DemoIMU Class Reference

Plot raw IMU readings on top of video. More...

Inheritance diagram for DemoIMU:

Collaboration diagram for DemoIMU:

Public Member Functions
	DemoIMU (std::string const &instance)
	Constructor.
virtual	~DemoIMU ()
	Virtual destructor for safe inheritance.
virtual void	process (jevois::InputFrame &&inframe, jevois::OutputFrame &&outframe) override
	Processing function.
virtual void	process (jevois::InputFrame &&inframe, jevois::GUIhelper &helper) override
	Processing function with GUI output.
Public Member Functions inherited from jevois::Module
	Module (std::string const &instance)
virtual	~Module ()
virtual void	process (InputFrame &&inframe)
virtual void	sendSerial (std::string const &str)
virtual void	parseSerial (std::string const &str, std::shared_ptr< UserInterface > s)
virtual void	supportedCommands (std::ostream &os)
Public Member Functions inherited from jevois::Component
	Component (std::string const &instance)
virtual	~Component ()
std::shared_ptr< Comp >	addSubComponent (std::string const &instance, Args &&...args)
void	removeSubComponent (std::shared_ptr< Comp > &component)
void	removeSubComponent (std::string const &instance, bool warnIfNotFound=true)
std::shared_ptr< Comp >	getSubComponent (std::string const &instance) const
bool	isTopLevel () const
bool	initialized () const
std::string const &	className () const
std::string const &	instanceName () const
std::vector< std::string >	setParamVal (std::string const &paramdescriptor, T const &val)
void	setParamValUnique (std::string const &paramdescriptor, T const &val)
std::vector< std::pair< std::string, T > >	getParamVal (std::string const &paramdescriptor) const
T	getParamValUnique (std::string const &paramdescriptor) const
std::vector< std::string >	setParamString (std::string const &paramdescriptor, std::string const &val)
void	setParamStringUnique (std::string const &paramdescriptor, std::string const &val)
std::vector< std::pair< std::string, std::string > >	getParamString (std::string const &paramdescriptor) const
std::string	getParamStringUnique (std::string const &paramdescriptor) const
void	freezeParam (std::string const &paramdescriptor, bool doit)
void	freezeAllParams (bool doit)
std::string	descriptor () const
void	setParamsFromFile (std::string const &filename)
std::istream &	setParamsFromStream (std::istream &is, std::string const &absfile)
virtual void	paramInfo (std::shared_ptr< UserInterface > s, std::map< std::string, std::string > &categs, bool skipFrozen, std::string const &cname="", std::string const &pfx="")
void	foreachParam (std::function< void(std::string const &compname, ParameterBase *p)> func, std::string const &cname="")
std::shared_ptr< DynamicParameter< T > >	addDynamicParameter (std::string const &name, std::string const &description, T const &defaultValue, ParameterCategory const &category)
std::shared_ptr< DynamicParameter< T > >	addDynamicParameter (std::string const &name, std::string const &description, T const &defaultValue, ValidValuesSpec< T > const &validValuesSpec, ParameterCategory const &category)
void	setDynamicParameterCallback (std::string const &name, std::function< void(T const &)> cb, bool callnow=true)
void	removeDynamicParameter (std::string const &name, bool throw_if_not_found=true)
void	setPath (std::string const &path)
std::filesystem::path	absolutePath (std::filesystem::path const &path="")
std::shared_ptr< Comp >	addSubComponent (std::string const &instance, Args &&...args)
void	removeSubComponent (std::shared_ptr< Comp > &component)
void	removeSubComponent (std::string const &instance, bool warnIfNotFound=true)
std::shared_ptr< Comp >	getSubComponent (std::string const &instance) const
bool	isTopLevel () const
bool	initialized () const
std::string const &	className () const
std::string const &	instanceName () const
std::vector< std::string >	setParamVal (std::string const &paramdescriptor, T const &val)
void	setParamValUnique (std::string const &paramdescriptor, T const &val)
std::vector< std::pair< std::string, T > >	getParamVal (std::string const &paramdescriptor) const
T	getParamValUnique (std::string const &paramdescriptor) const
std::vector< std::string >	setParamString (std::string const &paramdescriptor, std::string const &val)
void	setParamStringUnique (std::string const &paramdescriptor, std::string const &val)
std::vector< std::pair< std::string, std::string > >	getParamString (std::string const &paramdescriptor) const
std::string	getParamStringUnique (std::string const &paramdescriptor) const
void	freezeParam (std::string const &paramdescriptor, bool doit)
void	freezeAllParams (bool doit)
std::string	descriptor () const
void	setParamsFromFile (std::string const &filename)
std::istream &	setParamsFromStream (std::istream &is, std::string const &absfile)
virtual void	paramInfo (std::shared_ptr< UserInterface > s, std::map< std::string, std::string > &categs, bool skipFrozen, std::string const &cname="", std::string const &pfx="")
void	foreachParam (std::function< void(std::string const &compname, ParameterBase *p)> func, std::string const &cname="")
std::shared_ptr< DynamicParameter< T > >	addDynamicParameter (std::string const &name, std::string const &description, T const &defaultValue, ParameterCategory const &category)
std::shared_ptr< DynamicParameter< T > >	addDynamicParameter (std::string const &name, std::string const &description, T const &defaultValue, ValidValuesSpec< T > const &validValuesSpec, ParameterCategory const &category)
void	setDynamicParameterCallback (std::string const &name, std::function< void(T const &)> cb, bool callnow=true)
void	removeDynamicParameter (std::string const &name, bool throw_if_not_found=true)
void	setPath (std::string const &path)
std::filesystem::path	absolutePath (std::filesystem::path const &path="")
Public Member Functions inherited from jevois::ParameterRegistry
virtual	~ParameterRegistry ()

Related Symbols
(Note that these are not member symbols.)
	JEVOIS_DECLARE_PARAMETER (afac, float, "Factor applied to acceleration values for display, or 0 to not display", 100.0F, ParamCateg)
	Parameter.
	JEVOIS_DECLARE_PARAMETER (gfac, float, "Factor applied to gyroscope values for display, or 0 to not display", 0.5F, ParamCateg)
	Parameter.
	JEVOIS_DECLARE_PARAMETER (mfac, float, "Factor applied to magnetometer values for display, or 0 to not display", 3.0F, ParamCateg)
	Parameter.

Additional Inherited Members
Protected Member Functions inherited from jevois::Component
virtual void	preInit ()
virtual void	postInit ()
virtual void	preUninit ()
virtual void	postUninit ()
virtual void	preInit ()
virtual void	postInit ()
virtual void	preUninit ()
virtual void	postUninit ()
Protected Member Functions inherited from jevois::ParameterRegistry
void	addParameter (ParameterBase *const param)
void	removeParameter (ParameterBase *const param)
void	callbackInitCall ()

Detailed Description

Plot raw IMU readings on top of video.

As an optional hardware upgrade, one can install a global shutter sensor into JeVois (an OnSemi AR0135 1.2MP), which also includes on its custom circuit board for JeVois an inertial measurement unit (IMU). The IMU is a 9-degrees-of-freedom (9DOF) TDK InvenSense ICM-20948 (with 3-axis accelerometer, 3-axis gyroscope, and 3-axis magnetometer). This IMU also includes a digital motion processing unit (small programmable processor inside the IMU chip), which allows it to compute and filter Euler angles or quaternions directly inside the IMU chip.

This module only works with optional JeVois sensors that include an IMU! The base JeVois-A33 smart camera does not have an onboard IMU.

This module demonstrates the RAW and FIFO modes of the IMU.

The specifications of this chip are quite impressive:

• 3-axis 16-bit accelerometer with full-range sensitivity selectable to +/-2g, +/-4g, +/-8g, and +/-16g.
• Accelerometer data rate from 4 Hz to 1125 Hz.
• 3-axis 16-bit gyroscope with full-range sensitivity selectable to +/-250dps (degrees/s), +/-500dps, +/-1000dps, and +/-2000dps.
• Gyroscope data rate from 4 Hz to 1125 Hz.
• 3-axis 16-bit magnetometer (compass) with wide range of +/-4900uT (micro Tesla).
• Magnetometer data rates 10 Hz, 20 Hz, 50 Hz, or 100 Hz.
• 16-bit temperature sensor with readout rate of up to 8 kHz.
• RAW data mode (get current sensor values at any time), buffered (FIFO) data mode (sensor values accumulate into a FIFO at a fixed rate), and digital motion processing mode (DMP; raw data is processed on-chip).
• On-chip digital motion processor (DMP) can compute, inside the IMU chip itself:
  • quaternion 6 (uses accel + gyro),
  • quaternion 9 (uses accel + gyro + compass),
  • geomag quaternion (uses accel + compass),
  • flip/pickup detection,
  • step detection and counting,
  • basic activity recognition: drive, walk, run, bike, tilt, still.

With quaternions computed on-chip, with an algorithm that gets sensor data at a highly accurate, fixed rate, and applies various calibrations, drift corrections, and compensations on the fly, one gets highly accurate real-time estimate of the sensor's pose in the 3D world and of how it is moving.

Note that communication with the IMU is over a 400kHz I2C bus, which may limit data readout rate depending on which data is requested from the IMU.

This IMU has 3 basic modes of operation (parameter mode, which can only be set in params.cfg):

• RAW: One can access the latest raw sensor data at any time using the getRaw() or get() functions. This is the simplest mode of operation. One disadvantage is that if you are not calling get() at a perfectly regular interval, there will be some time jitter in your readouts. The IMU does not provide any time stamps for its data.
• FIFO: In this mode, data from the sensor is piled up into a 1 kbyte FIFO buffer at a precise, constant rate (when all three of accelerometer, gyroscope, and magnetometer are on, the gyro rate determines the FIFO buffering rate). Main advantage is that you can then read out the data without having to worry about calling getRaw() or get() at a highly precise interval. But you need to be careful that the FIFO can fill up and overflow very quickly when using high sensor data rates.
• DMP: In this mode, data is captured from the sensor at an accurate, fixed rate, and is fed to the on-chip digital motion processor (DMP). The DMP then computes quaternions, activity recognition, etc and pushes data packets into the FIFO as results from these algorithms become available.

Author

Laurent Itti

Videomapping:

YUYV 640 512 30.0 YUYV 640 480 30.0 JeVois DemoIMU

Email:

itti@usc.edu

Address:

University of Southern California, HNB-07A, 3641 Watt Way, Los Angeles, CA 90089-2520, USA

Copyright

Copyright (C) 2018 by Laurent Itti, iLab and the University of Southern California

Main URL:

http://jevois.org

Support URL:

http://jevois.org/doc

Other URL:

http://iLab.usc.edu

License:

GPL v3

Distribution:

Unrestricted

Restrictions:

None

Definition at line 112 of file DemoIMU.C.

Constructor & Destructor Documentation

DemoIMU()

DemoIMU::DemoIMU ( std::string const &  instance )

inline

Constructor.

Definition at line 116 of file DemoIMU.C.

~DemoIMU()

virtual DemoIMU::~DemoIMU ( )

inlinevirtual

Virtual destructor for safe inheritance.

Definition at line 120 of file DemoIMU.C.

Member Function Documentation

process() [1/2]

virtual void DemoIMU::process ( jevois::InputFrame &&  inframe, jevois::GUIhelper &  helper  )

inlineoverridevirtual

Processing function with GUI output.

Reimplemented from jevois::Module.

Definition at line 204 of file DemoIMU.C.

References jevois::IMUdata::ax(), jevois::IMUdata::ay(), jevois::IMUdata::az(), jevois::GUIhelper::drawInputFrame(), jevois::GUIhelper::endFrame(), jevois::IMUdata::gx(), jevois::IMUdata::gy(), jevois::IMUdata::gz(), jevois::GUIhelper::iinfo(), jevois::GUIhelper::itext(), jevois::IMUdata::magovf, jevois::IMUdata::mx(), jevois::IMUdata::my(), jevois::IMUdata::mz(), jevois::sformat(), jevois::Timer::start(), jevois::GUIhelper::startFrame(), jevois::Timer::stop(), and jevois::IMUdata::temp().

process() [2/2]

virtual void DemoIMU::process ( jevois::InputFrame &&  inframe, jevois::OutputFrame &&  outframe  )

inlineoverridevirtual

Processing function.

Reimplemented from jevois::Module.

Definition at line 123 of file DemoIMU.C.

References jevois::IMUdata::ax(), jevois::IMUdata::ay(), jevois::IMUdata::az(), jevois::yuyv::Black, jevois::RawImage::buf, jevois::yuyv::DarkGreen, jevois::yuyv::DarkPink, jevois::yuyv::DarkTeal, jevois::rawimage::drawFilledRect(), jevois::rawimage::drawLine(), jevois::RawImage::fmt, jevois::IMUdata::gx(), jevois::IMUdata::gy(), jevois::IMUdata::gz(), h, jevois::RawImage::height, jevois::yuyv::LightGreen, jevois::yuyv::LightPink, jevois::yuyv::LightTeal, jevois::IMUdata::magovf, jevois::yuyv::MedGreen, jevois::yuyv::MedPink, jevois::yuyv::MedTeal, jevois::IMUdata::mx(), jevois::IMUdata::my(), jevois::IMUdata::mz(), jevois::RawImage::pixels(), jevois::RawImage::pixelsw(), jevois::RawImage::require(), jevois::sformat(), jevois::IMUdata::temp(), jevois::yuyv::White, jevois::RawImage::width, and jevois::rawimage::writeText().

Friends And Related Symbol Documentation

JEVOIS_DECLARE_PARAMETER() [1/3]

JEVOIS_DECLARE_PARAMETER ( afac  , float  , "Factor applied to acceleration values for  display, or 0 to not display"  , 100.  0F, ParamCateg    )

related

Parameter.

JEVOIS_DECLARE_PARAMETER() [2/3]

JEVOIS_DECLARE_PARAMETER ( gfac  , float  , "Factor applied to gyroscope values for  display, or 0 to not display"  , 0.  5F, ParamCateg    )

related

Parameter.

JEVOIS_DECLARE_PARAMETER() [3/3]

JEVOIS_DECLARE_PARAMETER ( mfac  , float  , "Factor applied to magnetometer values for  display, or 0 to not display"  , 3.  0F, ParamCateg    )

related

Parameter.

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The documentation for this class was generated from the following file:

• src/Modules/DemoIMU/DemoIMU.C