IMU

Detailed Description

Defines the IMU sensor.

Data Structures
struct	dwIMUFrame
	An IMU frame containing sensor readings from the IMU sensor. More...

Enumerations
enum	dwIMUFlags {   DW_IMU_HEADING = 1 << 1,   DW_IMU_ROLL = 1 << 2,   DW_IMU_PITCH = 1 << 3,   DW_IMU_YAW = 1 << 4,   DW_IMU_QUATERNION_X = 1 << 5,   DW_IMU_QUATERNION_Y = 1 << 6,   DW_IMU_QUATERNION_Z = 1 << 7,   DW_IMU_QUATERNION_W = 1 << 8,   DW_IMU_ROLL_RATE = 1 << 9,   DW_IMU_PITCH_RATE = 1 << 10,   DW_IMU_YAW_RATE = 1 << 11,   DW_IMU_ACCELERATION_X = 1 << 12,   DW_IMU_ACCELERATION_Y = 1 << 13,   DW_IMU_ACCELERATION_Z = 1 << 14,   DW_IMU_MAGNETOMETER_X = 1 << 15,   DW_IMU_MAGNETOMETER_Y = 1 << 16,   DW_IMU_MAGNETOMETER_Z = 1 << 17 }
	Each flag shows if that value is valid in this IMU frame. More...
enum	dwIMUHeadingType {   DW_IMU_HEADING_TRUE = 0,   DW_IMU_HEADING_MAGNECTIC = 1 }
	Types of the heading degree. More...

Functions
DW_API_PUBLIC dwStatus	dwSensorIMU_popMessage (dwIMUFrame *frame, dwSensorHandle_t sensor)
	Returns any IMU data previously processed through the raw data stream. More...
DW_API_PUBLIC dwStatus	dwSensorIMU_processRaw (const uint8_t *data, size_t size, dwSensorHandle_t sensor)
	Reads the IMU frame from raw data. More...
DW_API_PUBLIC dwStatus	dwSensorIMU_readFrame (dwIMUFrame *frame, dwTime_t timeout_us, dwSensorHandle_t sensor)
	Reads the next IMU frame from the sensor within a given timeout. More...

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Data Structure Documentation

dwIMUFrame

struct dwIMUFrame

Data Fields
float64_t	acceleration[3]	Acceleration in X, Y, and Z directions [m/s^2].
uint32_t	flags	The flags to show which values are valid in this IMU frame.
float64_t	heading	Heading of the IMU measured in respect to the ENU system [degrees], i.e., compass.
dwIMUHeadingType	headingType	Type of the heading information.
float64_t	magnetometer[3]	Measurement of the magnetometer unit in X, Y, and Z directions [utesla].
float64_t	orientation[3]	Roll, pitch, and yaw angle of the orientation returned by the IMU [degree].
float64_t	orientationQuaternion[4]	Quaternion representation (x, y, z, w) of the orientation returned by the IMU.
dwTime_t	timestamp_us	Timestamp for the current message. Indicates when it's first received [usec].
float64_t	turnrate[3]	Roll, pitch, and yaw turn rate (i.e., gyroscope)[rad/s].

Enumeration Type Documentation

dwIMUFlags

enum dwIMUFlags

Each flag shows if that value is valid in this IMU frame.

Enumerator
DW_IMU_HEADING	Value of dwIMUFrame.heading is valid.
DW_IMU_ROLL	Value of dwIMUFrame.orientation[0] is valid.
DW_IMU_PITCH	Value of dwIMUFrame.orientation[1] is valid.
DW_IMU_YAW	Value of dwIMUFrame.orientation[2] is valid.
DW_IMU_QUATERNION_X
DW_IMU_QUATERNION_Y	!< Value of dwIMUFrame.orientationQuaternion[0] is valid.
DW_IMU_QUATERNION_Z	!< Value of dwIMUFrame.orientationQuaternion[1] is valid.
DW_IMU_QUATERNION_W	!< Value of dwIMUFrame.orientationQuaternion[2] is valid.
DW_IMU_ROLL_RATE	!< Value of dwIMUFrame.orientationQuaternion[3] is valid. Value of dwIMUFrame.turnrate[0] is valid.
DW_IMU_PITCH_RATE	Value of dwIMUFrame.turnrate[1] is valid.
DW_IMU_YAW_RATE	Value of dwIMUFrame.turnrate[2] is valid.
DW_IMU_ACCELERATION_X	Value of dwIMUFrame.acceleration[0] is valid.
DW_IMU_ACCELERATION_Y	Value of dwIMUFrame.acceleration[1] is valid.
DW_IMU_ACCELERATION_Z	Value of dwIMUFrame.acceleration[2] is valid.
DW_IMU_MAGNETOMETER_X	Value of dwIMUFrame.magnetometer[0] is valid.
DW_IMU_MAGNETOMETER_Y	Value of dwIMUFrame.magnetometer[1] is valid.
DW_IMU_MAGNETOMETER_Z	Value of dwIMUFrame.magnetometer[2] is valid.

Definition at line 60 of file IMU.h.

dwIMUHeadingType

enum dwIMUHeadingType

Types of the heading degree.

Enumerator
DW_IMU_HEADING_TRUE	True heading. dwIMUFrame.heading points towards true north.
DW_IMU_HEADING_MAGNECTIC	Magnectic heading. dwIMUFrame.heading points towards magnetic north.

Definition at line 88 of file IMU.h.

Function Documentation

dwSensorIMU_popMessage()

DW_API_PUBLIC dwStatus dwSensorIMU_popMessage	(	dwIMUFrame *	frame,
		dwSensorHandle_t	sensor
	)

Returns any IMU data previously processed through the raw data stream.

This happens on the CPU thread where the function is called, incurring on additional load on that thread.

Parameters

[out]	frame	Pointer to an IMU frame structure to be filled with new data.
[in]	sensor	Sensor handle of the sensor previously created with dwSAL_createSensor().

Returns

DW_INVALID_HANDLE - if given sensor handle is invalid.
DW_INVALID_ARGUMENTS - if given arguments are invalid.
DW_NOT_AVAILABLE - if no more data is available
DW_SUCCESS

dwSensorIMU_processRaw()

DW_API_PUBLIC dwStatus dwSensorIMU_processRaw	(	const uint8_t *	data,
		size_t	size,
		dwSensorHandle_t	sensor
	)

Reads the IMU frame from raw data.

Any processed messages can be picked up using the dwSensorIMU_popMessage() method.

Parameters

[in]	data	Pointer to the raw data, which can be processed by the IMU module.
[in]	size	The size of the raw data, in bytes.
[in]	sensor	Sensor handle of the IMU sensor previously created with dwSAL_createSensor().

Returns

DW_INVALID_HANDLE - if given sensor handle is invalid
DW_INVALID_ARGUMENTS - if given arguments are invalid
DW_NOT_READY - if more data needs to be passed in
DW_SUCCESS

dwSensorIMU_readFrame()

DW_API_PUBLIC dwStatus dwSensorIMU_readFrame	(	dwIMUFrame *	frame,
		dwTime_t	timeout_us,
		dwSensorHandle_t	sensor
	)

Reads the next IMU frame from the sensor within a given timeout.

The method blocks until either a new valid frame is received from the sensor or the given timeout is exceeded.

Parameters

[out]	frame	A pointer to an IMU frame structure to be filled with new data.
[in]	timeout_us	Timeout, in us, to wait for a new message. Special values: DW_TIMEOUT_INFINITE - to wait infinitly. Zero - means polling of internal queue.
[in]	sensor	Sensor handle of the IMU sensor previously created with dwSAL_createSensor().

Returns

DW_INVALID_HANDLE - if given sensor handle is invalid
DW_INVALID_ARGUMENTS - if given arguments are invalid
DW_TIME_OUT - if operation has timeout
DW_NOT_AVAILABLE - if sensor has not been started or data is not available in polling mode.
DW_SAL_SENSOR_ERROR - if there was an i/o or bus error.
DW_SUCCESS