Class: Tinkerforge::BrickIMU

Inherits:
Device
  • Object
show all
Defined in:
lib/tinkerforge/brick_imu.rb

Overview

Full fledged AHRS with 9 degrees of freedom

Constant Summary collapse

DEVICE_IDENTIFIER =

:nodoc:

16
DEVICE_DISPLAY_NAME =

:nodoc:

'IMU Brick'
CALLBACK_ACCELERATION =

This callback is triggered periodically with the period that is set by BrickIMU#set_acceleration_period. The parameters are the acceleration for the x, y and z axis.

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CALLBACK_MAGNETIC_FIELD =

This callback is triggered periodically with the period that is set by BrickIMU#set_magnetic_field_period. The parameters are the magnetic field for the x, y and z axis.

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CALLBACK_ANGULAR_VELOCITY =

This callback is triggered periodically with the period that is set by BrickIMU#set_angular_velocity_period. The parameters are the angular velocity for the x, y and z axis.

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CALLBACK_ALL_DATA =

This callback is triggered periodically with the period that is set by BrickIMU#set_all_data_period. The parameters are the acceleration, the magnetic field and the angular velocity for the x, y and z axis as well as the temperature of the IMU Brick.

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CALLBACK_ORIENTATION =

This callback is triggered periodically with the period that is set by BrickIMU#set_orientation_period. The parameters are the orientation (roll, pitch and yaw) of the IMU Brick in Euler angles. See BrickIMU#get_orientation for details.

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CALLBACK_QUATERNION =

This callback is triggered periodically with the period that is set by BrickIMU#set_quaternion_period. The parameters are the orientation (x, y, z, w) of the IMU Brick in quaternions. See BrickIMU#get_quaternion for details.

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FUNCTION_GET_ACCELERATION =

:nodoc:

1
FUNCTION_GET_MAGNETIC_FIELD =

:nodoc:

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FUNCTION_GET_ANGULAR_VELOCITY =

:nodoc:

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FUNCTION_GET_ALL_DATA =

:nodoc:

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FUNCTION_GET_ORIENTATION =

:nodoc:

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FUNCTION_GET_QUATERNION =

:nodoc:

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FUNCTION_GET_IMU_TEMPERATURE =

:nodoc:

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FUNCTION_LEDS_ON =

:nodoc:

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FUNCTION_LEDS_OFF =

:nodoc:

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FUNCTION_ARE_LEDS_ON =

:nodoc:

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FUNCTION_SET_ACCELERATION_RANGE =

:nodoc:

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FUNCTION_GET_ACCELERATION_RANGE =

:nodoc:

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FUNCTION_SET_MAGNETOMETER_RANGE =

:nodoc:

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FUNCTION_GET_MAGNETOMETER_RANGE =

:nodoc:

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FUNCTION_SET_CONVERGENCE_SPEED =

:nodoc:

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FUNCTION_GET_CONVERGENCE_SPEED =

:nodoc:

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FUNCTION_SET_CALIBRATION =

:nodoc:

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FUNCTION_GET_CALIBRATION =

:nodoc:

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FUNCTION_SET_ACCELERATION_PERIOD =

:nodoc:

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FUNCTION_GET_ACCELERATION_PERIOD =

:nodoc:

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FUNCTION_SET_MAGNETIC_FIELD_PERIOD =

:nodoc:

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FUNCTION_GET_MAGNETIC_FIELD_PERIOD =

:nodoc:

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FUNCTION_SET_ANGULAR_VELOCITY_PERIOD =

:nodoc:

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FUNCTION_GET_ANGULAR_VELOCITY_PERIOD =

:nodoc:

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FUNCTION_SET_ALL_DATA_PERIOD =

:nodoc:

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FUNCTION_GET_ALL_DATA_PERIOD =

:nodoc:

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FUNCTION_SET_ORIENTATION_PERIOD =

:nodoc:

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FUNCTION_GET_ORIENTATION_PERIOD =

:nodoc:

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FUNCTION_SET_QUATERNION_PERIOD =

:nodoc:

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FUNCTION_GET_QUATERNION_PERIOD =

:nodoc:

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FUNCTION_ORIENTATION_CALCULATION_ON =

:nodoc:

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FUNCTION_ORIENTATION_CALCULATION_OFF =

:nodoc:

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FUNCTION_IS_ORIENTATION_CALCULATION_ON =

:nodoc:

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FUNCTION_SET_SPITFP_BAUDRATE_CONFIG =

:nodoc:

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FUNCTION_GET_SPITFP_BAUDRATE_CONFIG =

:nodoc:

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FUNCTION_GET_SEND_TIMEOUT_COUNT =

:nodoc:

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FUNCTION_SET_SPITFP_BAUDRATE =

:nodoc:

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FUNCTION_GET_SPITFP_BAUDRATE =

:nodoc:

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FUNCTION_GET_SPITFP_ERROR_COUNT =

:nodoc:

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FUNCTION_ENABLE_STATUS_LED =

:nodoc:

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FUNCTION_DISABLE_STATUS_LED =

:nodoc:

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FUNCTION_IS_STATUS_LED_ENABLED =

:nodoc:

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FUNCTION_GET_PROTOCOL1_BRICKLET_NAME =

:nodoc:

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FUNCTION_GET_CHIP_TEMPERATURE =

:nodoc:

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FUNCTION_RESET =

:nodoc:

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FUNCTION_WRITE_BRICKLET_PLUGIN =

:nodoc:

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FUNCTION_READ_BRICKLET_PLUGIN =

:nodoc:

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FUNCTION_GET_IDENTITY =

:nodoc:

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CALIBRATION_TYPE_ACCELEROMETER_GAIN =

:nodoc:

0
CALIBRATION_TYPE_ACCELEROMETER_BIAS =

:nodoc:

1
CALIBRATION_TYPE_MAGNETOMETER_GAIN =

:nodoc:

2
CALIBRATION_TYPE_MAGNETOMETER_BIAS =

:nodoc:

3
CALIBRATION_TYPE_GYROSCOPE_GAIN =

:nodoc:

4
CALIBRATION_TYPE_GYROSCOPE_BIAS =

:nodoc:

5
COMMUNICATION_METHOD_NONE =

:nodoc:

0
COMMUNICATION_METHOD_USB =

:nodoc:

1
COMMUNICATION_METHOD_SPI_STACK =

:nodoc:

2
COMMUNICATION_METHOD_CHIBI =

:nodoc:

3
COMMUNICATION_METHOD_RS485 =

:nodoc:

4
COMMUNICATION_METHOD_WIFI =

:nodoc:

5
COMMUNICATION_METHOD_ETHERNET =

:nodoc:

6
COMMUNICATION_METHOD_WIFI_V2 =

:nodoc:

7

Constants inherited from Device

Device::DEVICE_IDENTIFIER_CHECK_MATCH, Device::DEVICE_IDENTIFIER_CHECK_MISMATCH, Device::DEVICE_IDENTIFIER_CHECK_PENDING, Device::RESPONSE_EXPECTED_ALWAYS_TRUE, Device::RESPONSE_EXPECTED_FALSE, Device::RESPONSE_EXPECTED_INVALID_FUNCTION_ID, Device::RESPONSE_EXPECTED_TRUE

Instance Attribute Summary

Attributes inherited from Device

#callback_formats, #expected_response_function_id, #expected_response_sequence_number, #high_level_callbacks, #registered_callbacks, #replaced, #uid

Instance Method Summary collapse

Methods inherited from Device

#check_validity, #dequeue_response, #enqueue_response, #get_api_version, #get_response_expected, #send_request, #set_response_expected, #set_response_expected_all

Constructor Details

#initialize(uid, ipcon) ⇒ BrickIMU

Creates an object with the unique device ID uid and adds it to the IP Connection ipcon.



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# File 'lib/tinkerforge/brick_imu.rb', line 119

def initialize(uid, ipcon)
  super uid, ipcon, DEVICE_IDENTIFIER, DEVICE_DISPLAY_NAME

  @api_version = [2, 0, 4]

  @response_expected[FUNCTION_GET_ACCELERATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_MAGNETIC_FIELD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_ANGULAR_VELOCITY] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_ALL_DATA] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_ORIENTATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_QUATERNION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_IMU_TEMPERATURE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_LEDS_ON] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_LEDS_OFF] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_ARE_LEDS_ON] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ACCELERATION_RANGE] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_ACCELERATION_RANGE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_MAGNETOMETER_RANGE] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_MAGNETOMETER_RANGE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_CONVERGENCE_SPEED] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_CONVERGENCE_SPEED] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_CALIBRATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_CALIBRATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ACCELERATION_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_ACCELERATION_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_MAGNETIC_FIELD_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_MAGNETIC_FIELD_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ANGULAR_VELOCITY_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_ANGULAR_VELOCITY_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ALL_DATA_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_ALL_DATA_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ORIENTATION_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_ORIENTATION_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_QUATERNION_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_QUATERNION_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_ORIENTATION_CALCULATION_ON] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_ORIENTATION_CALCULATION_OFF] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_IS_ORIENTATION_CALCULATION_ON] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_SPITFP_BAUDRATE_CONFIG] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_SPITFP_BAUDRATE_CONFIG] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_SEND_TIMEOUT_COUNT] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_SPITFP_BAUDRATE] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_SPITFP_BAUDRATE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_SPITFP_ERROR_COUNT] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_ENABLE_STATUS_LED] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_DISABLE_STATUS_LED] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_IS_STATUS_LED_ENABLED] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_PROTOCOL1_BRICKLET_NAME] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_CHIP_TEMPERATURE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_RESET] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_WRITE_BRICKLET_PLUGIN] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_READ_BRICKLET_PLUGIN] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_IDENTITY] = RESPONSE_EXPECTED_ALWAYS_TRUE

  @callback_formats[CALLBACK_ACCELERATION] = [14, 's s s']
  @callback_formats[CALLBACK_MAGNETIC_FIELD] = [14, 's s s']
  @callback_formats[CALLBACK_ANGULAR_VELOCITY] = [14, 's s s']
  @callback_formats[CALLBACK_ALL_DATA] = [28, 's s s s s s s s s s']
  @callback_formats[CALLBACK_ORIENTATION] = [14, 's s s']
  @callback_formats[CALLBACK_QUATERNION] = [24, 'e e e e']

  @ipcon.add_device self
end

Instance Method Details

#are_leds_on ⇒ Object

Returns true if the orientation and direction LEDs of the IMU Brick are on, false otherwise.



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# File 'lib/tinkerforge/brick_imu.rb', line 310

def are_leds_on
  check_validity

  send_request FUNCTION_ARE_LEDS_ON, [], '', 9, '?'
end

#disable_status_led ⇒ Object

Disables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

.. versionadded

2.3.1$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 677

def disable_status_led
  check_validity

  send_request FUNCTION_DISABLE_STATUS_LED, [], '', 8, ''
end

#enable_status_led ⇒ Object

Enables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

.. versionadded

2.3.1$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 663

def enable_status_led
  check_validity

  send_request FUNCTION_ENABLE_STATUS_LED, [], '', 8, ''
end

#get_acceleration ⇒ Object

Returns the calibrated acceleration from the accelerometer for the x, y and z axis.

If you want to get the acceleration periodically, it is recommended to use the CALLBACK_ACCELERATION callback and set the period with BrickIMU#set_acceleration_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 189

def get_acceleration
  check_validity

  send_request FUNCTION_GET_ACCELERATION, [], '', 14, 's s s'
end

#get_acceleration_period ⇒ Object

Returns the period as set by BrickIMU#set_acceleration_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 436

def get_acceleration_period
  check_validity

  send_request FUNCTION_GET_ACCELERATION_PERIOD, [], '', 12, 'L'
end

#get_acceleration_range ⇒ Object

Not implemented yet.



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# File 'lib/tinkerforge/brick_imu.rb', line 324

def get_acceleration_range
  check_validity

  send_request FUNCTION_GET_ACCELERATION_RANGE, [], '', 9, 'C'
end

#get_all_data ⇒ Object

Returns the data from BrickIMU#get_acceleration, BrickIMU#get_magnetic_field and BrickIMU#get_angular_velocity as well as the temperature of the IMU Brick.

If you want to get the data periodically, it is recommended to use the CALLBACK_ALL_DATA callback and set the period with BrickIMU#set_all_data_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 226

def get_all_data
  check_validity

  send_request FUNCTION_GET_ALL_DATA, [], '', 28, 's s s s s s s s s s'
end

#get_all_data_period ⇒ Object

Returns the period as set by BrickIMU#set_all_data_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 481

def get_all_data_period
  check_validity

  send_request FUNCTION_GET_ALL_DATA_PERIOD, [], '', 12, 'L'
end

#get_angular_velocity ⇒ Object

Returns the calibrated angular velocity from the gyroscope for the x, y and z axis in °/14.375s (you have to divide by 14.375 to get the value in °/s).

If you want to get the angular velocity periodically, it is recommended to use the CALLBACK_ANGULAR_VELOCITY callback and set the period with BrickIMU#set_angular_velocity_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 214

def get_angular_velocity
  check_validity

  send_request FUNCTION_GET_ANGULAR_VELOCITY, [], '', 14, 's s s'
end

#get_angular_velocity_period ⇒ Object

Returns the period as set by BrickIMU#set_angular_velocity_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 466

def get_angular_velocity_period
  check_validity

  send_request FUNCTION_GET_ANGULAR_VELOCITY_PERIOD, [], '', 12, 'L'
end

#get_calibration(typ) ⇒ Object

Returns the calibration for a given type as set by BrickIMU#set_calibration.



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# File 'lib/tinkerforge/brick_imu.rb', line 421

def get_calibration(typ)
  check_validity

  send_request FUNCTION_GET_CALIBRATION, [typ], 'C', 28, 's10'
end

#get_chip_temperature ⇒ Object

Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has an accuracy of ±15%. Practically it is only useful as an indicator for temperature changes.



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# File 'lib/tinkerforge/brick_imu.rb', line 709

def get_chip_temperature
  check_validity

  send_request FUNCTION_GET_CHIP_TEMPERATURE, [], '', 10, 's'
end

#get_convergence_speed ⇒ Object

Returns the convergence speed as set by BrickIMU#set_convergence_speed.



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# File 'lib/tinkerforge/brick_imu.rb', line 376

def get_convergence_speed
  check_validity

  send_request FUNCTION_GET_CONVERGENCE_SPEED, [], '', 10, 'S'
end

#get_identity ⇒ Object

Returns the UID, the UID where the Brick is connected to, the position, the hardware and firmware version as well as the device identifier.

The position is the position in the stack from ‘0’ (bottom) to ‘8’ (top).

The device identifier numbers can be found :ref:‘here <device_identifier>`. |device_identifier_constant|



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# File 'lib/tinkerforge/brick_imu.rb', line 757

def get_identity
  send_request FUNCTION_GET_IDENTITY, [], '', 33, 'Z8 Z8 k C3 C3 S'
end

#get_imu_temperature ⇒ Object

Returns the temperature of the IMU Brick.



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# File 'lib/tinkerforge/brick_imu.rb', line 288

def get_imu_temperature
  check_validity

  send_request FUNCTION_GET_IMU_TEMPERATURE, [], '', 10, 's'
end

#get_magnetic_field ⇒ Object

Returns the calibrated magnetic field from the magnetometer for the x, y and z axis.

If you want to get the magnetic field periodically, it is recommended to use the CALLBACK_MAGNETIC_FIELD callback and set the period with BrickIMU#set_magnetic_field_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 201

def get_magnetic_field
  check_validity

  send_request FUNCTION_GET_MAGNETIC_FIELD, [], '', 14, 's s s'
end

#get_magnetic_field_period ⇒ Object

Returns the period as set by BrickIMU#set_magnetic_field_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 451

def get_magnetic_field_period
  check_validity

  send_request FUNCTION_GET_MAGNETIC_FIELD_PERIOD, [], '', 12, 'L'
end

#get_magnetometer_range ⇒ Object

Not implemented yet.



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# File 'lib/tinkerforge/brick_imu.rb', line 338

def get_magnetometer_range
  check_validity

  send_request FUNCTION_GET_MAGNETOMETER_RANGE, [], '', 9, 'C'
end

#get_orientation ⇒ Object

Returns the current orientation (roll, pitch, yaw) of the IMU Brick as Euler angles. Note that Euler angles always experience a ‘gimbal lock <en.wikipedia.org/wiki/Gimbal_lock>`__.

We recommend that you use quaternions instead.

The order to sequence in which the orientation values should be applied is roll, yaw, pitch.

If you want to get the orientation periodically, it is recommended to use the CALLBACK_ORIENTATION callback and set the period with BrickIMU#set_orientation_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 244

def get_orientation
  check_validity

  send_request FUNCTION_GET_ORIENTATION, [], '', 14, 's s s'
end

#get_orientation_period ⇒ Object

Returns the period as set by BrickIMU#set_orientation_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 496

def get_orientation_period
  check_validity

  send_request FUNCTION_GET_ORIENTATION_PERIOD, [], '', 12, 'L'
end

#get_protocol1_bricklet_name(port) ⇒ Object

Returns the firmware and protocol version and the name of the Bricklet for a given port.

This functions sole purpose is to allow automatic flashing of v1.x.y Bricklet plugins.



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# File 'lib/tinkerforge/brick_imu.rb', line 697

def get_protocol1_bricklet_name(port)
  check_validity

  send_request FUNCTION_GET_PROTOCOL1_BRICKLET_NAME, [port], 'k', 52, 'C C3 Z40'
end

#get_quaternion ⇒ Object

Returns the current orientation (x, y, z, w) of the IMU as ‘quaternions <en.wikipedia.org/wiki/Quaternions_and_spatial_rotation>`__.

You can go from quaternions to Euler angles with the following formula

xAngle = atan2(2*y*w - 2*x*z, 1 - 2*y*y - 2*z*z) yAngle = atan2(2*x*w - 2*y*z, 1 - 2*x*x - 2*z*z) zAngle = asin(2*x*y + 2*z*w)

This process is not reversible, because of the ‘gimbal lock <en.wikipedia.org/wiki/Gimbal_lock>`__.

It is also possible to calculate independent angles. You can calculate yaw, pitch and roll in a right-handed vehicle coordinate system according to

DIN70000 with

yaw = atan2(2*x*y + 2*w*z, w*w + x*x - y*y - z*z) pitch = -asin(2*w*y - 2*x*z) roll = -atan2(2*y*z + 2*w*x, -w*w + x*x + y*y - z*z))

Converting the quaternions to an OpenGL transformation matrix is

possible with the following formula

matrix = [[1 - 2*(y*y + z*z), 2*(x*y - w*z), 2*(x*z + w*y), 0],

[    2*(x*y + w*z), 1 - 2*(x*x + z*z),     2*(y*z - w*x), 0],
[    2*(x*z - w*y),     2*(y*z + w*x), 1 - 2*(x*x + y*y), 0],
[                0,                 0,                 0, 1]]

If you want to get the quaternions periodically, it is recommended to use the CALLBACK_QUATERNION callback and set the period with BrickIMU#set_quaternion_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 281

def get_quaternion
  check_validity

  send_request FUNCTION_GET_QUATERNION, [], '', 24, 'e e e e'
end

#get_quaternion_period ⇒ Object

Returns the period as set by BrickIMU#set_quaternion_period.



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# File 'lib/tinkerforge/brick_imu.rb', line 511

def get_quaternion_period
  check_validity

  send_request FUNCTION_GET_QUATERNION_PERIOD, [], '', 12, 'L'
end

#get_send_timeout_count(communication_method) ⇒ Object

Returns the timeout count for the different communication methods.

The methods 0-2 are available for all Bricks, 3-7 only for Master Bricks.

This function is mostly used for debugging during development, in normal operation the counters should nearly always stay at 0.

.. versionadded

2.3.3$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 600

def get_send_timeout_count(communication_method)
  check_validity

  send_request FUNCTION_GET_SEND_TIMEOUT_COUNT, [communication_method], 'C', 12, 'L'
end

#get_spitfp_baudrate(bricklet_port) ⇒ Object

Returns the baudrate for a given Bricklet port, see BrickIMU#set_spitfp_baudrate.

.. versionadded

2.3.3$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 630

def get_spitfp_baudrate(bricklet_port)
  check_validity

  send_request FUNCTION_GET_SPITFP_BAUDRATE, [bricklet_port], 'k', 12, 'L'
end

#get_spitfp_baudrate_config ⇒ Object

Returns the baudrate config, see BrickIMU#set_spitfp_baudrate_config.

.. versionadded

2.3.5$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 586

def get_spitfp_baudrate_config
  check_validity

  send_request FUNCTION_GET_SPITFP_BAUDRATE_CONFIG, [], '', 13, '? L'
end

#get_spitfp_error_count(bricklet_port) ⇒ Object

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,

  • message checksum errors,

  • framing errors and

  • overflow errors.

The errors counts are for errors that occur on the Brick side. All Bricklets have a similar function that returns the errors on the Bricklet side.

.. versionadded

2.3.3$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 649

def get_spitfp_error_count(bricklet_port)
  check_validity

  send_request FUNCTION_GET_SPITFP_ERROR_COUNT, [bricklet_port], 'k', 24, 'L L L L'
end

#is_orientation_calculation_on ⇒ Object

Returns true if the orientation calculation of the IMU Brick is on, false otherwise.

.. versionadded

2.0.2$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 551

def is_orientation_calculation_on
  check_validity

  send_request FUNCTION_IS_ORIENTATION_CALCULATION_ON, [], '', 9, '?'
end

#is_status_led_enabled ⇒ Object

Returns true if the status LED is enabled, false otherwise.

.. versionadded

2.3.1$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 686

def is_status_led_enabled
  check_validity

  send_request FUNCTION_IS_STATUS_LED_ENABLED, [], '', 9, '?'
end

#leds_off ⇒ Object

Turns the orientation and direction LEDs of the IMU Brick off.



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# File 'lib/tinkerforge/brick_imu.rb', line 302

def leds_off
  check_validity

  send_request FUNCTION_LEDS_OFF, [], '', 8, ''
end

#leds_on ⇒ Object

Turns the orientation and direction LEDs of the IMU Brick on.



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# File 'lib/tinkerforge/brick_imu.rb', line 295

def leds_on
  check_validity

  send_request FUNCTION_LEDS_ON, [], '', 8, ''
end

#orientation_calculation_off ⇒ Object

Turns the orientation calculation of the IMU Brick off.

If the calculation is off, BrickIMU#get_orientation will return the last calculated value until the calculation is turned on again.

The trigonometric functions that are needed to calculate the orientation are very expensive. We recommend to turn the orientation calculation off if the orientation is not needed, to free calculation time for the sensor fusion algorithm.

As default the calculation is on.

.. versionadded

2.0.2$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 541

def orientation_calculation_off
  check_validity

  send_request FUNCTION_ORIENTATION_CALCULATION_OFF, [], '', 8, ''
end

#orientation_calculation_on ⇒ Object

Turns the orientation calculation of the IMU Brick on.

As default the calculation is on.

.. versionadded

2.0.2$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 522

def orientation_calculation_on
  check_validity

  send_request FUNCTION_ORIENTATION_CALCULATION_ON, [], '', 8, ''
end

#read_bricklet_plugin(port, offset) ⇒ Object

Reads 32 bytes of firmware from the bricklet attached at the given port. The bytes are read starting at the position offset * 32.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.



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# File 'lib/tinkerforge/brick_imu.rb', line 743

def read_bricklet_plugin(port, offset)
  check_validity

  send_request FUNCTION_READ_BRICKLET_PLUGIN, [port, offset], 'k C', 40, 'C32'
end

#register_callback(id, &block) ⇒ Object

Registers a callback with ID id to the block block.



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# File 'lib/tinkerforge/brick_imu.rb', line 762

def register_callback(id, &block)
  callback = block
  @registered_callbacks[id] = callback
end

#reset ⇒ Object

Calling this function will reset the Brick. Calling this function on a Brick inside of a stack will reset the whole stack.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!



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# File 'lib/tinkerforge/brick_imu.rb', line 721

def reset
  check_validity

  send_request FUNCTION_RESET, [], '', 8, ''
end

#set_acceleration_period(period) ⇒ Object

Sets the period with which the CALLBACK_ACCELERATION callback is triggered periodically. A value of 0 turns the callback off.



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# File 'lib/tinkerforge/brick_imu.rb', line 429

def set_acceleration_period(period)
  check_validity

  send_request FUNCTION_SET_ACCELERATION_PERIOD, [period], 'L', 8, ''
end

#set_acceleration_range(range) ⇒ Object

Not implemented yet.



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# File 'lib/tinkerforge/brick_imu.rb', line 317

def set_acceleration_range(range)
  check_validity

  send_request FUNCTION_SET_ACCELERATION_RANGE, [range], 'C', 8, ''
end

#set_all_data_period(period) ⇒ Object

Sets the period with which the CALLBACK_ALL_DATA callback is triggered periodically. A value of 0 turns the callback off.



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# File 'lib/tinkerforge/brick_imu.rb', line 474

def set_all_data_period(period)
  check_validity

  send_request FUNCTION_SET_ALL_DATA_PERIOD, [period], 'L', 8, ''
end

#set_angular_velocity_period(period) ⇒ Object

Sets the period with which the CALLBACK_ANGULAR_VELOCITY callback is triggered periodically. A value of 0 turns the callback off.



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# File 'lib/tinkerforge/brick_imu.rb', line 459

def set_angular_velocity_period(period)
  check_validity

  send_request FUNCTION_SET_ANGULAR_VELOCITY_PERIOD, [period], 'L', 8, ''
end

#set_calibration(typ, data) ⇒ Object

There are several different types that can be calibrated:

"Type", "Description", "Values"

"0",    "Accelerometer Gain", "``[mul x, mul y, mul z, div x, div y, div z, 0, 0, 0, 0]``"
"1",    "Accelerometer Bias", "``[bias x, bias y, bias z, 0, 0, 0, 0, 0, 0, 0]``"
"2",    "Magnetometer Gain",  "``[mul x, mul y, mul z, div x, div y, div z, 0, 0, 0, 0]``"
"3",    "Magnetometer Bias",  "``[bias x, bias y, bias z, 0, 0, 0, 0, 0, 0, 0]``"
"4",    "Gyroscope Gain",     "``[mul x, mul y, mul z, div x, div y, div z, 0, 0, 0, 0]``"
"5",    "Gyroscope Bias",     "``[bias xl, bias yl, bias zl, temp l, bias xh, bias yh, bias zh, temp h, 0, 0]``"
The calibration via gain and bias is done with the following formula

new_value = (bias + orig_value) * gain_mul / gain_div

If you really want to write your own calibration software, please keep in mind that you first have to undo the old calibration (set bias to 0 and gain to 1/1) and that you have to average over several thousand values to obtain a usable result in the end.

The gyroscope bias is highly dependent on the temperature, so you have to calibrate the bias two times with different temperatures. The values “xl“, “yl“, “zl“ and “temp l“ are the bias for “x“, “y“, “z“ and the corresponding temperature for a low temperature. The values “xh“, “yh“, “zh“ and “temp h“ are the same for a high temperatures. The temperature difference should be at least 5°C. If you have a temperature where the IMU Brick is mostly used, you should use this temperature for one of the sampling points.

.. note

We highly recommend that you use the Brick Viewer to calibrate your IMU Brick.



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# File 'lib/tinkerforge/brick_imu.rb', line 414

def set_calibration(typ, data)
  check_validity

  send_request FUNCTION_SET_CALIBRATION, [typ, data], 'C s10', 8, ''
end

#set_convergence_speed(speed) ⇒ Object

Sets the convergence speed of the IMU Brick. The convergence speed determines how the different sensor measurements are fused.

If the orientation of the IMU Brick is off by 10° and the convergence speed is set to 20°/s, it will take 0.5s until the orientation is corrected. However, if the correct orientation is reached and the convergence speed is too high, the orientation will fluctuate with the fluctuations of the accelerometer and the magnetometer.

If you set the convergence speed to 0, practically only the gyroscope is used to calculate the orientation. This gives very smooth movements, but errors of the gyroscope will not be corrected. If you set the convergence speed to something above 500, practically only the magnetometer and the accelerometer are used to calculate the orientation. In this case the movements are abrupt and the values will fluctuate, but there won’t be any errors that accumulate over time.

In an application with high angular velocities, we recommend a high convergence speed, so the errors of the gyroscope can be corrected fast. In applications with only slow movements we recommend a low convergence speed. You can change the convergence speed on the fly. So it is possible (and recommended) to increase the convergence speed before an abrupt movement and decrease it afterwards again.

You might want to play around with the convergence speed in the Brick Viewer to get a feeling for a good value for your application.



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# File 'lib/tinkerforge/brick_imu.rb', line 369

def set_convergence_speed(speed)
  check_validity

  send_request FUNCTION_SET_CONVERGENCE_SPEED, [speed], 'S', 8, ''
end

#set_magnetic_field_period(period) ⇒ Object

Sets the period with which the CALLBACK_MAGNETIC_FIELD callback is triggered periodically. A value of 0 turns the callback off.



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# File 'lib/tinkerforge/brick_imu.rb', line 444

def set_magnetic_field_period(period)
  check_validity

  send_request FUNCTION_SET_MAGNETIC_FIELD_PERIOD, [period], 'L', 8, ''
end

#set_magnetometer_range(range) ⇒ Object

Not implemented yet.



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# File 'lib/tinkerforge/brick_imu.rb', line 331

def set_magnetometer_range(range)
  check_validity

  send_request FUNCTION_SET_MAGNETOMETER_RANGE, [range], 'C', 8, ''
end

#set_orientation_period(period) ⇒ Object

Sets the period with which the CALLBACK_ORIENTATION callback is triggered periodically. A value of 0 turns the callback off.



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# File 'lib/tinkerforge/brick_imu.rb', line 489

def set_orientation_period(period)
  check_validity

  send_request FUNCTION_SET_ORIENTATION_PERIOD, [period], 'L', 8, ''
end

#set_quaternion_period(period) ⇒ Object

Sets the period with which the CALLBACK_QUATERNION callback is triggered periodically. A value of 0 turns the callback off.



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# File 'lib/tinkerforge/brick_imu.rb', line 504

def set_quaternion_period(period)
  check_validity

  send_request FUNCTION_SET_QUATERNION_PERIOD, [period], 'L', 8, ''
end

#set_spitfp_baudrate(bricklet_port, baudrate) ⇒ Object

Sets the baudrate for a specific Bricklet port.

If you want to increase the throughput of Bricklets you can increase the baudrate. If you get a high error count because of high interference (see BrickIMU#get_spitfp_error_count) you can decrease the baudrate.

If the dynamic baudrate feature is enabled, the baudrate set by this function corresponds to the maximum baudrate (see BrickIMU#set_spitfp_baudrate_config).

Regulatory testing is done with the default baudrate. If CE compatibility or similar is necessary in your applications we recommend to not change the baudrate.

.. versionadded

2.3.3$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 621

def set_spitfp_baudrate(bricklet_port, baudrate)
  check_validity

  send_request FUNCTION_SET_SPITFP_BAUDRATE, [bricklet_port, baudrate], 'k L', 8, ''
end

#set_spitfp_baudrate_config(enable_dynamic_baudrate, minimum_dynamic_baudrate) ⇒ Object

The SPITF protocol can be used with a dynamic baudrate. If the dynamic baudrate is enabled, the Brick will try to adapt the baudrate for the communication between Bricks and Bricklets according to the amount of data that is transferred.

The baudrate will be increased exponentially if lots of data is sent/received and decreased linearly if little data is sent/received.

This lowers the baudrate in applications where little data is transferred (e.g. a weather station) and increases the robustness. If there is lots of data to transfer (e.g. Thermal Imaging Bricklet) it automatically increases the baudrate as needed.

In cases where some data has to transferred as fast as possible every few seconds (e.g. RS485 Bricklet with a high baudrate but small payload) you may want to turn the dynamic baudrate off to get the highest possible performance.

The maximum value of the baudrate can be set per port with the function BrickIMU#set_spitfp_baudrate. If the dynamic baudrate is disabled, the baudrate as set by BrickIMU#set_spitfp_baudrate will be used statically.

.. versionadded

2.3.5$nbsp;(Firmware)



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# File 'lib/tinkerforge/brick_imu.rb', line 577

def set_spitfp_baudrate_config(enable_dynamic_baudrate, minimum_dynamic_baudrate)
  check_validity

  send_request FUNCTION_SET_SPITFP_BAUDRATE_CONFIG, [enable_dynamic_baudrate, minimum_dynamic_baudrate], '? L', 8, ''
end

#write_bricklet_plugin(port, offset, chunk) ⇒ Object

Writes 32 bytes of firmware to the bricklet attached at the given port. The bytes are written to the position offset * 32.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.



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# File 'lib/tinkerforge/brick_imu.rb', line 732

def write_bricklet_plugin(port, offset, chunk)
  check_validity

  send_request FUNCTION_WRITE_BRICKLET_PLUGIN, [port, offset, chunk], 'k C C32', 8, ''
end