diff options
| author | Keith Packard <keithp@keithp.com> | 2011-10-08 22:19:52 -0600 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2011-10-08 22:23:16 -0600 |
| commit | ca036c5616c3e745c0b878ed90618d4ff710c0e5 (patch) | |
| tree | e695913d8b6ad4ae65ed3d22811fcda08fedffca /src/util | |
| parent | 26d7eb7149da8c797d7e704d75f73af2d2aa52c2 (diff) | |
altos: Improve TM v1.0 apogee estimate
v1.0 boards have noisy accelerometer data caused by interactions
between RF transmission and the accelerometer measurements; this noise
generates a negative bias in the accelerometer readings. The net
effect is that the estimated speed is lower than the actual speed,
causing early an apogee estimate.
By increasing the sigma value for accelerometer data, the kalman
filter 'trusts' the acceleration data less, putting more weight on the
barometer data. This causes the estimated time of apogee to be closer
to the correct value.
This reduces the response to changes in acceleration.
This new value is applied solely to TeleMetrum v1.0 boards. v1.1
boards correct for this error, and hence can use the correct sigma
value for the accelerometer.
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src/util')
| -rw-r--r-- | src/util/make-kalman | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/util/make-kalman b/src/util/make-kalman index 397d6020..fd33bab0 100644 --- a/src/util/make-kalman +++ b/src/util/make-kalman @@ -5,11 +5,32 @@ cd $1 2> /dev/null 1>&2 SIGMA_BOTH="-M 2 -H 6 -A 2" SIGMA_BARO="-M 2 -H 6 -A 2" SIGMA_ACCEL="-M 2 -H 4 -A 4" +SIGMA_BOTH_NOISY_ACCEL="-M 2 -H 6 -A 3" + +echo '#if NOISY_ACCEL' +echo +echo '/* TeleMetrum v1.0 boards have noisy accelerometer values' +echo ' * increase the sigma value for accel data to compensate.' +echo ' * This improves the accuracy of apogee detection.' +echo ' */' +echo + +nickle kalman.5c -p AO_BOTH -c both -t 0.01 $SIGMA_BOTH_NOISY_ACCEL +nickle kalman.5c -p AO_BOTH -c both -t 0.1 $SIGMA_BOTH_NOISY_ACCEL +nickle kalman.5c -p AO_BOTH -c both -t 1 $SIGMA_BOTH_NOISY_ACCEL + +echo '#endif' +echo +echo '#ifndef AO_BOTH_K00_100' +echo nickle kalman.5c -p AO_BOTH -c both -t 0.01 $SIGMA_BOTH nickle kalman.5c -p AO_BOTH -c both -t 0.1 $SIGMA_BOTH nickle kalman.5c -p AO_BOTH -c both -t 1 $SIGMA_BOTH +echo '#endif' +echo + nickle kalman.5c -p AO_ACCEL -c accel -t 0.01 $SIGMA_ACCEL nickle kalman.5c -p AO_ACCEL -c accel -t 0.1 $SIGMA_ACCEL nickle kalman.5c -p AO_ACCEL -c accel -t 1 $SIGMA_ACCEL @@ -17,3 +38,4 @@ nickle kalman.5c -p AO_ACCEL -c accel -t 1 $SIGMA_ACCEL nickle kalman.5c -p AO_BARO -c baro -t 0.01 $SIGMA_BARO nickle kalman.5c -p AO_BARO -c baro -t 0.1 $SIGMA_BARO nickle kalman.5c -p AO_BARO -c baro -t 1 $SIGMA_BARO + |