Commit Graph

178 Commits

Author SHA1 Message Date
priseborough 114bd56e2a AP_NavEKF: Fix display names in parameter list 2014-04-30 06:35:41 +10:00
priseborough 5fefce5899 AP_NavEKF: Synthetic sideslip fusion numerical error protections 2014-04-29 17:26:45 +10:00
priseborough ecc8e45eda AP_NavEKF: Fix bug in position reset logic 2014-04-23 18:16:02 +10:00
Andrew Tridgell 25667a11a0 AP_NavEKF: use AHRS vehicle class for sideslip calculation
Pair-Programmed-With: Paul Riseborough <p_riseborough@live.com.au>
2014-04-21 18:13:12 +10:00
Andrew Tridgell 5acd17b843 AP_NavEKF: cleanup some build warnings
Pair-Programmed-With: Paul Riseborough <p_riseborough@live.com.au>
2014-04-21 18:13:12 +10:00
priseborough bd28cdbdcf AP_NavEKF: Improved magnetometer consistency checks
A magnetometer axis that fails the innovation consistency check will cause
all axes not to be used. If this condition continues for 10 seconds, a
magnetometer timeout condition will be declared. When the timeout has
occurred, if it is not a fly forward vehicle, then individual channels
will be used again, but with a reduced weighting.
2014-04-21 16:31:31 +10:00
Andrew Tridgell 610a930612 AP_NavEKF: catch covarience errors and reset filter
this catches covariance values beyond a reasonable limit and resets
the filter is they happen
2014-04-21 15:37:08 +10:00
Andrew Tridgell 4756dbee84 AP_NavEKF: fixed millisecond subtraction for rollover
Pair-Programmed-With: Paul Riseborough <p_riseborough@live.com.au>
2014-04-21 13:16:20 +10:00
Andrew Tridgell 68f1ae3036 AP_NavEKF: fixed some matlab ! -> ~ typos
Pair-Programmed-With: Paul Riseborough <p_riseborough@live.com.au>
2014-04-20 21:44:37 +10:00
Andrew Tridgell 4abc2999a6 AP_NavEKF: start with a wind estimate of 3m/s, when no direct measurement
this will cope better with users with low roll/pitch gains, to ensure
they get enough control on takeoff

Pair-Programmed-With: Paul Riseborough <p_riseborough@live.com.au>
2014-04-13 19:42:23 +10:00
priseborough d745dc2b6f AP_NavEKF : Increased position gate default to reduce impact of accel errors
Flight testing with windup turns has shown that the position gate threshold
can be tripped with good GPS data causing position jerks. This increases the
initial GPS glitch rejection threshold to effectively 5m when using the
default POSNE_NOISE value of 0.5m.
2014-04-13 19:37:22 +10:00
priseborough 188bea6bab AP_NavEKF : Enable calc of wind velocity when not using airspeed sensing
This patch also cleans up the logic associated with use of the synthetic
sideslip measurement so that it can never be used for a non fly-forward
vehicle type

This patch adds functionality that initialises the wind-speed vector to the
reciprocal of the ground speed vector, and scaled to 6 m/s. On average this gives
a better initial wind velocity estimate on launch by assuming:

a) launch will be into wind
b) wind speed is equal to global average

It also helps prevent a headwind causing initial underestimation of airspeed
causing high autopilot gains and limit cycles on climb-out, until first
turn when the EKF is able to estimate the wind.
2014-04-13 19:37:19 +10:00
Emile Castelnuovo 25f1c5774f AP_NavEKF: added #defines for VRBRAIN board 2014-04-08 16:19:19 +10:00
priseborough db043744a4 AP_NavEKF : Reduce Z accel bias process noise to provide a more stable estimate 2014-04-07 21:08:25 +10:00
priseborough 1f8b5a6d23 AP_NavEKF : Tighten GPS velocity glitch gate default setting for plane 2014-04-07 21:08:15 +10:00
priseborough 0c2489b07b AP_NavEKF : Fix bug in logging of airspeed innovation consistency ratio 2014-04-07 21:01:00 +10:00
priseborough 95c83255d7 AP_NavEKF : adjust default values for accelerometer process noise
Slows down estimate and allows for smaller values to be set
2014-04-07 21:00:43 +10:00
Andrew Tridgell 07d621c4be AP_NavEKF: used state structure in more places
makes the code a bit easier to read

Pair-Programmed-With: Paul Riseborough <p_riseborough@live.com.au>
2014-04-04 21:30:16 +11:00
priseborough aa5335b16e AP_NavEKF : Improved GPS position glitch handling
When using GPS after previously rejecting it, the GPS position will
always be offset if outside the specified glitch radius. This was the
original intent of the design and makes handling of glitches smoother.

It has been tested on replay using glitchy flight data
2014-04-04 21:01:22 +11:00
priseborough b1786cf1e5 AP_NavEKF : Do not reset on GPS velocity timeout if good position data 2014-04-04 21:01:20 +11:00
priseborough d25883f712 AP_NavEKF : Limit rate of Z accel bias adaptation
Aliasing can causes the bias estimate to fluctuate very rapidly as it tries
to keep up, which degrades the benefit of switching between
accelerometers to avoid aliasing.

This patch give a much more stable bias estimate during aliasing, and
allows the bias to adapt at a maximum rate of 1.0 m/s2 in 50 seconds
2014-04-04 21:01:18 +11:00
priseborough 36b3cbc365 AP_NavEKF : Relax aliasing check limits
This reduces the chance of noisy data inhibiting GPS glitch protection
2014-04-04 21:01:15 +11:00
priseborough 0ae736c3a0 AP_NavEKF : clean up convoluted logic used in sensor health checks
This doesn't change the behavior, but does make the code easier to
understand
2014-04-04 21:01:13 +11:00
Andrew Tridgell cd3038fabd AP_NavEKF: fixed return of offset in getVariances() 2014-04-03 07:49:06 +11:00
Andrew Tridgell a7f213a5c5 AP_NavEKF: use pythagorous2() 2014-04-01 22:13:03 +11:00
priseborough 04036d7777 AP_NavEKF : Updated GPS glitch protection logic
This adds new functionality to the detection and compensation of GPS
glitches:

1) A maximum allowable innovation is calculated using the GPS noise
parameter multiplied by the gate, with an additional component allowing
for growth in position uncertainty due to acceleration error since
the last valid measurement
2) Includes per vehicle type values for the acceleration error limit
3) If the innovation length exceeds the maximum allowable, no fusion occurs
4) If no fusion has occurred for long enough such that the position uncertainty
exceeds the maximum set by a per vehicle parameter or a maximum time, an offset
is applied to the GPS data to so that it matches the value predicted by the filter
5) The offset is never allowed to be bigger than 100m
6) The offset is decayed to zero at a rate of 1.0 m/s to allow GPS jumps to
be accommodated gradually
7) The default velocity innovation gate has been tightened up for copter and rover
8) The variance data logging output has been updated to make it more useful
2014-04-01 21:22:14 +11:00
Andrew Tridgell 5a2e84e792 AP_NavEKF: changes for new GPS API 2014-04-01 06:38:24 +11:00
priseborough 9c5f564dc5 AP_NavEKF : Fixes bug in initial earth magnetic field states
The calculation for these states was not being bias corrected
2014-03-30 07:43:52 +11:00
priseborough e1819bb53a AP_NavEKF : Add initial parameter defaults for Copter, Rover and Plane 2014-03-29 14:06:43 +11:00
priseborough 55c60b8f07 AP_NavEKF : Reduce Magnetometer innovation consistency check threshold 2014-03-26 21:29:47 +11:00
priseborough 45b1a2fa46 AP_NavEKF : Reduce GPS position innovation consistency fail threshold
This patch reduces the maximum acceptable GPS jump from approximately 16 to 8 metres
This will provide copters with more protection for close in loiter situations
2014-03-26 21:29:45 +11:00
Andrew Tridgell bafc664750 AP_NavEKF: use APM_BUILD_TYPE() macro 2014-03-26 12:42:11 +11:00
Andrew Tridgell e3792f9b26 AP_NavEKF: added a mechanism for per-vehicle-type defaults in EKF 2014-03-26 12:30:17 +11:00
priseborough 17cdac7bc8 AP_NavEKF : Clean up angle and mag field initialisation
This path reduces duplicated code, eliminates unused variables and
causes the earth magnetic field states to be reset when exiting static mode
which will occur every time copter is armed. This enables copters to be
powered on and initialised inside vehicles or houses, without bad earth
field values affecting flight.
2014-03-24 19:54:48 +11:00
priseborough 7ae86b3979 AP_NavEKF : Track baro height observations pre-arm
This prevents copter from failing the pre-arm height discrepancy test
2014-03-23 18:25:50 +11:00
priseborough 7780d55788 AP_NavEKF : Prevent large magnetic field adaptations early in flight 2014-03-22 19:55:26 +11:00
Paul Riseborough f7007569d1 AP_NavEKF : Fix bug that limits copter sensor delay compensation to 125
msec
2014-03-21 21:52:20 +11:00
Paul Riseborough b2c0979947 AP_NavEKF : Fixes bug that causes accel bias to diverge in static mode, preventing copter arming 2014-03-21 21:49:50 +11:00
Paul Riseborough 8a2d16d13d AP_NavEKF : modifed Zaccel bias noise parameter to prevent unstable bias estimate 2014-03-20 08:50:00 +11:00
Paul Riseborough dacba5d911 AP_NavEKF : Update default tuning parameters (for plane use) 2014-03-14 06:07:58 +11:00
Paul Riseborough d0828d9c15 AP_NavEKF : Prevent bad user parameter causing incorrect GPS fusion 2014-03-14 06:07:58 +11:00
Paul Riseborough a24bfc1b8a AP_NavEKF : Use synthetic sideslip fusion during GPS denied operation with airspeed 2014-03-14 06:07:57 +11:00
Paul Riseborough 35811758d7 AP_NavEKF : Update comments and remove un-used function declarations 2014-03-14 06:07:57 +11:00
Paul Riseborough 784034170d AP_NavEKF : increased useage of helper functions 2014-03-10 21:54:03 +11:00
Paul Riseborough 7b3130cfcc AP_NaVEKF : Enable operation without airspeed and compass 2014-03-10 21:53:09 +11:00
Paul Riseborough 3a5acb9cea AP_NavEKF : improved on-ground, in-air check and GPS yaw alignment 2014-03-10 14:07:34 +11:00
Paul Riseborough b47a11edf6 AP_NavEKF : improved static and on-ground mode selection logic 2014-03-10 04:39:59 +11:00
Paul Riseborough 15a44571c2 AP_NavEKF : enable operation without a compass for planes 2014-03-09 20:01:45 +11:00
Paul Riseborough 2019708056 AP_NavEKF : Make all compass use autodetect 2014-03-09 19:59:19 +11:00
Paul Riseborough e485b246e7 AP_NavEKF : update comments 2014-03-09 19:59:18 +11:00