gtsam/gtsam/navigation/ImuFactor.cpp

259 lines
10 KiB
C++

/* ----------------------------------------------------------------------------
* GTSAM Copyright 2010, Georgia Tech Research Corporation,
* Atlanta, Georgia 30332-0415
* All Rights Reserved
* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
* See LICENSE for the license information
* -------------------------------------------------------------------------- */
/**
* @file ImuFactor.cpp
* @author Luca Carlone
* @author Stephen Williams
* @author Richard Roberts
* @author Vadim Indelman
* @author David Jensen
* @author Frank Dellaert
**/
#include <gtsam/navigation/ImuFactor.h>
/* External or standard includes */
#include <ostream>
namespace gtsam {
using namespace std;
//------------------------------------------------------------------------------
// Inner class PreintegratedImuMeasurements
//------------------------------------------------------------------------------
void PreintegratedImuMeasurements::print(const string& s) const {
PreintegrationType::print(s);
cout << " preintMeasCov \n[" << preintMeasCov_ << "]" << endl;
}
//------------------------------------------------------------------------------
bool PreintegratedImuMeasurements::equals(
const PreintegratedImuMeasurements& other, double tol) const {
return PreintegrationType::equals(other, tol)
&& equal_with_abs_tol(preintMeasCov_, other.preintMeasCov_, tol);
}
//------------------------------------------------------------------------------
void PreintegratedImuMeasurements::resetIntegration() {
PreintegrationType::resetIntegration();
preintMeasCov_.setZero();
}
//------------------------------------------------------------------------------
void PreintegratedImuMeasurements::integrateMeasurement(
const Vector3& measuredAcc, const Vector3& measuredOmega, double dt) {
if (dt <= 0) {
throw std::runtime_error(
"PreintegratedImuMeasurements::integrateMeasurement: dt <=0");
}
// Update preintegrated measurements (also get Jacobian)
Matrix9 A; // overall Jacobian wrt preintegrated measurements (df/dx)
Matrix93 B, C; // Jacobian of state wrpt accel bias and omega bias respectively.
PreintegrationType::update(measuredAcc, measuredOmega, dt, &A, &B, &C);
// first order covariance propagation:
// as in [2] we consider a first order propagation that can be seen as a
// prediction phase in EKF
// propagate uncertainty
// TODO(frank): use noiseModel routine so we can have arbitrary noise models.
const Matrix3& aCov = p().accelerometerCovariance;
const Matrix3& wCov = p().gyroscopeCovariance;
const Matrix3& iCov = p().integrationCovariance;
// (1/dt) allows to pass from continuous time noise to discrete time noise
// Update the uncertainty on the state (matrix A in [4]).
preintMeasCov_ = A * preintMeasCov_ * A.transpose();
// These 2 updates account for uncertainty on the IMU measurement (matrix B in [4]).
preintMeasCov_.noalias() += B * (aCov / dt) * B.transpose();
preintMeasCov_.noalias() += C * (wCov / dt) * C.transpose();
// NOTE(frank): (Gi*dt)*(C/dt)*(Gi'*dt), with Gi << Z_3x3, I_3x3, Z_3x3 (9x3 matrix)
preintMeasCov_.block<3, 3>(3, 3).noalias() += iCov * dt;
}
//------------------------------------------------------------------------------
void PreintegratedImuMeasurements::integrateMeasurements(
const Matrix& measuredAccs, const Matrix& measuredOmegas,
const Matrix& dts) {
assert(
measuredAccs.rows() == 3 && measuredOmegas.rows() == 3 && dts.rows() == 1);
assert(dts.cols() >= 1);
assert(measuredAccs.cols() == dts.cols());
assert(measuredOmegas.cols() == dts.cols());
size_t n = static_cast<size_t>(dts.cols());
for (size_t j = 0; j < n; j++) {
integrateMeasurement(measuredAccs.col(j), measuredOmegas.col(j), dts(0, j));
}
}
//------------------------------------------------------------------------------
#ifdef GTSAM_TANGENT_PREINTEGRATION
void PreintegratedImuMeasurements::mergeWith(const PreintegratedImuMeasurements& pim12, //
Matrix9* H1, Matrix9* H2) {
PreintegrationType::mergeWith(pim12, H1, H2);
// NOTE(gareth): Temporary P is needed as of Eigen 3.3
const Matrix9 P = *H1 * preintMeasCov_ * H1->transpose();
preintMeasCov_ = P + *H2 * pim12.preintMeasCov_ * H2->transpose();
}
#endif
//------------------------------------------------------------------------------
// ImuFactor methods
//------------------------------------------------------------------------------
ImuFactor::ImuFactor(Key pose_i, Key vel_i, Key pose_j, Key vel_j, Key bias,
const PreintegratedImuMeasurements& pim) :
Base(noiseModel::Gaussian::Covariance(pim.preintMeasCov_), pose_i, vel_i,
pose_j, vel_j, bias), _PIM_(pim) {
}
//------------------------------------------------------------------------------
NonlinearFactor::shared_ptr ImuFactor::clone() const {
return boost::static_pointer_cast<NonlinearFactor>(
NonlinearFactor::shared_ptr(new This(*this)));
}
//------------------------------------------------------------------------------
std::ostream& operator<<(std::ostream& os, const ImuFactor& f) {
f._PIM_.print("preintegrated measurements:\n");
os << " noise model sigmas: " << f.noiseModel_->sigmas().transpose();
return os;
}
//------------------------------------------------------------------------------
void ImuFactor::print(const string& s, const KeyFormatter& keyFormatter) const {
cout << (s.empty() ? s : s + "\n") << "ImuFactor(" << keyFormatter(this->key<1>())
<< "," << keyFormatter(this->key<2>()) << "," << keyFormatter(this->key<3>())
<< "," << keyFormatter(this->key<4>()) << "," << keyFormatter(this->key<5>())
<< ")\n";
cout << *this << endl;
}
//------------------------------------------------------------------------------
bool ImuFactor::equals(const NonlinearFactor& other, double tol) const {
const This *e = dynamic_cast<const This*>(&other);
const bool base = Base::equals(*e, tol);
const bool pim = _PIM_.equals(e->_PIM_, tol);
return e != nullptr && base && pim;
}
//------------------------------------------------------------------------------
Vector ImuFactor::evaluateError(const Pose3& pose_i, const Vector3& vel_i,
const Pose3& pose_j, const Vector3& vel_j,
const imuBias::ConstantBias& bias_i, boost::optional<Matrix&> H1,
boost::optional<Matrix&> H2, boost::optional<Matrix&> H3,
boost::optional<Matrix&> H4, boost::optional<Matrix&> H5) const {
return _PIM_.computeErrorAndJacobians(pose_i, vel_i, pose_j, vel_j, bias_i,
H1, H2, H3, H4, H5);
}
//------------------------------------------------------------------------------
#ifdef GTSAM_TANGENT_PREINTEGRATION
PreintegratedImuMeasurements ImuFactor::Merge(
const PreintegratedImuMeasurements& pim01,
const PreintegratedImuMeasurements& pim12) {
if (!pim01.matchesParamsWith(pim12))
throw std::domain_error(
"Cannot merge PreintegratedImuMeasurements with different params");
if (pim01.params()->body_P_sensor)
throw std::domain_error(
"Cannot merge PreintegratedImuMeasurements with sensor pose yet");
// the bias for the merged factor will be the bias from 01
PreintegratedImuMeasurements pim02 = pim01;
Matrix9 H1, H2;
pim02.mergeWith(pim12, &H1, &H2);
return pim02;
}
//------------------------------------------------------------------------------
ImuFactor::shared_ptr ImuFactor::Merge(const shared_ptr& f01,
const shared_ptr& f12) {
// IMU bias keys must be the same.
if (f01->key<5>() != f12->key<5>())
throw std::domain_error("ImuFactor::Merge: IMU bias keys must be the same");
// expect intermediate pose, velocity keys to matchup.
if (f01->key<3>() != f12->key<1>() || f01->key<4>() != f12->key<2>())
throw std::domain_error(
"ImuFactor::Merge: intermediate pose, velocity keys need to match up");
// return new factor
auto pim02 =
Merge(f01->preintegratedMeasurements(), f12->preintegratedMeasurements());
return boost::make_shared<ImuFactor>(f01->key<1>(), // P0
f01->key<2>(), // V0
f12->key<3>(), // P2
f12->key<4>(), // V2
f01->key<5>(), // B
pim02);
}
#endif
//------------------------------------------------------------------------------
// ImuFactor2 methods
//------------------------------------------------------------------------------
ImuFactor2::ImuFactor2(Key state_i, Key state_j, Key bias,
const PreintegratedImuMeasurements& pim) :
Base(noiseModel::Gaussian::Covariance(pim.preintMeasCov_), state_i, state_j,
bias), _PIM_(pim) {
}
//------------------------------------------------------------------------------
NonlinearFactor::shared_ptr ImuFactor2::clone() const {
return boost::static_pointer_cast<NonlinearFactor>(
NonlinearFactor::shared_ptr(new This(*this)));
}
//------------------------------------------------------------------------------
std::ostream& operator<<(std::ostream& os, const ImuFactor2& f) {
f._PIM_.print("preintegrated measurements:\n");
os << " noise model sigmas: " << f.noiseModel_->sigmas().transpose();
return os;
}
//------------------------------------------------------------------------------
void ImuFactor2::print(const string& s,
const KeyFormatter& keyFormatter) const {
cout << (s.empty() ? s : s + "\n") << "ImuFactor2("
<< keyFormatter(this->key<1>()) << "," << keyFormatter(this->key<2>()) << ","
<< keyFormatter(this->key<3>()) << ")\n";
cout << *this << endl;
}
//------------------------------------------------------------------------------
bool ImuFactor2::equals(const NonlinearFactor& other, double tol) const {
const This *e = dynamic_cast<const This*>(&other);
const bool base = Base::equals(*e, tol);
const bool pim = _PIM_.equals(e->_PIM_, tol);
return e != nullptr && base && pim;
}
//------------------------------------------------------------------------------
Vector ImuFactor2::evaluateError(const NavState& state_i,
const NavState& state_j,
const imuBias::ConstantBias& bias_i, //
boost::optional<Matrix&> H1, boost::optional<Matrix&> H2,
boost::optional<Matrix&> H3) const {
return _PIM_.computeError(state_i, state_j, bias_i, H1, H2, H3);
}
//------------------------------------------------------------------------------
}
// namespace gtsam