Class to drive the BNO080 9-axis IMU. More...

#include <BNO080.h>

Public Types
enum	Report { TOTAL_ACCELERATION = SENSOR_REPORTID_ACCELEROMETER, LINEAR_ACCELERATION = SENSOR_REPORTID_LINEAR_ACCELERATION, GRAVITY_ACCELERATION = SENSOR_REPORTID_GRAVITY, GYROSCOPE = SENSOR_REPORTID_GYROSCOPE_CALIBRATED, MAG_FIELD = SENSOR_REPORTID_MAGNETIC_FIELD_CALIBRATED, MAG_FIELD_UNCALIBRATED = SENSOR_REPORTID_MAGNETIC_FIELD_UNCALIBRATED, ROTATION = SENSOR_REPORTID_ROTATION_VECTOR, GEOMAGNETIC_ROTATION = SENSOR_REPORTID_GEOMAGNETIC_ROTATION_VECTOR, GAME_ROTATION = SENSOR_REPORTID_GAME_ROTATION_VECTOR, TAP_DETECTOR = SENSOR_REPORTID_TAP_DETECTOR, STABILITY_CLASSIFIER = SENSOR_REPORTID_STABILITY_CLASSIFIER, STEP_DETECTOR = SENSOR_REPORTID_STEP_DETECTOR, STEP_COUNTER = SENSOR_REPORTID_STEP_COUNTER, SIGNIFICANT_MOTION = SENSOR_REPORTID_SIGNIFICANT_MOTION, SHAKE_DETECTOR = SENSOR_REPORTID_SHAKE_DETECTOR }
	List of all sensor reports that the IMU supports. More...
enum	Stability { UNKNOWN = 0, ON_TABLE = 1, STATIONARY = 2, STABLE = 3, MOTION = 4 }
	Enum to represent the different stability types. More...
Public Member Functions
	BNO080 (Serial *debugPort, PinName user_SDApin, PinName user_SCLpin, PinName user_INTPin, PinName user_RSTPin, uint8_t i2cAddress=0x4a, int i2cPortSpeed=100000)
	Construct a BNO080, providing pins and parameters.
bool	begin ()
	Resets and connects to the IMU.
void	tare (bool zOnly=false)
	Tells the IMU to use its current rotation vector as the "zero" rotation vector and to reorient all outputs accordingly.
bool	enableCalibration (bool calibrateAccel, bool calibrateGyro, bool calibrateMag)
	Tells the IMU to begin a dynamic sensor calibration.
bool	saveCalibration ()
	Saves the calibration started with startCalibration() and ends the calibration.
void	setSensorOrientation (Quaternion orientation)
	Sets the orientation quaternion, telling the sensor how it's mounted in relation to world space.
bool	setPermanentOrientation (Quaternion orientation)
	Sets the orientation quaternion, telling the sensor how it's mounted in relation to world space.
bool	updateData ()
	Checks for new data packets queued on the IMU.
uint8_t	getReportStatus (Report report)
	Gets the status of a report as a 2 bit number.
const char *	getReportStatusString (Report report)
	Get a string for printout describing the status of a sensor.
bool	hasNewData (Report report)
	Checks if a specific report has gotten new data since the last call to this function.
void	enableReport (Report report, uint16_t timeBetweenReports)
	Enable a data report from the IMU.
void	disableReport (Report report)
	Disable a data report from the IMU.
uint32_t	getSerialNumber ()
	Gets the serial number (used to uniquely identify each individual device).
float	getRange (Report report)
	Gets the range of a report as reported by the IMU.
float	getResolution (Report report)
	Gets the resolution of a report as reported by the IMU.
float	getPower (Report report)
	Get the power used by a report when it's operating, according to the IMU.
float	getMinPeriod (Report report)
	Gets the smallest polling period that a report supports.
float	getMaxPeriod (Report report)
	Gets the larges polling period that a report supports.
void	printMetadataSummary (Report report)
	Prints a summary of a report's metadata to the debug stream.
Data Fields
TVector3	totalAcceleration
	Readout from Accleration report.
TVector3	linearAcceleration
	Readout from Linear Acceleration report.
TVector3	gravityAcceleration
	Readout from Gravity report.
TVector3	gyroRotation
	Readout from Calibrated Gyroscope report Represents the angular velocities of the chip in rad/s in the X, Y, and Z axes.
TVector3	magField
	Readout from the Magnetic Field Calibrated report.
TVector3	magFieldUncalibrated
	Readout from the Magnetic Field Uncalibrated report.
TVector3	hardIronOffset
	Auxiliary readout from the Magnetic Field Uncalibrated report.
Quaternion	rotationVector
	Readout from the Rotation Vector report.
float	rotationAccuracy
	Auxiliary accuracy readout from the Rotation Vector report.
Quaternion	gameRotationVector
	Readout from the Game Rotation Vector report.
Quaternion	geomagneticRotationVector
	Readout from the Geomagnetic Rotation Vector report.
float	geomagneticRotationAccuracy
	Auxiliary accuracy readout from the Geomagnetic Rotation Vector report.
bool	tapDetected
	Tap readout from the Tap Detector report.
bool	doubleTap
	Whether the last tap detected was a single or double tap.
Stability	stability
	Readout from the stability classifier.
bool	stepDetected
	Readout from the Step Detector report.
uint16_t	stepCount
	Readout from the Step Counter report.
bool	significantMotionDetected
	Readout from the Significant Motion Detector report.
bool	shakeDetected
	Readout from the Shake Detector report.

uint8_t	majorSoftwareVersion
	Version info read from the IMU when it starts up.

bool	xAxisShake
	The axis/axes that shaking was detected in in the latest shaking report.

Detailed Description

Class to drive the BNO080 9-axis IMU.

There should be one instance of this class per IMU chip. I2C address and pin assignments are passed in the constructor.

Definition at line 38 of file BNO080.h.

Member Enumeration Documentation

enum Report

List of all sensor reports that the IMU supports.

Enumerator:

TOTAL_ACCELERATION	Total acceleration of the IMU in world space. See BNO datasheet section 2.1.1
LINEAR_ACCELERATION	Acceleration of the IMU not including the acceleration of gravity. See BNO datasheet section 2.1.1
GRAVITY_ACCELERATION	Acceleration of gravity felt by the IMU. See BNO datasheet section 2.1.1
GYROSCOPE	(calibrated) gyroscope reading of the rotational speed of the IMU. See BNO datasheet section 2.1.2
MAG_FIELD	(calibrated) reading of Earth's magnetic field levels. See BNO datasheet section 2.1.3
MAG_FIELD_UNCALIBRATED	Uncalibrated reading of magnetic field levels, without any hard iron offsets applied See BNO datasheet section 2.1.3.
ROTATION	Fused reading of the IMU's rotation in space using all three sensors. This is the most accurate reading of absolute orientation that the IMU can provide. See BNO datasheet section 2.2.4
GEOMAGNETIC_ROTATION	Fused reading of rotation from accelerometer and magnetometer readings. This report is designed to decrease power consumption (by turning off the gyroscope) in exchange for reduced responsiveness.
GAME_ROTATION	Fused reading of the IMU's rotation in space. Unlike the regular rotation vector, the Game Rotation Vector is not referenced against the magnetic field and the "zero yaw" point is arbitrary. See BNO datasheet section 2.2.2
TAP_DETECTOR	Detects a user tapping on the device containing the IMU. See BNO datasheet section 2.4.2
STABILITY_CLASSIFIER	Detects whether the device is on a table, being held stably, or being moved. See BNO datasheet section 2.4.1
STEP_DETECTOR	Detects a user taking a step with the IMU worn on their person. See BNO datasheet section 2.4.3
STEP_COUNTER	Detects how many steps a user has taken. See BNO datasheet section 2.4.4
SIGNIFICANT_MOTION	Detects when the IMU has made a "significant" motion, defined as moving a few steps and/or accelerating significantly. NOTE: this report automatically disables itself after sending a report, so you'll have to reenable it each time a motion i s detected. See BNO datasheet section 2.4.6
SHAKE_DETECTOR	Detects when the IMU is being shaken. See BNO datasheet section 2.4.7

Definition at line 126 of file BNO080.h.

enum Stability

Enum to represent the different stability types.

See BNO datasheet section 2.4.1 and SH-2 section 6.5.31.2 for details.

Enumerator:

UNKNOWN	Unknown stability type.
ON_TABLE	At rest on a stable surface with very little motion.
STATIONARY	Motion is stable, but the duration requirement for stability has not been met. Can only occur during gyroscope calibration (why? beats me!)
STABLE	Stable (has been below the acceleration threshold for the required duration)
MOTION	IMU is moving.

Definition at line 325 of file BNO080.h.

Constructor & Destructor Documentation

BNO080	(	Serial *	debugPort,
		PinName	user_SDApin,
		PinName	user_SCLpin,
		PinName	user_INTPin,
		PinName	user_RSTPin,
		uint8_t	i2cAddress = `0x4a`,
		int	i2cPortSpeed = `100000`
	)

Construct a BNO080, providing pins and parameters.

This doesn't actally initialize the chip, you will need to call begin() for that.

NOTE: while some schematics tell you to connect the BOOTN pin to the processor, this driver does not use or require it. Just tie it to VCC per the datasheet.

Parameters:

debugPort	Serial port to write output to. Cannot be nullptr.
user_SDApin	Hardware I2C SDA pin connected to the IMU
user_SCLpin	Hardware I2C SCL pin connected to the IMU
user_INTPin	Input pin connected to HINTN
user_RSTPin	Output pin connected to NRST
i2cAddress	I2C address. The BNO defaults to 0x4a, but can also be set to 0x4b via a pin.
i2cPortSpeed	I2C frequency. The BNO's max is 400kHz.

Definition at line 73 of file BNO080.cpp.

Member Function Documentation

bool begin ( )

Resets and connects to the IMU.

Verifies that it's connected, and reads out its version info into the class variables above.

If this function is failing, it would be a good idea to turn on BNO_DEBUG in the cpp file to get detailed output.

Returns:: whether or not initialization was successful

Definition at line 103 of file BNO080.cpp.

void disableReport ( Report report )

Disable a data report from the IMU.

Parameters:

report The report to disable.

Definition at line 407 of file BNO080.cpp.

bool enableCalibration	(	bool	calibrateAccel,
		bool	calibrateGyro,
		bool	calibrateMag
	)

Tells the IMU to begin a dynamic sensor calibration.

To calibrate the IMU, call this function and move the IMU according to the instructions in the "BNO080 Sensor Calibration Procedure" app note (http://www.hillcrestlabs.com/download/59de9014566d0727bd002ae7).

To tell when the calibration is complete, look at the status bits for Game Rotation Vector (for accel and gyro) and Magnetic Field (for the magnetometer).

The gyro and accelerometer should only need to be calibrated once, but the magnetometer will need to be recalibrated every time the orientation of ferrous metals around the IMU changes (e.g. when it is put into a new enclosure).

The new calibration will not be saved in flash until you call saveCalibration().

NOTE: calling this with all false values will cancel any calibration in progress. However, the calibration data being created will remain in use until the next chip reset (I think!)

Parameters:

calibrateAccel	Whether to calibrate the accelerometer.
calibrateGyro	Whether to calibrate the gyro.
calibrateMag	Whether to calibrate the magnetometer.

Returns:: whether the operation succeeded

Definition at line 215 of file BNO080.cpp.

void enableReport	(	Report	report,
		uint16_t	timeBetweenReports
	)

Enable a data report from the IMU.

Look at the comments above to see what the reports do. This function checks your polling period against the report's max speed in the IMU's metadata, and reports an error if you're trying to poll too fast.

Parameters:

timeBetweenReports time in milliseconds between data updates.

Definition at line 384 of file BNO080.cpp.

float getMaxPeriod ( Report report )

Gets the larges polling period that a report supports.

Some reports don't have a max period, in which case this function will return -1.0.

Returns:: Period in seconds, or -1.0 on error.

Definition at line 455 of file BNO080.cpp.

float getMinPeriod ( Report report )

Gets the smallest polling period that a report supports.

Returns:: Period in seconds.

Definition at line 448 of file BNO080.cpp.

float getPower ( Report report )

Get the power used by a report when it's operating, according to the IMU.

Parameters:

report

Returns:: Power used in mA.

Definition at line 439 of file BNO080.cpp.

float getRange ( Report report )

Gets the range of a report as reported by the IMU.

Units are the same as the report's output data.

Returns:

Definition at line 424 of file BNO080.cpp.

uint8_t getReportStatus ( Report report )

Gets the status of a report as a 2 bit number.

per SH-2 section 6.5.1, this is interpreted as:
0 - unreliable
1 - accuracy low
2 - accuracy medium
3 - accuracy high
of course, these are only updated if a given report is enabled.

Parameters:

report

Returns:

Definition at line 345 of file BNO080.cpp.

const char * getReportStatusString ( Report report )

Get a string for printout describing the status of a sensor.

Returns:

Definition at line 355 of file BNO080.cpp.

float getResolution ( Report report )

Gets the resolution of a report as reported by the IMU.

Units are the same as the report's output data.

Parameters:

report

Returns:

Definition at line 432 of file BNO080.cpp.

uint32_t getSerialNumber ( )

Gets the serial number (used to uniquely identify each individual device).

NOTE: this function should work according to the datasheet, but the device I was testing with appears to have an empty serial number record as shipped, and I could never get anything out of it. Your mileage may vary.

Returns:: The serial number, or 0 on error.

Definition at line 413 of file BNO080.cpp.

bool hasNewData ( Report report )

Checks if a specific report has gotten new data since the last call to this function.

Parameters:

report The report to check.

Returns:: Whether the report has received new data.

Definition at line 371 of file BNO080.cpp.

void printMetadataSummary ( Report report )

Prints a summary of a report's metadata to the debug stream.

Should be useful for debugging and setting up reports since lots of this data isn't given in the datasheets.

Note: to save string constant space, this function is only available when BNO_DEBUG is 1.

Definition at line 467 of file BNO080.cpp.

bool saveCalibration ( )

Saves the calibration started with startCalibration() and ends the calibration.

You will want to call this once the status bits read as "accuracy high".

WARNING: if you paid for a factory calibrated IMU, then this WILL OVERWRITE THE FACTORY CALIBRATION in whatever sensors are being calibrated. Use with caution!

Returns:: whether the operation succeeded

Definition at line 256 of file BNO080.cpp.

bool setPermanentOrientation ( Quaternion orientation )

Sets the orientation quaternion, telling the sensor how it's mounted in relation to world space.

See page 40 of the BNO080 datasheet.

Unlike setSensorOrientation(), this setting will persist across sensor restarts. However, it will also take a few hundred milliseconds to write.

Parameters:

orientation quaternion mapping from IMU space to world space.

Returns:: true if the operation succeeded, false if it failed.

void setSensorOrientation ( Quaternion orientation )

Sets the orientation quaternion, telling the sensor how it's mounted in relation to world space.

See page 40 of the BNO080 datasheet.

NOTE: this driver provides the macro SQRT_2 to help with entering values from that table.

NOTE 2: this setting does not persist and will have to be re-applied every time the chip is reset. Use setPermanentOrientation() for that.

Parameters:

orientation quaternion mapping from IMU space to world space.

Definition at line 289 of file BNO080.cpp.

void tare ( bool zOnly = false )

Tells the IMU to use its current rotation vector as the "zero" rotation vector and to reorient all outputs accordingly.

Parameters:

zOnly If true, only the rotation about the Z axis (the heading) will be tared.

Definition at line 197 of file BNO080.cpp.

bool updateData ( )

Checks for new data packets queued on the IMU.

If there are packets queued, receives all of them and updates the class variables with the results.

Returns:: True iff new data packets of any kind were received. If you need more fine-grained data change reporting, check out hasNewData().

Definition at line 324 of file BNO080.cpp.

Field Documentation

bool doubleTap

Whether the last tap detected was a single or double tap.

Definition at line 318 of file BNO080.h.

Quaternion gameRotationVector

Readout from the Game Rotation Vector report.

Represents the rotation of the IMU in radians. Unlike the regular rotation vector, the Game Rotation Vector is not referenced against the magnetic field and the "zero yaw" point is arbitrary.

Definition at line 295 of file BNO080.h.

float geomagneticRotationAccuracy

Auxiliary accuracy readout from the Geomagnetic Rotation Vector report.

Represents the estimated accuracy of the rotation vector in radians.

Definition at line 307 of file BNO080.h.

Quaternion geomagneticRotationVector

Readout from the Geomagnetic Rotation Vector report.

Represents the geomagnetic rotation of the IMU (relative to magnetic north) in radians.

Definition at line 301 of file BNO080.h.

TVector3 gravityAcceleration

Readout from Gravity report.

Represents the force of gravity in m/s^2 felt by the BNO's accelerometer.

Definition at line 252 of file BNO080.h.

TVector3 gyroRotation

Readout from Calibrated Gyroscope report Represents the angular velocities of the chip in rad/s in the X, Y, and Z axes.

Definition at line 258 of file BNO080.h.

TVector3 hardIronOffset

Auxiliary readout from the Magnetic Field Uncalibrated report.

Represents the hard iron offsets that the chip is using in each axis in uT.

Definition at line 276 of file BNO080.h.

TVector3 linearAcceleration

Readout from Linear Acceleration report.

Represents acceleration felt in m/s^2 by the BNO's accelerometer not including the force of gravity.

Definition at line 246 of file BNO080.h.

TVector3 magField

Readout from the Magnetic Field Calibrated report.

Represents the magnetic field read by the chip in uT in the X, Y, and Z axes

Definition at line 264 of file BNO080.h.

TVector3 magFieldUncalibrated

Readout from the Magnetic Field Uncalibrated report.

Represents the magnetic field read by the chip in uT in the X, Y, and Z axes, without hard iron offsets applied

Definition at line 270 of file BNO080.h.

uint8_t majorSoftwareVersion

Version info read from the IMU when it starts up.

Definition at line 228 of file BNO080.h.

float rotationAccuracy

Auxiliary accuracy readout from the Rotation Vector report.

Represents the estimated accuracy of the rotation vector in radians.

Definition at line 288 of file BNO080.h.

Quaternion rotationVector

Readout from the Rotation Vector report.

Represents the rotation of the IMU (relative to magnetic north) in radians.

Definition at line 282 of file BNO080.h.

bool shakeDetected

Readout from the Shake Detector report.

This flag is set to true whenever shaking is detected, and you should manually clear it when you have processed the event.

Definition at line 372 of file BNO080.h.

bool significantMotionDetected

Readout from the Significant Motion Detector report.

This flag is set to true whenever significant motion is detected, and you should manually clear it when you have processed the event.

Definition at line 366 of file BNO080.h.

Stability stability

Readout from the stability classifier.

Current stability status of the IMU.

Definition at line 348 of file BNO080.h.

uint16_t stepCount

Readout from the Step Counter report.

This count increases as the user takes steps, but can also decrease if the IMU decides that a motion was not a step.

Definition at line 360 of file BNO080.h.

bool stepDetected

Readout from the Step Detector report.

This flag is set to true whenever a step is detected, and you should manually clear it when you have processed the step.

Definition at line 354 of file BNO080.h.

bool tapDetected

Tap readout from the Tap Detector report.

This flag is set to true whenever a tap is detected, and you should manually clear it when you have processed the tap.

Definition at line 313 of file BNO080.h.

TVector3 totalAcceleration

Readout from Accleration report.

Represents total acceleration in m/s^2 felt by the BNO's accelerometer.

Definition at line 240 of file BNO080.h.

bool xAxisShake

The axis/axes that shaking was detected in in the latest shaking report.

Definition at line 376 of file BNO080.h.

Type:	Library
Created:	30 Jul 2019
Imports:	14
Forks:	0
Commits:	10
Dependents:	1
Dependencies:	0
Followers:	10

BNO080 Class Reference

Public Types

Public Member Functions

Data Fields

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation

Repository toolbox

Repository details

Important Information for this Arm website

BNO080 Class Reference

Public Types

Public Member Functions

Data Fields

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation

Repository toolbox

Repository details

Important Information for this Arm website

Access Warning