yaw spins
Prolonged yaw rotations with gyro scale factor errors can cause yaw errors and gyro bias estimation errors to build up to a point where EKF health checks fail.
This patch introduces the following protections:

1) The assumed yaw gyro error is scaled using a filtered yaw rate and an assumed 3% scale factor error (MPU6000 data sheet)
2) When the filtered yaw rate magnitude is greater than 1 rad/sec, the Z gyro bias process noise is zeroed and the state variance set to zero to inhibit modification of the bias state
3) When the filtered yaw rate magnitude is greater than 1 rad/sec, the magnetometer quaternion corrections are scaled by a factor of four to maintain tighter alignment with the compass
2015-05-08 16:47:31 +09:00
Paul Riseborough 08382373f1 AP_NavEKF: Reduce likelihood of in-air switch to GPS with a bad heading
Increases magnetometer weighting on yaw corrections when there there is no other aiding to constrain yaw drift.
Prevents switch to GPS if magnetometer data is failing innovation checks which indicates a bad yaw angle
2015-05-08 16:47:29 +09:00
Jonathan Challinger 142e018a18 AP_NavEKF: fix bug causing takeoff to fail 2015-05-08 09:15:45 +09:00
Andrew Tridgell a140a5e77f AP_NavEKF: revert AP_Math class change 2015-05-05 13:27:07 +10:00
Tom Pittenger 9b53961a7d AP_NavEKF: compiler warnings: float to double 2015-05-05 13:26:52 +10:00
Tom Pittenger 3276eec30e AP_NavEKF: compiler warnings: apply is_zero(float) or is_equal(float) 2015-05-05 13:26:52 +10:00
Andrew Tridgell c4d6f9d040 AP_NavEKF: fix for HAL_SITL rename 2015-05-05 09:45:55 +10:00
Andrew Tridgell ce0a863d01 AP_NavEKF: allow for optimisation of the EKF
disable optimisation when debugging needed
2015-05-05 09:45:53 +10:00
Paul Riseborough be04be9b43 AP_NavEKF: Fix bug preventing home position being set by copter
The interface definition has been modified so that it returns true for a position obtained usin geither the normal inertial navigation calculation, or a raw GPS measurement.
This enables this function to be used to set a home position before flight.
2015-05-02 17:20:21 +09:00
Randy Mackay fb7e75594f AP_NavEKF: replace memset with quaternion.initialise 2015-05-01 16:37:35 +09:00
Randy Mackay c366fbbc96 AP_NavEKF: remove unused haveDeltaAngles 2015-05-01 16:37:33 +09:00
Paul Riseborough b71b8f4bda AP_NavEKF: Always return a NED relative position if possible
If a calculated position is not available, the function will return a value based on raw GPS or last calculation if available, but the status will be set to false to indicate that it cannot be used for control.
2015-05-01 16:37:32 +09:00
Paul Riseborough 20ba1e6b1b AP_NavEKF: Always return a WGS-84 location if possible
If a calculated location is not available, the function will return raw GPS data if available, but the status will be set to false.
2015-05-01 16:37:31 +09:00
Paul Riseborough dd1e0b2f0b AP_NavEKF: Add missing function to return the NED to XYZ quaternion 2015-05-01 16:37:30 +09:00
Paul Riseborough 2c4572eb50 AP_NavEKF: Make ground effect variable names more descriptive 2015-05-01 16:37:29 +09:00
Paul Riseborough 3986851c51 AP_NavEKF: Prevent Z accel bias changing during ground effect takeoff
The inconsistent baro data during ground effect takeoff combined with the larger variances in the Z accel bias state early in flight can cause unwanted changes in bias estimate and therefore changes in height estimation error.
This patch turns of the process noise and state updates for the Z accel bias state when takeoff in ground effect is expected.
2015-05-01 16:37:28 +09:00
Paul Riseborough 2cba60c731 AP_NavEKF: Decouple takeoff ground effect compensation from arm transtion
Thsi fixes a potential bug where the vehicle could land at a lower location without disarming and re-enter ground effect takeoff mode wiht a baro height floor above the current altitude, causing unpredictable height gain
2015-05-01 16:37:27 +09:00
Paul Riseborough c4c0f819b5 AP_NavEKF: Ensure Covariance initialisation uses correct IMU time step 2015-05-01 16:37:26 +09:00
Paul Riseborough 5dc29699ab AP_NavEKF: Publish the INS delta quaternion 2015-05-01 16:37:25 +09:00
Paul Riseborough d273302ce7 AP_NavEKF: Improve rate of accel bias learning before flight 2015-05-01 16:37:24 +09:00
Paul Riseborough 8dc6354a54 AP_NavEKF: Prevent touchdown baro errors tripping height innovation check
Ground effect baro errors can cause a spike in height innovation on disarming if ground effect compensation was used during the landing. This causes a transient AHRS fault message if this innovation is outside the pre-arm check limits.
Resetting the vertical position state to the measured height after disarming prevents this.
2015-05-01 16:37:23 +09:00
Jonathan Challinger 2f38dd1b67 AP_NavEKF: use quaternion functions to apply IMU delta angles 2015-05-01 16:37:22 +09:00
Jonathan Challinger 9c374eb4a8 AP_NavEKF: apply constrained floor to barometer innovation while landing 2015-05-01 16:37:21 +09:00
Jonathan Challinger 3c6446fadd AP_NavEKF: refactor meaHgtAtTakeOff filter 2015-05-01 16:37:20 +09:00
Paul Riseborough 744de74c16 AP_NavEKF: Reduce ground effect baro induced height errors during takeoff 2015-05-01 16:37:19 +09:00
Paul Riseborough 13616d6436 AP_NavEKF: Add takeoff and touchdown expected to reported filter status 2015-05-01 16:37:19 +09:00
Jonathan Challinger 8c92524b8a AP_NavEKF: add takeoffExpected and touchdownExpected 2015-05-01 16:37:18 +09:00
Jonathan Challinger b6b55bf6f2 AP_NavEKF: integrate gravity over correct time period 2015-05-01 16:37:17 +09:00
Jonathan Challinger cb0c424da1 AP_NavEKF: rewrite readIMUData 2015-05-01 16:37:16 +09:00
Andrew Tridgell 514c349060 AP_NavEKF: raise DCM error_rp threshold to 0.05
it was failing on many boards with fixed wing
2015-04-28 14:07:39 +10:00
Randy Mackay fdf226ebc1 AP_NavEKF: include AP_RangeFinder.h 2015-04-24 15:49:11 +09:00
Tom Pittenger a340d13d01 NavEKF: fix compile warning re member init order 2015-04-24 14:14:12 +09:00
Tom Pittenger d6b34209b5 NavEKF: fix compile warnings re float constants 2015-04-24 14:04:02 +09:00
Randy Mackay b05bdd657d AP_NavEKF: getHeightControlLimit modifies height on success 2015-04-24 10:58:05 +09:00
Paul Riseborough cf04600710 AP_NavEKF: Add public function to limit height control during OF nav 2015-04-24 10:57:56 +09:00
Paul Riseborough 68b225de4d AP_NavEKF: Prevent pre-arm baro drift affecting mag field reset height 2015-04-24 10:57:54 +09:00
Paul Riseborough c2e6fdb56c AP_NavEKF: Reduce effect of noisy baro data on baro height offset estimate
This estimate is used to offset baro data if we need to switch across from range finder data due to sensor failure. The previous filter coefficients gave a 0.5 seconds time constant on the offset which was too susceptible to baro noise.
2015-04-24 10:57:51 +09:00
Paul Riseborough fd7fdc1ad9 AP_NavEKF: Remove unnecessary state resets on arm and disarm
Resetting states unnecessarily creates transients due to presence of bias errors
2015-04-24 10:57:49 +09:00
Paul Riseborough 3e67080002 AP_NavEKF: Use GPS vertical velocity observations to estimate Z accel bias 2015-04-24 10:57:47 +09:00
Paul Riseborough e48171ab11 AP_NavEKF: Improve takeoff with optical flow and range data loss
Range finder and optical flow data can drop-out and be reliable very close to ground. these patches enable the takeoff to be more relaibly detected and constrain optical flow navigation drift in the first part of takeoff.
2015-04-24 10:57:45 +09:00
Paul Riseborough 3e061b174e AP_NavEKF: Report unhealthy for all filter faults 2015-04-24 10:57:43 +09:00
Paul Riseborough 6c4c54c2ba AP_NavEKF: Use default on ground range parameter from range finder object 2015-04-24 10:57:41 +09:00
Jonathan Challinger 10476333d8 AP_NavEKF: don't run when previously disarmed and time has slipped 2015-04-24 10:57:39 +09:00
Jonathan Challinger 085faaac6a AP_NavEKF: fix delay detection so that filter properly resets after a delay 2015-04-24 10:57:36 +09:00
Paul Riseborough 1c8e3f9444 AP_NavEKF: Allow EKF to pull data from range finder object 2015-04-24 10:57:01 +09:00
Paul Riseborough 4a5bf0a266 AP_NavEKF: Reduce EKF start time
Makes EKF start conditional on DCM solution tilt error
2015-04-23 20:35:48 +09:00
Arthur Benemann e59c6ddbae AP_SmallEKF: increase start-up time of the SmallEKF 2015-04-21 21:45:51 +09:00
Arthur Benemann 4ad3e786a5 AP_NavEKF: fix initialization of the SmallEKF
The constructor 'states' variable was not being called. To make sure other variables where also zeroed now
2015-04-21 21:45:36 +09:00