Example due to Robert Truax in Issue #280

release/4.3a0
Frank Dellaert 2018-10-13 15:29:07 -04:00
parent 5494bee054
commit c428e30784
1 changed files with 171 additions and 0 deletions

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#include <gtsam/nonlinear/ISAM2.h>
#include <gtsam/slam/PriorFactor.h>
#include <gtsam/navigation/ImuBias.h>
#include <gtsam/navigation/ImuFactor.h>
#include <gtsam/slam/BetweenFactor.h>
#include <gtsam/inference/Symbol.h>
#include <gtsam/geometry/SimpleCamera.h>
#define GTSAM4
using namespace std;
using namespace gtsam;
/* ************************************************************************* */
std::vector<gtsam::Pose3> createPoses() {
// Create the set of ground-truth poses
std::vector<gtsam::Pose3> poses;
double radius = 30.0;
int i = 0;
double theta = 0.0;
gtsam::Point3 up(0,0,1);
gtsam::Point3 target(0,0,0);
for(; i < 80; ++i, theta += 2*M_PI/8) {
gtsam::Point3 position = gtsam::Point3(radius*cos(theta), radius*sin(theta), 0.0);
gtsam::SimpleCamera camera = gtsam::SimpleCamera::Lookat(position, target, up);
poses.push_back(camera.pose());
}
return poses;
}
/* ************************************************************************* */
/* ************************************************************************* */
int main(int argc, char* argv[]) {
// Create the set of ground-truth landmarks and poses
vector<Pose3> poses = createPoses();
// Create a factor graph
NonlinearFactorGraph newgraph;
NonlinearFactorGraph totalgraph;
// Create ISAM2 solver
ISAM2 isam, isam_full;
// Create the initial estimate to the solution
// Intentionally initialize the variables off from the ground truth
Values initialEstimate, totalEstimate, result;
// Add a prior on pose x0. This indirectly specifies where the origin is.
// 30cm std on x,y,z 0.1 rad on roll,pitch,yaw
noiseModel::Diagonal::shared_ptr noise = noiseModel::Diagonal::Sigmas(
(Vector(6) << Vector3::Constant(0.3), Vector3::Constant(0.1)).finished());
newgraph.push_back(PriorFactor<Pose3>(0, poses[0], noise));
totalgraph.push_back(PriorFactor<Pose3>(0, poses[0], noise));
// Add imu priors
int biasidx = 1000;
noiseModel::Diagonal::shared_ptr biasnoise = noiseModel::Diagonal::Sigmas((Vector(6) << 0.1, 0.1, 0.1, 0.1, 0.1, 0.1).finished());
PriorFactor<imuBias::ConstantBias> biasprior(biasidx,imuBias::ConstantBias(),biasnoise);
newgraph.push_back(biasprior);
totalgraph.push_back(biasprior);
initialEstimate.insert(biasidx, imuBias::ConstantBias());
totalEstimate.insert(biasidx, imuBias::ConstantBias());
noiseModel::Diagonal::shared_ptr velnoise = noiseModel::Diagonal::Sigmas((Vector(3) << 0.1, 0.1, 0.1).finished());
#ifdef GTSAM4
PriorFactor<Vector> velprior(100,(Vector(3) << 0, 0, 0).finished(), velnoise);
#else
PriorFactor<LieVector> velprior(100,(Vector(3) << 0, 0, 0).finished(), velnoise);
#endif
newgraph.push_back(velprior);
totalgraph.push_back(velprior);
#ifdef GTSAM4
initialEstimate.insert(100, (Vector(3) << 0, 0, 0).finished());
totalEstimate.insert(100, (Vector(3) << 0, 0, 0).finished());
#else
initialEstimate.insert(100, LieVector((Vector(3) << 0, 0, 0).finished()));
totalEstimate.insert(100, LieVector((Vector(3) << 0, 0, 0).finished()));
#endif
Matrix3 I;
I << 1, 0, 0, 0, 1, 0, 0, 0, 1;
Matrix3 accCov = I*0.1;
Matrix3 gyroCov = I*0.1;
Matrix3 intCov = I*0.1;
bool secOrder = false;
#ifdef GTSAM4
// IMU preintegrator
PreintegratedImuMeasurements accum(PreintegrationParams::MakeSharedD());
accum.params()->setAccelerometerCovariance(accCov);
accum.params()->setGyroscopeCovariance(gyroCov);
accum.params()->setIntegrationCovariance(intCov);
accum.params()->setUse2ndOrderCoriolis(secOrder);
accum.params()->setOmegaCoriolis(Vector3(0, 0, 0));
#else
ImuFactor::PreintegratedMeasurements accum(imuBias::ConstantBias(), accCov, gyroCov, intCov, secOrder);
#endif
// Simulate poses and imu measurements, adding them to the factor graph
for (size_t i = 0; i < poses.size(); ++i) {
#ifdef GTSAM4
Pose3 delta(Rot3::Rodrigues(-0.1, 0.2, 0.25), Point3(0.05, -0.10, 0.20));
#else
Pose3 delta(Rot3::ypr(-0.1, 0.2, 0.25), Point3(0.05, -0.10, 0.20));
#endif
if (i == 0) { // First time add two poses
initialEstimate.insert(0, poses[0].compose(delta));
initialEstimate.insert(1, poses[1].compose(delta));
totalEstimate.insert(0, poses[0].compose(delta));
totalEstimate.insert(1, poses[1].compose(delta));
} else if (i >= 2) { // Add more poses as necessary
initialEstimate.insert(i, poses[i].compose(delta));
totalEstimate.insert(i, poses[i].compose(delta));
}
if (i > 0) {
// Add Bias variables periodically
if (i % 5 == 0) {
biasidx++;
Symbol b1 = biasidx-1;
Symbol b2 = biasidx;
imuBias::ConstantBias basebias = imuBias::ConstantBias();
Vector6 covvec;
covvec << 0.1, 0.1, 0.1, 0.1, 0.1, 0.1;
noiseModel::Diagonal::shared_ptr cov = noiseModel::Diagonal::Variances(covvec);
Vector6 zerovec;
zerovec << 0, 0, 0, 0, 0, 0;
BetweenFactor<imuBias::ConstantBias>::shared_ptr f(new BetweenFactor<imuBias::ConstantBias>(b1, b2, imuBias::ConstantBias(), cov));
newgraph.add(f);
totalgraph.add(f);
initialEstimate.insert(biasidx, imuBias::ConstantBias());
totalEstimate.insert(biasidx, imuBias::ConstantBias());
}
// Add Imu Factor
accum.integrateMeasurement((Vector(3) << 0.0, 0.0, -9.8).finished(), (Vector(3) << 0, 0, 0).finished(), 0.5);
#ifdef GTSAM4
ImuFactor imufac(i-1, 100+i-1,i,100+i, biasidx, accum);
#else
ImuFactor imufac(i-1, 100+i-1,i,100+i, biasidx, accum, (Vector(3) << 0.0, 0.0, -9.8).finished(), (Vector(3) << 0.0, 0.0, 0.0).finished());
#endif
newgraph.add(imufac);
totalgraph.add(imufac);
#ifdef GTSAM4
initialEstimate.insert(100+i, (Vector(3) << 0.0, 0.0, -9.8).finished()); // insert new velocity
totalEstimate.insert(100+i, (Vector(3) << 0.0, 0.0, -9.8).finished()); // insert new velocity
#else
initialEstimate.insert(100+i, LieVector((Vector(3) << 0.0, 0.0, -9.8).finished())); // insert new velocity
totalEstimate.insert(100+i, LieVector((Vector(3) << 0.0, 0.0, -9.8).finished())); // insert new velocity
#endif
accum.resetIntegration();
}
// Batch solution
isam_full = ISAM2();
isam_full.update(totalgraph, totalEstimate);
result = isam_full.calculateEstimate();
// Incremental solution
isam.update(newgraph, initialEstimate);
result = isam.calculateEstimate();
newgraph = NonlinearFactorGraph();
initialEstimate.clear();
}
return 0;
}
/* ************************************************************************* */