sensor_fusion.hpp File Reference

Constellation tracker sensor fusion. More...

#include "xrt/xrt_config_build.h"
#include "os/os_threading.h"
#include "tracking/t_constellation.h"
#include "constellation/t_constellation_tracker.h"
#include "math/m_relation_history.h"
#include "imu_preintegration.hpp"
#include <array>
#include <atomic>
#include <ceres/context.h>
#include <cstddef>
#include <cstring>
#include <memory>
#include <optional>
#include <string>
#include <type_traits>
#include <vector>

Include dependency graph for sensor_fusion.hpp:

Go to the source code of this file.

Data Structures
struct	xrt::tracking::constellation::optimizer::sensor_fusion::DeviceObservation
struct	xrt::tracking::constellation::optimizer::sensor_fusion::Keyframe
struct	xrt::tracking::constellation::optimizer::sensor_fusion::RingImuSample
	One IMU sample as it sits in Device::imu_samples. More...
struct	xrt::tracking::constellation::optimizer::sensor_fusion::DevicePreintegration
	Stores state for a single preintegration residual for a device. More...
struct	xrt::tracking::constellation::optimizer::sensor_fusion::DeviceImuCalibration
	The IMU intrinsics the rig calibration happened to solve for, as the fusion takes them in as a seed. More...
struct	xrt::tracking::constellation::optimizer::sensor_fusion::DeviceSolveState
struct	xrt::tracking::constellation::optimizer::sensor_fusion::Device
struct	xrt::tracking::constellation::optimizer::sensor_fusion::CameraDescription
struct	xrt::tracking::constellation::optimizer::sensor_fusion::SolvedDeviceKeyframe
	A device's solved state at one keyframe. More...
struct	xrt::tracking::constellation::optimizer::sensor_fusion::SnapshotObservation
	One camera's view of one device at one keyframe. More...
struct	xrt::tracking::constellation::optimizer::sensor_fusion::SnapshotKeyframe
struct	xrt::tracking::constellation::optimizer::sensor_fusion::SnapshotDevice
struct	xrt::tracking::constellation::optimizer::sensor_fusion::SolveSnapshot
	One solve, whole: what went in, what came out, and how the solver got there. More...
struct	xrt::tracking::constellation::optimizer::sensor_fusion::SensorFusion

Enumerations
enum class	xrt::tracking::constellation::optimizer::sensor_fusion::DevicePreintegrationState { Dirty , Empty , Integrated }

Variables
static constexpr uint32_t	xrt::tracking::constellation::optimizer::sensor_fusion::kSlidingWindowSize = 3
	How many keyframes to keep in our sliding window.
static constexpr uint32_t	xrt::tracking::constellation::optimizer::sensor_fusion::kImuBufferSize = 5000
	The number of IMU samples to keep in our ring buffer.
static constexpr uint32_t	xrt::tracking::constellation::optimizer::sensor_fusion::kMaxImuSamplesPerKeyframe = 512
	The most IMU samples we ever expect to find between two keyframes.
static constexpr uint32_t	xrt::tracking::constellation::optimizer::sensor_fusion::kKeyframeSealLagKeyframes = 2
	How many newer keyframes have to pile up before a keyframe gets sealed and marginalized.
static constexpr uint32_t	xrt::tracking::constellation::optimizer::sensor_fusion::kMaxQueuedCameraSamples = 32
	How many camera samples may be queued for the fusion thread before new ones start being dropped.

Detailed Description

Constellation tracker sensor fusion.

Author

Beyley Cardellio ep1cm.nosp@m.1n10.nosp@m.n123@.nosp@m.gmai.nosp@m.l.com

Enumeration Type Documentation

DevicePreintegrationState

enum class xrt::tracking::constellation::optimizer::sensor_fusion::DevicePreintegrationState

strong

Enumerator
Dirty	Needs to be recomputed.
Empty	Does not refer to any real pre-integration. This term contributes nothing and can be skipped.
Integrated	This preintegration is complete and will never change.

Variable Documentation

kImuBufferSize

constexpr uint32_t xrt::tracking::constellation::optimizer::sensor_fusion::kImuBufferSize = 5000

staticconstexpr

The number of IMU samples to keep in our ring buffer.

kKeyframeSealLagKeyframes

constexpr uint32_t xrt::tracking::constellation::optimizer::sensor_fusion::kKeyframeSealLagKeyframes = 2

staticconstexpr

How many newer keyframes have to pile up before a keyframe gets sealed and marginalized.

kMaxImuSamplesPerKeyframe

constexpr uint32_t xrt::tracking::constellation::optimizer::sensor_fusion::kMaxImuSamplesPerKeyframe = 512

staticconstexpr

The most IMU samples we ever expect to find between two keyframes.

At a 1KHz IMU and a keyframe every few tens of milliseconds the real count is well under a hundred, so this is generous headroom rather than a tight bound. Sizing the staging buffer off this instead of kImuBufferSize keeps it small enough to sit on the stack.

kMaxQueuedCameraSamples

constexpr uint32_t xrt::tracking::constellation::optimizer::sensor_fusion::kMaxQueuedCameraSamples = 32

staticconstexpr

How many camera samples may be queued for the fusion thread before new ones start being dropped.

The fusion thread drains the whole queue every pass, so if this grows past even a handful, the thread has stalled a lot and we should just warn and start dropping them to not use an ever-increasing amount of RAM.

kSlidingWindowSize

constexpr uint32_t xrt::tracking::constellation::optimizer::sensor_fusion::kSlidingWindowSize = 3

staticconstexpr

How many keyframes to keep in our sliding window.