Class CObservation2DRangeScan

Inheritance Relationships

Base Type

Class Documentation

class CObservation2DRangeScan : public mrpt::obs::CObservation

A “CObservation”-derived class that represents a 2D range scan measurement (typically from a laser scanner). The data structures are generic enough to hold a wide variety of 2D scanners and “3D” planar rotating 2D lasers.

These are the most important data fields:

  • Scan ranges: A vector of float values with all the range measurements [meters]. Access via CObservation2DRangeScan::getScanRange() and CObservation2DRangeScan::setScanRange().

  • Range validity: A vector (of identical size to scan

Scan data

float aperture = {M_PIf}

The “aperture” or field-of-view of the range finder, in radians (typically M_PI = 180 degrees).

bool rightToLeft = {true}

The scanning direction: true=counterclockwise; false=clockwise

float maxRange = {80.0f}

The maximum range allowed by the device, in meters (e.g. 80m, 50m,…)

mrpt::poses::CPose3D sensorPose

The 6D pose of the sensor on the robot at the moment of starting the scan.

float stdError = {0.01f}

The “sigma” error of the device in meters, used while inserting the scan in an occupancy grid.

float beamAperture = {0}

The aperture of each beam, in radians, used to insert “thick” rays in the occupancy grid.

double deltaPitch = {0}

If the laser gathers data by sweeping in the pitch/elevation angle, this holds the increment in “pitch” (=-“elevation”) between the beginning and the end of the scan (the sensorPose member stands for the pose at the beginning of the scan).

float sweepDuration = {.0f}

Time that takes one LIDAR rotation (in seconds). 0=means, not available. This is used to compute per-point timestamps

void resizeScan(size_t len)

Resizes all data vectors to allocate a given number of scan rays

void resizeScanAndAssign(size_t len, const float rangeVal, const bool rangeValidity, const int32_t rangeIntensity = 0)

Resizes all data vectors to allocate a given number of scan rays and assign default values.

size_t getScanSize() const

Get number of scan rays

const float &getScanRange(size_t i) const

The range values of the scan, in meters. Must have same length than validRange

float &getScanRange(size_t i)
void setScanRange(size_t i, const float val)
const int32_t &getScanIntensity(size_t i) const

The intensity values of the scan. If available, must have same length than validRange

int32_t &getScanIntensity(size_t i)
void setScanIntensity(size_t i, const int val)
bool getScanRangeValidity(size_t i) const

It’s false (=0) on no reflected rays, referenced to elements in scan

void setScanRangeValidity(size_t i, const bool val)
float getScanRelativeTimestamp(size_t idx) const
float getScanAngle(size_t idx) const

Returns the computed direction (relative heading in radians, with 0=forward) of the given ray index, following the following formula: 

float Ang = -0.5f * aperture;
float dA = aperture / (m_scan.size() - 1);
if (!rightToLeft)
{
 Ang = -Ang;
 dA = -dA;
}
return Ang + dA * idx;

\params[in] idx Index of the ray, from 0 to size()-1.

Note

(New in MRPT 2.3.1)

void getScanProperties(T2DScanProperties &p) const

Fill out a T2DScanProperties structure with the parameters of this scan

Cached points map

mutable mrpt::containers::NonCopiableData<std::recursive_mutex> m_cachedMapMtx

A points map, build only under demand by the methods getAuxPointsMap() and buildAuxPointsMap(). It’s a generic smart pointer to avoid depending here in the library mrpt-obs on classes on other libraries.

mutable mrpt::maps::CMetricMap::Ptr m_cachedMap
template<class POINTSMAP>
inline const POINTSMAP *getAuxPointsMap() const

Returns the cached points map representation of the scan, if already build with buildAuxPointsMap(), or nullptr otherwise. Usage: 

   mrpt::maps::CPointsMap *map =
obs->getAuxPointsMap<mrpt::maps::CPointsMap>();

See also

buildAuxPointsMap

template<class POINTSMAP>
inline const POINTSMAP *buildAuxPointsMap(const void *options = nullptr) const

Returns a cached points map representing this laser scan, building it upon the first call.

See also

getAuxPointsMap

Parameters:

options – Can be nullptr to use default point maps’ insertion options, or a pointer to a “CPointsMap::TInsertionOptions” structure to override some params. Usage: 

   mrpt::maps::CPointsMap *map =
obs->buildAuxPointsMap<mrpt::maps::CPointsMap>(&options or nullptr);

void internal_buildAuxPointsMap(const void *options = nullptr) const

Internal method, used from buildAuxPointsMap()

Public Types

using TListExclusionAreas = std::vector<mrpt::math::CPolygon>

Used in filterByExclusionAreas

using TListExclusionAreasWithRanges = std::vector<std::pair<mrpt::math::CPolygon, std::pair<double, double>>>

Used in filterByExclusionAreas

Public Functions

CObservation2DRangeScan() = default

Default constructor

void loadFromVectors(size_t nRays, const float *scanRanges, const char *scanValidity)
bool isPlanarScan(const double tolerance = 0) const

Return true if the laser scanner is “horizontal”, so it has an absolute value of “pitch” and “roll” less or equal to the given tolerance (in rads, default=0) (with the normal vector either upwards or downwards).

bool hasIntensity() const

Return true if scan has intensity

void setScanHasIntensity(bool setHasIntensityFlag)

Marks this scan as having or not intensity data.

inline virtual void getSensorPose(mrpt::poses::CPose3D &out_sensorPose) const override

A general method to retrieve the sensor pose on the robot. Note that most sensors will return a full (6D) CPose3D, but see the derived classes for more details or special cases.

See also

setSensorPose

inline virtual void setSensorPose(const mrpt::poses::CPose3D &newSensorPose) override

A general method to change the sensor pose on the robot. Note that most sensors will use the full (6D) CPose3D, but see the derived classes for more details or special cases.

See also

getSensorPose

virtual void getDescriptionAsText(std::ostream &o) const override

Build a detailed, multi-line textual description of the observation contents and dump it to the output stream.

Note

If overried by derived classes, call base CObservation::getDescriptionAsText() first to show common information.

Note

This is the text that appears in RawLogViewer when selecting an object in the dataset

void truncateByDistanceAndAngle(float min_distance, float max_angle, float min_height = 0, float max_height = 0, float h = 0)

A general method to truncate the scan by defining a minimum valid distance and a maximum valid angle as well as minimum and maximum heights (NOTE: the laser z-coordinate must be provided).

void filterByExclusionAreas(const TListExclusionAreas &areas)

Mark as invalid sensed points that fall within any of a set of “exclusion areas”, given in coordinates relative to the vehicle (taking into account “sensorPose”).

See also

C2DRangeFinderAbstract::loadExclusionAreas

void filterByExclusionAreas(const TListExclusionAreasWithRanges &areas)

Mark as invalid sensed points that fall within any of a set of “exclusion areas”, given in coordinates relative to the vehicle (taking into account “sensorPose”), AND such as the Z coordinate of the point falls in the range [min,max] associated to each exclusion polygon.

See also

C2DRangeFinderAbstract::loadExclusionAreas

void filterByExclusionAngles(const std::vector<std::pair<double, double>> &angles)

Mark as invalid the ranges in any of a given set of “forbiden angle

ranges”, given as pairs<min_angle,max_angle>.

See also

C2DRangeFinderAbstract::loadExclusionAreas

inline virtual bool exportTxtSupported() const override

Must return true if the class is exportable to TXT/CSV files, in which case the other virtual methods in this group must be redefined too.

virtual std::string exportTxtHeader() const override

Returns the description of the data columns. Timestamp is automatically included as the first column, do not list it. See example implementations if interested in enabling this in custom CObservation classes. Do not include newlines.

virtual std::string exportTxtDataRow() const override

Returns one row of data with the data stored in this particular object. Do not include newlines.