Commit Graph

247 Commits

Author SHA1 Message Date
Jonathan Challinger a03fa2d3cf AP_AHRS: use exact matrix for trim rotations 2016-10-13 10:02:13 +11:00
masierra 8fc494cfcd AP_AHRS_DCM: changed estimate to use prev values for dir & vel 2016-06-06 15:26:51 -07:00
Ricardo de Almeida Gonzaga 2bf9aa94ad AP_AHRS: Fix typos 2016-05-13 19:20:06 -03:00
dgrat 6d3b491c02 AP_Math: Replace is_equal with a type safe template function
It makes sense to consider also other floating point types.
2016-05-10 11:41:26 -03:00
dgrat 41661f815f AP_Math: Replace the pythagorous* functions with a variadic template
The new function can deal with a variable number of function parameters.
Additionally, I renamed the functions to norm(), because this is the
standard name used in several other projects.
2016-05-10 11:41:26 -03:00
Caio Marcelo de Oliveira Filho 55e61538b3 AP_AHRS_DCM: use millis/micros/panic functions 2015-11-20 12:28:45 +09:00
Lucas De Marchi da86e29c27 AP_AHRS: remove check for AVR CPUs
Remove the checks for HAL_CPU_CLASS > HAL_CPU_CLASS_16 and
HAL_CPU_CLASS >= HAL_CPU_CLASS_75. Corresponding dead code will be
removed on separate commits.
2015-11-04 12:14:14 +11:00
Andrew Tridgell 79d85f7e10 AP_AHRS: wait for up to 10 samples to get a valid accel vector
the initial accel vectors can be invalid
2015-10-21 09:09:11 +11:00
Jonathan Challinger c35605fa04 AP_AHRS_DCM: align tilt during initialization 2015-10-21 08:34:02 +11:00
Gustavo Jose de Sousa 84f811fe76 AP_AHRS: use compass get_{field,offsets}() functions
Both functions are equivalent, so we're going to simply use
get_{field,offsets}() instead of get_{field,offsets}_milligauss().
2015-10-15 19:56:00 +09:00
Andrew Tridgell 06c0ad987e AP_AHRS: fixed divide by zero in SITL
fixes issue#2875
2015-09-24 16:49:22 +10:00
Andrew Tridgell 0677c2c80c AP_AHRS: run astyle for formatting 2015-09-23 17:31:00 +10:00
Staroselskii Georgii 4b948f5bb1 AP_AHRS: make DCM use milligauss 2015-09-09 10:38:16 +10:00
Randy Mackay 7f46cc9059 AHRS_DCM: integrate INS use_accel 2015-08-19 16:44:19 +09:00
Gustavo Jose de Sousa 54d5277842 AP_AHRS: standardize inclusion of libaries headers
This commit changes the way libraries headers are included in source files:

 - If the header is in the same directory the source belongs to, so the
 notation '#include ""' is used with the path relative to the directory
 containing the source.

 - If the header is outside the directory containing the source, then we use
 the notation '#include <>' with the path relative to libraries folder.

Some of the advantages of such approach:

 - Only one search path for libraries headers.

 - OSs like Windows may have a better lookup time.
2015-08-11 16:28:42 +10:00
Andrew Tridgell 7e2e78c1af AP_AHRS: protect against zero deltat in DCM
fixes issue #2657
2015-08-05 15:21:00 +10:00
Andrew Tridgell 9c776736c1 AP_AHRS: use delta_velocity and delta_angle in DCM
this prevents an aliasing effect by using the correct delta velocity
time value for each accelerometer sample used
2015-07-30 11:04:31 +10:00
Andrew Tridgell 7a76f72bf5 AP_AHRS: added uptime_ms() interface 2015-05-20 15:22:14 +10:00
Andrew Tridgell 3529e02675 AP_AHRS: if we have 3 gyros then only use first two
the 3rd gyro on a PH2 has a lot more noise as it is not vibration
isolated
2015-05-09 21:00:49 +10:00
Peter Barker 463270e0ee AP_AHRS: avoid FPE when we don't have a compass reading 2015-05-05 15:02:35 +10:00
Andrew Tridgell 4d4a607b80 AP_AHRS: revert AP_Math class change 2015-05-05 13:27:05 +10:00
Tom Pittenger 20f47417d5 AP_AHRS: compiler warnings: apply is_zero(float) or is_equal(float) and float to doubles 2015-05-05 13:26:55 +10:00
Andrew Tridgell 6bfca648b9 AP_AHRS: raise DCM P gains when disarmed for first 20 seconds 2015-04-28 14:07:39 +10:00
Tom Pittenger e28c555889 AHRS_DCM: fix compile warnings re float constants
Also fix example sketch
2015-04-24 12:26:08 +09:00
Paul Riseborough 5184bca87f AP_AHRS: Prevent DCM reporting good tilt error when inverted 2015-04-23 20:35:39 +09:00
Paul Riseborough ea8217bd3a AP_AHRS: Reduce time constant on filtering of DCM error reporting
Reduces time constant from 2 to 1 second to make data more useful for pre-flight alignment checks by the EKF
2015-04-23 20:35:35 +09:00
Andrew Tridgell a0969905ce AP_AHRS: make get_error_rp() and get_error_yaw() const
this makes them usable by multiple consumers, and allows use by EKF
2015-04-21 21:42:17 +10:00
Andrew Tridgell 585a105128 AP_AHRS: use compass->last_update_usec() 2015-03-14 12:31:50 +11:00
Andrew Tridgell 68f64fa11c AP_AHRS: make the healthy() method const 2015-02-01 14:13:52 +11:00
Andrew Tridgell ed0a56cc3c AP_AHRS: cope with the changed semantics of airspeed.use() 2015-01-20 11:27:58 +11:00
Jonathan Challinger 4975cefd84 AP_AHRS_DCM: update _accel_ef_blended 2014-12-05 19:40:06 +09:00
Randy Mackay dffcfb42bc AHRS: add reset_gyro_drift method 2014-10-28 20:25:33 +09:00
Randy Mackay 39c8535223 AHRS_DCM: sanity check AHRS_RP_P and AHRS_YAW_P 2014-10-21 21:41:41 +09:00
Andrew Tridgell 270bac4472 AP_AHRS: make get_position() const
This allows use from within AP_Mission
2014-10-20 08:36:20 +11:00
Andrew Tridgell 4ad643b233 AP_AHRS: use a common function for updating the CD values
this ensures the wrapping of yaw is consistent between the 3 use cases
2014-10-15 13:18:08 +11:00
Andrew Tridgell 63c06ea2af AP_AHRS: fixed calls to DCM in parent class
use_compass() and reset() are common to AP_AHRS_DCM and
AP_AHRS_NavEKF. As AP_AHRS_NavEKF is a child of AP_AHRS_DCM, when we
call use_compass() from within AP_AHRS_DCM we actually end up calling
AP_AHRS_NavEKF::use_compass().

This has the effect of disabling the compass in DCM when EKF is active
and EKF has decided not to use the compass. That means that the DCM
yaw (and in fact the whole attitude) can get badly off while EKF is
enabled, making DCM an ineffective fallback if EKF fails.

The fix is to call the specific class versions of use_compass() and
reset()
2014-10-15 10:12:50 +11:00
Randy Mackay 85eee31510 AHRS: rename ekfNotStarted method to initialised
Also created default implementation in AP_AHRS class so AP_AHRS_DCM does
not need to implement it.
2014-10-02 14:40:54 +09:00
priseborough 7cea7c6a18 AP_AHRS : add method to report if EKF is waiting to start 2014-10-02 14:38:29 +09:00
Przemek Lekston ae4814a773 AP_AHRS_DCM.cpp: changed the direction of position projection to ensure correct behavious in crosswind 2014-08-07 12:34:30 +10:00
Andrew Tridgell 6a275372dd AP_AHRS: ensure get_position() fills in flags 2014-07-25 11:40:16 +10:00
Andrew Tridgell b3c1e515dc AP_AHRS: when no accel info available in buffer use current value
this prevents an initialisation error, and is reasonable in flight too

Pair-Programmed-With: Paul Riseborough <p_riseborough@live.com.au>
2014-05-15 22:19:54 +10:00
Andrew Tridgell 315290029a AP_AHRS: fixed check of accel sensor health
we need to check health of each accelerometer separately
2014-05-15 22:18:56 +10:00
Andrew Tridgell 1a05c27bbb AP_AHRS: added healthy() function
this will be used to report when the AHRS subsystem becomes unhealthy
2014-05-15 21:14:21 +10:00
Andrew Tridgell 4d24a86088 AP_AHRS: prevent a infinity value 2014-04-21 15:37:07 +10:00
Andrew Tridgell f07e4dee52 AP_AHRS: convert to new GPS API 2014-04-01 06:38:24 +11:00
Andrew Tridgell b53496d470 AP_AHRS: choose the best accelerometer at each drift correction step
this greatly reduces the impact of aliasing on accelerometers by
choosing the accelerometer that produces the smallest error term in
DCM. The difference can be quite dramatic on the Pixhawk.
2014-02-27 09:41:28 +11:00
Andrew Tridgell 0b45d2bc06 AP_AHRS: removed the AHRS_GPS_DELAY parameter
the best value has turned out to be 1, and tweaking it has not turned
out to be useful, so this simplifies the code in preparation for
adding the anti-aliasing handling with multiple accelerometers
2014-02-27 08:57:44 +11:00
Jonathan Challinger f321a5f241 AP_AHRS: Change airspeed_estimate to const in children of AP_AHRS
Allows roll/pitch controllers to use DCM's airspeed estimate. Thanks to Kevin Hester for assistance in finding this.
2014-02-25 18:49:16 +11:00
Andrew Tridgell eedd88c2ec AP_AHRS: give zero lat/lng and baro alt if no position yet in DCM 2014-02-15 09:25:40 +11:00
Andrew Tridgell 25ef0d5a7b AP_AHRS: don't allow get_velocity_NED() and get_relative_position_NED() without EKF
this avoids some linking issues, plus the functions are inaccurate
without EKF
2014-02-15 05:48:24 +11:00
Andrew Tridgell c62ccce9d8 AP_AHRS: make estimate_wind() public
this avoids it linking into copter
2014-02-15 05:48:24 +11:00
Paul Riseborough 08267cea87 AP_AHRS: Scheduling for yaw gain to reduce atitude errors in turning flight 2014-02-15 05:48:22 +11:00
Andrew Tridgell 5d43a1d704 AP_AHRS: added inertial nav interfaces to AHRS 2014-02-15 05:48:16 +11:00
Andrew Tridgell 392995ef84 AP_AHRS: make AHRS handle altitude
AHRS now holds the home position
2014-02-15 05:29:47 +11:00
Randy Mackay 6946d68318 AHRS_DCM: call update_trig 2014-02-08 18:16:42 +09:00
Paul Riseborough f2c2811ef3 AP_AHRS & AP_Math: fixed bug in use of AHRS_TRIM parameters 2014-01-19 07:19:43 +11:00
Andrew Tridgell baa4ecc2ea APA_AHRS: update for compass API change 2013-12-09 17:34:07 +11:00
Andrew Tridgell b248cc0868 AP_AHRS: fixed a build warning 2013-11-23 21:44:56 +11:00
Andrew Tridgell 6ed493b10f AP_AHRS: added attitude_reset() method for HIL_SENSORS 2013-11-23 18:50:56 +11:00
Andrew Tridgell 4f871c87f1 AP_AHRS: detect and try to cope with bad accels 2013-11-07 13:54:16 +11:00
Andrew Tridgell 02d6f012ce AP_AHRS: added accel sum delay buffer to account for GPS lag 2013-11-04 21:21:42 +11:00
Andrew Tridgell d31e557983 AP_AHRS: save memory and reduce pointer references
use a refence for ins, and don't save gyro and accel between updates
2013-11-04 21:21:37 +11:00
Andrew Tridgell cb52b6f367 AP_AHRS: removed limit on normalisation of accel reference vectors
this could lead to a bias in the accel drift correction
2013-11-04 21:20:41 +11:00
Andrew Tridgell 31eaaada62 AP_AHRS: removed vertical G limit on GPS velocity correction
this limit could lead to a bias in the accel drift correction, and is
frequenctly exceeded
2013-11-04 21:20:41 +11:00
Andrew Tridgell a7931b1581 AP_AHRS: fixed wrapping bug in GPS based heading error
this bug could cause the GPS based yaw to use an expensive reset far
too often
2013-11-04 21:20:41 +11:00
Andrew Tridgell 17b27a47de AP_AHRS: prevent GPS yaw resets on compass errors
when we switch from compass heading to GPS heading we don't want to
trigger a sudden GPS yaw reset
2013-11-04 21:20:41 +11:00
Andrew Tridgell d305dd5946 AP_AHRS: debounce the GPS/compass consistency test
we will only consider the compass inconsistent with GPS if it is off
for more than 2 seconds
2013-10-23 09:40:42 +11:00
Andrew Tridgell 587fb58720 AP_AHRS: fixed license text
APM is under GPL, not LGPL
2013-08-30 13:01:32 +10:00
Andrew Tridgell 0d36832b82 AP_AHRS: use const reference not pointers for locations
this makes life easier for the new AP_Mission library

Pair-Programmed-With: Brandon Jones <brnjones@gmail.com>
2013-08-05 10:24:12 +10:00
Andrew Tridgell ec73fadc45 AP_AHRS: added true airspeed support in AHRS
use true airspeed for wind calculations, and allow other drivers to
ask for the current ratio
2013-07-22 12:50:01 +10:00
Randy Mackay 0325ad5d0d AP_AHRS: use rotateXY for speed
Saves 0.1ms at 100hz
2013-07-20 18:00:36 +09:00
Andrew Tridgell 086e8f80dc AP_AHRS: fixed spin rate gain conversion from degrees to radians
fixes issue #433

Thanks Jurgen!
2013-07-13 12:36:25 +10:00
Andrew Tridgell 279f6d00f0 AP_AHRS: changes for GPS field changes 2013-07-10 14:04:22 +10:00
tobias 1bf135b36f AP_AHRS: make some more functions const 2013-07-08 12:07:50 +10:00
Andrew Tridgell 7d42a0562d AP_AHRS: cope better with large GPS yaw changes
this should cope better with bungee launches when using only GPS for
yaw.
2013-06-25 12:44:26 +10:00
Andrew Tridgell 14628990e6 AP_AHRS: make wind estimation configurable
rover doesn't want it
2013-05-24 11:21:42 +10:00
Andrew Tridgell 6f1cee6406 AP_AHRS: fixed position estimate with 2D fix or low satellite count
we should still use the GPS for position fixes when we have a low
number of satellites, but we should stop using it for velocity
estimates and attitude correction.
2013-05-07 10:52:14 +10:00
Randy Mackay ceda7d26b0 AHRS: add correct_centrifugal and flags structure 2013-05-06 15:32:06 +09:00
Andrew Tridgell 38fc0e61c6 AP_AHRS: optimise yaw drift correction
use new vector2 cross product, and factor out the z component of a dcm
mul_transpose() to reduce the number of floating point operations for
a yaw drift correction cycle
2013-05-05 13:51:45 +10:00
Randy Mackay ee2daf25b6 AHRS: perf improvement by caching declination vector 2013-05-05 12:58:43 +10:00
Andrew Tridgell 943a1d8c8d AP_AHRS: added AHRS_GPS_MINSATS option
if the number of visible satellites is below AHRS_GPS_MINSATS then
don't use the GPS for acceleration correction for attitude
2013-05-05 12:48:01 +10:00
Andrew Tridgell ba83950fc4 libraries: replace constrain() with constrain_float()
this makes the type much more obvious. Thanks to Tobias for the
suggestion.
2013-05-02 10:25:40 +10:00
Andrew Tridgell f5d6fb6216 AP_AHRS: added _kp gain reduction for catapult launch
this should reduce the tendency of aircraft to nose down hard on
initial launch at high g
2013-04-28 14:47:59 +10:00
Andrew Tridgell fd2cd0d1c2 DCM: fixed formatting 2013-04-23 08:57:44 +10:00
jschall 610069e729 DCM: fixed airspeed bug
we incorrectly went via the wind estimate when we had a working airspeed sensor
2013-04-23 08:57:44 +10:00
Andrew Tridgell a4d25f5a82 AHRS: removed AHRS_BARO_USE option
this option has caused users too much trouble. The vertical velocity
is too noisy from the baro
2013-04-15 10:52:31 +10:00
Andrew Tridgell 8459da202c AP_AHRS: prevents compass flyaways for plane and rover
this switches to the GPS for yaw if the compass has dragged us off by
more than 45 degrees from the GPS heading, and the wind speed is less
than 80% of the ground speed.
2013-03-29 13:48:25 +11:00
Randy Mackay 24044dc0c4 AHRS: add support for GPS fix type 2D 2013-03-27 11:41:43 +09:00
James Bielman 5631f865b2 Update floating point calculations to use floats instead of doubles.
- Allows use of hardware floating point on the Cortex-M4.
- Added "f" suffix to floating point literals.
- Call floating point versions of stdlib math functions.
2013-01-16 13:52:01 +11:00
Andrew Tridgell 3ac3aeb1b1 AHRS: fixed build on ARM 2013-01-02 14:45:09 +11:00
rmackay9 1c08f176ea AP_AHRS: add get_accel_ef method to return earth frame accelerometer values for use in ArduCopter's inertial nav and accel based throttle 2013-01-02 09:11:25 +11:00
Andrew Tridgell ceb3f577d8 libraries: use new math functions 2012-12-20 14:53:22 +11:00
Andrew Tridgell 8b6ad6d559 SITL: removed SITL_debug()
not needed any more
2012-12-20 14:51:36 +11:00
Andrew Tridgell 5840ded767 AHRS: removed constrain() defines 2012-12-20 14:51:34 +11:00
Pat Hickey 9bf69d4e0d AP_AHRS: port to AP_HAL 2012-12-20 14:51:29 +11:00
Andrew Tridgell 8561f08b2f AP_AHRS: prevent a large delta_t from affecting DCM solution
this should fix large changes in attitude directly after arming
ArduCopter
2012-11-13 15:33:10 +11:00
rmackay9 83ae8e47be AP_AHRS: replace IMU with INS and add roll and pitch trim 2012-11-07 19:20:32 +09:00
Andrew Tridgell fe47990dab AP_AHRS: removed the 6 sats min
this would put us into dead-reckoning mode
2012-11-06 14:26:49 +11:00
Andrew Tridgell 6a24bdec05 AP_AHRS: require at least 6 satellites to use the GPS for velocity
logs of a recent flight show the velocity estimate can be very poor if
the GPS can see 5 satellites or less
2012-11-05 20:07:37 +11:00
Andrew Tridgell ea40432235 AP_AHRS: use GPS vertical velocity when available 2012-11-05 14:58:40 +11:00
Andrew Tridgell 00bf548f87 AHRS: limit wind speed estimate changes
sudden yaw changes can cause bad wind estimates
2012-10-11 11:51:24 +11:00
Andrew Tridgell ccf8ba3ce9 DCM: limit the contribution of the baro to vertical acceleration
limit to a max of 0.5g
2012-09-20 17:34:32 +10:00
Andrew Tridgell fba1692d69 AHRS: added AHRS_BARO_USE parameter
allow disabling of the use of the barometer for vertical acceleration
compensation
2012-09-12 14:42:04 +10:00
Andrew Tridgell de28cc8b28 AHRS: added AHRS_WIND_MAX option
this allows APM to cope better with airspeed sensor failure, but
ensuring airspeed stays within AHRS_WIND_MAX of ground speed
2012-09-08 11:37:07 +10:00
Andrew Tridgell 2be785899b AHRS: added airspeed_estimate() function
this allows the APM code to use an airspeed estimate for navigation
2012-08-25 17:49:26 +10:00
uncrustify 31a4442904 uncrustify libraries/AP_AHRS/AP_AHRS_DCM.cpp 2012-08-21 19:19:51 -07:00
Andrew Tridgell 134cd51d17 AHRS: moved var_info[] into top level AP_AHRS class 2012-08-21 15:58:09 +10:00
Andrew Tridgell ac72db8f00 AHRS: added set_fast_gains() method
this will be used by arducopter on the ground
2012-08-21 15:38:06 +10:00
Andrew Tridgell 14cdbd36cb AHRS: check for bad values in the error before they can affect DCM
this should fix the DCM renorm errors in autotest, probably caused by
bad climb rates
2012-08-18 13:54:11 +10:00
Andrew Tridgell d9cc967508 AHRS: force an extra read of the compass on startup
the first read from the compass can be bad. This ensures we have a
good value when getting the initial AHRS yaw.

Thanks to Randy and Jason for the bug report!
2012-08-17 17:57:39 +10:00
Andrew Tridgell 19a5d11669 AHRS: use airspeed for wind in forward flight
when not turning we can use the airspeed sensor directly to calculate
the wind speed.
2012-08-12 10:54:25 +10:00
Andrew Tridgell f5b7ae213c AHRS: added AHRS_GPS_USE parameter
this allows for the GPS to be disables for position updates, which
allows for testing dead-reckoning
2012-08-11 22:06:03 +10:00
Andrew Tridgell 779dacfd24 AHRS: added wind estimation code
this allows us to estimate the wind while we have GPS lock, then use
that estimate in the long term dead reckoning
2012-08-11 22:06:03 +10:00
Andrew Tridgell af4071894e AHRS: added long-term dead-reckoning
this uses airspeed (if available) or last GPS ground speed to update
our position estimate in AHRS
2012-08-11 12:00:31 +10:00
Andrew Tridgell 898a5af692 AP_Param: update AHRS for new constructor syntax 2012-08-08 12:11:57 +10:00
rmackay9 468170b589 AP_AHRS_DCM: moved var_info to belong to AP_AHRS_DCM instead of AP_AHRS 2012-07-28 14:16:15 +09:00
Jonathan Challinger 9cd98e79dd AHRS: normalise GA_b before computing error vector only if too large
When GA_b is small the direction of the vector is unreliable, so
normalising can exacerbate the error in the direction
2012-07-23 17:16:50 +10:00
Andrew Tridgell 5f5ab9c07c AHRS: if we don't have gps correction enabled, zero the yaw correction 2012-07-20 17:21:04 +10:00
Andrew Tridgell c937738732 AHRS: allow the gps/accelerometers to control yaw when rolled
this solves a problem with yaw estimation when at high roll angles,
when the compass code becomes ineffective
2012-07-20 11:50:04 +10:00
Michael Oborne a469682b7b fix param config names 2012-07-14 15:34:15 +08:00
Andrew Tridgell 0f9fb2c64b AHRS: added AHRS_GPS_GAIN parameter
this allows control of how much GPS velocity information is used in
doing centripetal correction in DCM
2012-07-10 16:22:48 +10:00
Andrew Tridgell 302696951a AHRS: make the yaw independent drift correction optional and disable
the new correction algorithm copes poorly with gyro drift, leading to
signification attitude errors in the face of drift
2012-07-06 15:11:30 +10:00
Andrew Tridgell 8c5ef3e60f AHRS: only enable barometer for AHRS if it is smooth enough
if we used less than 5 samples to compute the pressure then don't use
it for climb rate
2012-07-05 16:29:21 +10:00
Andrew Tridgell 2cd6da2539 AHRS: only use GPS for yaw when compass is not being used
this avoids having two competing controllers
2012-07-05 13:00:46 +10:00
Andrew Tridgell adfa97b6f8 AHRS: enable barometer for vertical velocity
this re-enables the barometer for vertical velocity information
for drift correction, now that we have a better filter
on the climb rate
2012-07-05 13:00:46 +10:00
Andrew Tridgell 3849ca8b5c AHRS: make DCM drift correction not rely on accurate yaw
this uses a new formulation of the GPS based drift correction from
Bill Premerlani that rotates the error vector to avoid relying on
accurate yaw. This means we should get accurate roll/pitch correction
even with lots of magnetometer interference

It also makes it possible to fly a multicopter with no compass. It can
even navigate and correct yaw (slowly!)
2012-07-04 17:00:40 +10:00
Andrew Tridgell 1314e4f872 AHRS: make P gain on PI roll/pitch controller tunable
this is to make it easier for Craig and Alan to tune
2012-07-04 12:42:46 +10:00
Andrew Tridgell 16c55c64d4 AHRS: don't add the P terms in _omega
this can lead feedback via the _P_gain()
2012-06-29 15:10:51 +10:00
Andrew Tridgell 37fc6c46b9 AHRS: disable barometer for vertical acceleration
this seems to have been the cause of the 'flips' seen by Marco and
others. Testing by Craig and Alan shows that the flips are gone when
the barometric acceleration is removed.

It looks like a 5 point average filter is not enough to keep the
vertical acceleteration noise low. With high noise in the z axes, the
x and y axes are scaled back when the ge vector is normalised.
2012-06-28 11:12:49 +10:00
Andrew Tridgell 58c4d458dc AHRS: re-instate new DCM drift correction code
This reverts commit 078489638d47fbaffde7c51249e36b5a8fc4ef9d.
2012-06-28 11:09:22 +10:00
Andrew Tridgell fd241692d0 AHRS: revert to the old drift correction algorithm
we need to work out why Craigs quad flipped today before we enable
this new drift correction
2012-06-27 18:16:41 +10:00
Andrew Tridgell 8e044a560b AHRS: include P term in omega
thanks to Jon for suggesting this
2012-06-27 16:01:50 +10:00
Andrew Tridgell 37e2f2ee2c AHRS: implement spin rate limits
this follows the method that Bill developed in his fastRotations
paper. We've demonstrated that this is indeed needed in APM, as we
were able to produce the 'dizzy' effects in both the ArduPlane and
ArduCopter simulator
2012-06-27 16:01:50 +10:00
Andrew Tridgell e4a245179c AHRS: cope with copters with no compass
if a copter doesn't have a compass, we can't use the GPS for gyro
drift correction
2012-06-27 16:01:50 +10:00
Andrew Tridgell 3a41ad8e7c AHRS: normalize the ge vector in drift correction, and use barometer
The normalisation ensures the error term scales uniformly with
different accelerations.

The barometer is used for vertical acceleration estimation
2012-06-27 16:01:50 +10:00
Jonathan Challinger d230690b7b AHRS: brought DCM more inline with Bill's implementation
omega_I applied continuously. _ki larger. Stop integrating when _omega.length()>20

The key change was the scaling of ge to ensure the error is not
quadratic
2012-06-27 16:01:49 +10:00
Andrew Tridgell d4c8041c51 AHRS: first successful version of Bills new drift correction system
This makes 3 major changes:

 1) fixes the scaling of the yaw drift correction term to fix the time
 constant

 2) don't integrate the mag vector over multiple readings

 3) accumulate omega_I changes over 15 seconds before applying, to try
 to prevent omega_I picking up short term responses
2012-06-27 16:01:49 +10:00
Andrew Tridgell 0f5c22bd8e AHRS: implement Bills new drift correction algorithm
this is an initial implementation of this paper:

  http://gentlenav.googlecode.com/files/RollPitchDriftCompensation.pdf
2012-06-27 16:01:49 +10:00
Andrew Tridgell f274df454a DCM: fixed a bug when using GPS for yaw correction
When using GPS for yaw correction we need to apply the x and y omegaI
corrections from the _omega_I_sum in the period before we get to the
minimum ground speed for GPS yaw correction. Otherwise we get a large
sudden omega_I change on takeoff.
2012-05-21 12:15:06 +10:00
Adam M Rivera 3309dec205 AP_AHRS_DCM.cpp: Added comments that follow the new parse structure 2012-04-25 12:00:42 -05:00
Andrew Tridgell 2a3af369b6 DCM: buffer omega_I changes over 10 seconds
this buffers up _omega_I changes in _omega_I_sum over a period of 10
seconds, applying the slope limit only when _omega_I_sum is
transferred to _omega_I.

The result is a huge improvement in the ability of _omega_I to track
gyro drift over the long term.
2012-04-23 12:13:25 +10:00
Andrew Tridgell f27d85cb8d DCM: drop the 'drop z' method
the 'drop z' method reduced the impact of noise on omegaI, but it also
made us more sensitive to errors in accelerometer calibration and
scaling, as demonstated by the logs from Gabor here:

  http://diydrones.com/xn/detail/705844:Comment:834373

Simulation testing shows that the other noise suppression methods
applied in the DCM code, in particular the slope limiting on omegaI
the removal of the weighting and the upcoming use of a _omega_I_sum
buffer have reduced the impact of noise enough that we can now safely
include z in the acceleration calculation.
2012-04-23 12:13:24 +10:00
Andrew Tridgell 8e90aeea4e AHRS: added AHRS_YAW_P parameter
this allows users to change the yaw gain in DCM
2012-04-16 20:55:13 +10:00
Andrew Tridgell b549b88e5e AHRS: fixed error_yaw reporting with 2 MAVLink connections
when a user first connects with USB, and later switches to the
telemetry port without restarting we were getting zero for error_yaw
in the logs, as AHRS.get_error_yaw() was being called twice.

This ensures we give the last value after the counter is reset
2012-03-29 12:39:53 +11:00
Andrew Tridgell 4f82134a5e DCM: use the new rotate() method from AP_Math
this allows us to use a tested and optimised rotation method
2012-03-19 17:29:02 +11:00
Andrew Tridgell d4bb068d5b AHRS: adapt the DCM library to the AHRS framework 2012-03-19 17:29:02 +11:00
Andrew Tridgell 9d75ffeba1 AHRS: rename DCM and Quaternion implementions ready for AHRS class
this is the first step to creating a general AHRS class for ArduPilot
2012-03-19 17:29:01 +11:00