gtsam/gtsam_unstable/dynamics/DynamicsPriors.h

92 lines
2.7 KiB
C++

/**
* @file DynamicsPriors.h
*
* @brief Priors to be used with dynamic systems (Specifically PoseRTV)
*
* @date Nov 22, 2011
* @author Alex Cunningham
*/
#pragma once
#include <gtsam_unstable/dynamics/PoseRTV.h>
#include <gtsam_unstable/slam/PartialPriorFactor.h>
#include <cassert>
namespace gtsam {
// Indices of relevant variables in the PoseRTV tangent vector:
// [ rx ry rz tx ty tz vx vy vz ]
static const size_t kRollIndex = 0;
static const size_t kPitchIndex = 1;
static const size_t kHeightIndex = 5;
static const size_t kVelocityZIndex = 8;
static const std::vector<size_t> kVelocityIndices = { 6, 7, 8 };
/**
* Forces the value of the height (z) in a PoseRTV to a specific value.
* Dim: 1
*/
struct DHeightPrior : public gtsam::PartialPriorFactor<PoseRTV> {
typedef gtsam::PartialPriorFactor<PoseRTV> Base;
DHeightPrior(Key key, double height, const gtsam::SharedNoiseModel& model)
: Base(key, kHeightIndex, height, model) {}
};
/**
* Forces the roll to a particular value - useful for flying robots
* Implied value is zero
* Dim: 1
*/
struct DRollPrior : public gtsam::PartialPriorFactor<PoseRTV> {
typedef gtsam::PartialPriorFactor<PoseRTV> Base;
/** allows for explicit roll parameterization - uses canonical coordinate */
DRollPrior(Key key, double wx, const gtsam::SharedNoiseModel& model)
: Base(key, kRollIndex, wx, model) { }
/** Forces roll to zero */
DRollPrior(Key key, const gtsam::SharedNoiseModel& model)
: Base(key, kRollIndex, 0.0, model) { }
};
/**
* Constrains the full velocity of a state to a particular value
* Useful for enforcing a stationary state
* Dim: 3
*/
struct VelocityPrior : public gtsam::PartialPriorFactor<PoseRTV> {
typedef gtsam::PartialPriorFactor<PoseRTV> Base;
VelocityPrior(Key key, const gtsam::Vector& vel, const gtsam::SharedNoiseModel& model)
: Base(key, kVelocityIndices, vel, model) {}
};
/**
* Ground constraint: forces the robot to be upright (no roll, pitch), a fixed height, and no
* velocity in z direction
* Dim: 4
*/
struct DGroundConstraint : public gtsam::PartialPriorFactor<PoseRTV> {
typedef gtsam::PartialPriorFactor<PoseRTV> Base;
/**
* Primary constructor allows for variable height of the "floor"
*/
DGroundConstraint(Key key, double height, const gtsam::SharedNoiseModel& model)
: Base(key, { kHeightIndex, kVelocityZIndex, kRollIndex, kPitchIndex },
Vector::Unit(4, 0)*height, model) {}
/**
* Fully specify vector - use only for debugging
*/
DGroundConstraint(Key key, const Vector& constraint, const gtsam::SharedNoiseModel& model)
: Base(key, { kHeightIndex, kVelocityZIndex, kRollIndex, kPitchIndex }, constraint, model) {
assert(constraint.size() == 4);
}
};
} // \namespace gtsam