JeVoisBase  1.20
JeVois Smart Embedded Machine Vision Toolkit Base Modules
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DemoIMU Class Reference
JeVoisBase machine vision modules

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

Inheritance diagram for DemoIMU:
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Collaboration diagram for DemoIMU:
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Public Member Functions

 DemoIMU (std::string const &instance)
 Constructor. More...
 
virtual ~DemoIMU ()
 Virtual destructor for safe inheritance. More...
 
virtual void process (jevois::InputFrame &&inframe, jevois::OutputFrame &&outframe) override
 Processing function. More...
 
- Public Member Functions inherited from jevois::Module
 Module (std::string const &instance)
 
virtual ~Module ()
 
virtual void process (InputFrame &&inframe)
 
virtual void process (InputFrame &&inframe, GUIhelper &helper)
 
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
 
Engine * engine () const
 
bool initialized () const
 
const std::string & className () const
 
const std::string & 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)
 
void unFreezeParam (std::string const &paramdescriptor)
 
void freezeAllParams ()
 
void unFreezeAllParams ()
 
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)
 
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
 
Engine * engine () const
 
bool initialized () const
 
const std::string & className () const
 
const std::string & 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)
 
void unFreezeParam (std::string const &paramdescriptor)
 
void freezeAllParams ()
 
void unFreezeAllParams ()
 
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)
 
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 Functions

(Note that these are not member functions.)

 JEVOIS_DECLARE_PARAMETER (afac, float, "Factor applied to acceleration values for display, or 0 to not display", 100.0F, ParamCateg)
 Parameter. More...
 
 JEVOIS_DECLARE_PARAMETER (gfac, float, "Factor applied to gyroscope values for display, or 0 to not display", 0.5F, ParamCateg)
 Parameter. More...
 
 JEVOIS_DECLARE_PARAMETER (mfac, float, "Factor applied to magnetometer values for display, or 0 to not display", 3.0F, ParamCateg)
 Parameter. More...
 

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()

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::RawImage::buf, jevois::rawimage::drawFilledRect(), jevois::rawimage::drawLine(), jevois::RawImage::fmt, jevois::IMUdata::gx(), jevois::IMUdata::gy(), jevois::IMUdata::gz(), h, jevois::RawImage::height, jevois::IMUdata::magovf, jevois::IMUdata::mx(), jevois::IMUdata::my(), jevois::IMUdata::mz(), jevois::RawImage::pixels(), jevois::RawImage::pixelsw(), jevois::RawImage::require(), jevois::sformat(), jevois::IMUdata::temp(), demo::w, jevois::RawImage::width, and jevois::rawimage::writeText().

Friends And Related Function 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.

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