AP_NavEKF3: Retune and fix delta velocity bias state variance protection

This commit is contained in:
Paul Riseborough 2023-04-28 18:29:44 +10:00 committed by Andrew Tridgell
parent 06029854f1
commit df737449e0
1 changed files with 7 additions and 7 deletions

View File

@ -1912,12 +1912,11 @@ void NavEKF3_core::ConstrainVariances()
zeroRows(P,10,12);
}
const ftype minStateVarTarget = 1E-11;
const ftype minSafeStateVar = 1E-9;
if (!inhibitDelVelBiasStates) {
// Find the maximum delta velocity bias state variance and request a covariance reset if any variance is below the safe minimum
const ftype minSafeStateVar = minStateVarTarget * 0.1f;
ftype maxStateVar = minSafeStateVar;
ftype maxStateVar = 0.0F;
bool resetRequired = false;
for (uint8_t stateIndex=13; stateIndex<=15; stateIndex++) {
if (P[stateIndex][stateIndex] > maxStateVar) {
@ -1929,7 +1928,7 @@ void NavEKF3_core::ConstrainVariances()
// To ensure stability of the covariance matrix operations, the ratio of a max and min variance must
// not exceed 100 and the minimum variance must not fall below the target minimum
ftype minAllowedStateVar = fmaxF(0.01f * maxStateVar, minStateVarTarget);
ftype minAllowedStateVar = fmaxF(0.01f * maxStateVar, minSafeStateVar);
for (uint8_t stateIndex=13; stateIndex<=15; stateIndex++) {
P[stateIndex][stateIndex] = constrain_ftype(P[stateIndex][stateIndex], minAllowedStateVar, sq(10.0f * dtEkfAvg));
}
@ -1944,18 +1943,19 @@ void NavEKF3_core::ConstrainVariances()
// reset all delta velocity bias covariances
zeroCols(P,13,15);
zeroRows(P,13,15);
// restore all delta velocity bias variances
// restore all delta velocity bias variances to a margin above the minimum safe value
for (uint8_t i=0; i<=2; i++) {
P[i+13][i+13] = delVelBiasVar[i];
P[i+13][i+13] = MAX(delVelBiasVar[i], minSafeStateVar * 10.0F);
}
}
} else {
zeroCols(P,13,15);
zeroRows(P,13,15);
// set all delta velocity bias variances to a margin above the minimum safe value
for (uint8_t i=0; i<=2; i++) {
const uint8_t stateIndex = i + 13;
P[stateIndex][stateIndex] = fmaxF(P[stateIndex][stateIndex], minStateVarTarget);
P[stateIndex][stateIndex] = fmaxF(P[stateIndex][stateIndex], minSafeStateVar * 10.0F);
}
}