LabVIEW - Laser Range Finder Bricklet¶

Simple¶

Download (Example Simple.vi)

Callback¶

Download (Example Callback.vi), Download (Example Callback - Distance Callback.vi)

Threshold¶

Download (Example Threshold.vi), Download (Example Threshold - DistanceReached Callback.vi)

Graph¶

Download (Example Graph.vi), Download (Example Graph - Distance Callback.vi)

Basic Functions¶

BrickletLaserRangeFinder(uid, ipcon) → laserRangeFinder¶

Input:	uid – Type: String ipcon – Type: .NET Refnum (IPConnection)
Output:	laserRangeFinder – Type: .NET Refnum (BrickletLaserRangeFinder)

Creates an object with the unique device ID uid. This object can then be used after the IP Connection is connected.

BrickletLaserRangeFinder.GetDistance() → distance¶

Output:	distance – Type: Int32, Unit: 1 cm, Range: [0 to 4000]

Returns the measured distance.

Sensor hardware version 1 (see GetSensorHardwareVersion()) cannot measure distance and velocity at the same time. Therefore, the distance mode has to be enabled using SetMode(). Sensor hardware version 3 can measure distance and velocity at the same time. Also the laser has to be enabled, see EnableLaser().

If you want to get the distance periodically, it is recommended to use the DistanceCallback callback and set the period with SetDistanceCallbackPeriod().

BrickletLaserRangeFinder.GetVelocity() → velocity¶

Output:	velocity – Type: Int16, Unit: 1 cm/s, Range: [-12800 to 12700]

Returns the measured velocity.

Sensor hardware version 1 (see GetSensorHardwareVersion()) cannot measure distance and velocity at the same time. Therefore, the velocity mode has to be enabled using SetMode(). Sensor hardware version 3 can measure distance and velocity at the same time, but the velocity measurement only produces stables results if a fixed measurement rate (see SetConfiguration()) is configured. Also the laser has to be enabled, see EnableLaser().

If you want to get the velocity periodically, it is recommended to use the VelocityCallback callback and set the period with SetVelocityCallbackPeriod().

BrickletLaserRangeFinder.SetMode(mode)¶

Input:	mode – Type: Byte, Range: See constants, Default: 0

Note

This function is only available if you have a LIDAR-Lite sensor with hardware version 1. Use SetConfiguration() for hardware version 3. You can check the sensor hardware version using GetSensorHardwareVersion().

The LIDAR-Lite sensor (hardware version 1) has five different modes. One mode is for distance measurements and four modes are for velocity measurements with different ranges.

The following modes are available:

• 0: Distance is measured with resolution 1.0 cm and range 0-4000 cm
• 1: Velocity is measured with resolution 0.1 m/s and range is 0-12.7 m/s
• 2: Velocity is measured with resolution 0.25 m/s and range is 0-31.75 m/s
• 3: Velocity is measured with resolution 0.5 m/s and range is 0-63.5 m/s
• 4: Velocity is measured with resolution 1.0 m/s and range is 0-127 m/s

The following constants are available for this function:

For mode:

• BrickletLaserRangeFinder.MODE_DISTANCE = 0
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_13MS = 1
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_32MS = 2
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_64MS = 3
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_127MS = 4

BrickletLaserRangeFinder.GetMode() → mode¶

Output:	mode – Type: Byte, Range: See constants, Default: 0

Returns the mode as set by SetMode().

The following constants are available for this function:

For mode:

• BrickletLaserRangeFinder.MODE_DISTANCE = 0
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_13MS = 1
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_32MS = 2
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_64MS = 3
• BrickletLaserRangeFinder.MODE_VELOCITY_MAX_127MS = 4

BrickletLaserRangeFinder.EnableLaser()¶

Activates the laser of the LIDAR.

We recommend that you wait 250ms after enabling the laser before the first call of GetDistance() to ensure stable measurements.

BrickletLaserRangeFinder.DisableLaser()¶

Deactivates the laser of the LIDAR.

BrickletLaserRangeFinder.IsLaserEnabled() → laserEnabled¶

Output:	laserEnabled – Type: Boolean

Returns true if the laser is enabled, false otherwise.

BrickletLaserRangeFinder.SetConfiguration(acquisitionCount, enableQuickTermination, thresholdValue, measurementFrequency)¶

Input:	acquisitionCount – Type: Byte, Range: [1 to 255], Default: 128 enableQuickTermination – Type: Boolean, Default: F thresholdValue – Type: Byte, Range: [0 to 255], Default: 0 measurementFrequency – Type: Int32, Unit: 1 Hz, Range: [0, 10 to 500], Default: 0

Note

This function is only available if you have a LIDAR-Lite sensor with hardware version 3. Use SetMode() for hardware version 1. You can check the sensor hardware version using GetSensorHardwareVersion().

The Acquisition Count defines the number of times the Laser Range Finder Bricklet will integrate acquisitions to find a correlation record peak. With a higher count, the Bricklet can measure longer distances. With a lower count, the rate increases. The allowed values are 1-255.

If you set Enable Quick Termination to true, the distance measurement will be terminated early if a high peak was already detected. This means that a higher measurement rate can be achieved and long distances can be measured at the same time. However, the chance of false-positive distance measurements increases.

Normally the distance is calculated with a detection algorithm that uses peak value, signal strength and noise. You can however also define a fixed Threshold Value. Set this to a low value if you want to measure the distance to something that has very little reflection (e.g. glass) and set it to a high value if you want to measure the distance to something with a very high reflection (e.g. mirror). Set this to 0 to use the default algorithm. The other allowed values are 1-255.

Set the Measurement Frequency to force a fixed measurement rate. If set to 0, the Laser Range Finder Bricklet will use the optimal frequency according to the other configurations and the actual measured distance. Since the rate is not fixed in this case, the velocity measurement is not stable. For a stable velocity measurement you should set a fixed measurement frequency. The lower the frequency, the higher is the resolution of the calculated velocity. The allowed values are 10Hz-500Hz (and 0 to turn the fixed frequency off).

New in version 2.0.3 (Plugin).

BrickletLaserRangeFinder.GetConfiguration() → acquisitionCount, enableQuickTermination, thresholdValue, measurementFrequency¶

Output:	acquisitionCount – Type: Byte, Range: [1 to 255], Default: 128 enableQuickTermination – Type: Boolean, Default: F thresholdValue – Type: Byte, Range: [0 to 255], Default: 0 measurementFrequency – Type: Int32, Unit: 1 Hz, Range: [0, 10 to 500], Default: 0

Returns the configuration as set by SetConfiguration().

New in version 2.0.3 (Plugin).

Advanced Functions¶

BrickletLaserRangeFinder.SetMovingAverage(distanceAverageLength, velocityAverageLength)¶

Input:	distanceAverageLength – Type: Byte, Range: [0 to 30], Default: 10 velocityAverageLength – Type: Byte, Range: [0 to 30], Default: 10

Sets the length of a moving averaging for the distance and velocity.

Setting the length to 0 will turn the averaging completely off. With less averaging, there is more noise on the data.

BrickletLaserRangeFinder.GetMovingAverage() → distanceAverageLength, velocityAverageLength¶

Output:	distanceAverageLength – Type: Byte, Range: [0 to 30], Default: 10 velocityAverageLength – Type: Byte, Range: [0 to 30], Default: 10

Returns the length moving average as set by SetMovingAverage().

BrickletLaserRangeFinder.GetSensorHardwareVersion() → version¶

Output:	version – Type: Byte, Range: See constants

Returns the LIDAR-Lite hardware version.

The following constants are available for this function:

For version:

• BrickletLaserRangeFinder.VERSION_1 = 1
• BrickletLaserRangeFinder.VERSION_3 = 3

New in version 2.0.3 (Plugin).

BrickletLaserRangeFinder.GetIdentity() → uid, connectedUid, position, hardwareVersion, firmwareVersion, deviceIdentifier¶

Output:

uid – Type: String, Length: up to 8 connectedUid – Type: String, Length: up to 8 position – Type: Char, Range: ["a" to "h", "z"] hardwareVersion – Type: Byte[3] 0: major – Type: Byte, Range: [0 to 255] 1: minor – Type: Byte, Range: [0 to 255] 2: revision – Type: Byte, Range: [0 to 255] firmwareVersion – Type: Byte[3] 0: major – Type: Byte, Range: [0 to 255] 1: minor – Type: Byte, Range: [0 to 255] 2: revision – Type: Byte, Range: [0 to 255] deviceIdentifier – Type: Int32, Range: [0 to 216 - 1]

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

The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions¶

BrickletLaserRangeFinder.SetDistanceCallbackPeriod(period)¶

Input:	period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

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

The DistanceCallback callback is only triggered if the distance value has changed since the last triggering.

BrickletLaserRangeFinder.GetDistanceCallbackPeriod() → period¶

Output:	period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by SetDistanceCallbackPeriod().

BrickletLaserRangeFinder.SetVelocityCallbackPeriod(period)¶

Input:	period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

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

The VelocityCallback callback is only triggered if the velocity value has changed since the last triggering.

BrickletLaserRangeFinder.GetVelocityCallbackPeriod() → period¶

Output:	period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by SetVelocityCallbackPeriod().

BrickletLaserRangeFinder.SetDistanceCallbackThreshold(option, min, max)¶

Input:	option – Type: Char, Range: See constants, Default: "x" min – Type: Int32, Unit: 1 cm, Range: [0 to 216 - 1], Default: 0 max – Type: Int32, Unit: 1 cm, Range: [0 to 216 - 1], Default: 0

Sets the thresholds for the DistanceReachedCallback callback.

The following options are possible:

Option	Description
'x'	Callback is turned off
'o'	Callback is triggered when the distance value is outside the min and max values
'i'	Callback is triggered when the distance value is inside the min and max values
'<'	Callback is triggered when the distance value is smaller than the min value (max is ignored)
'>'	Callback is triggered when the distance value is greater than the min value (max is ignored)

The following constants are available for this function:

For option:

• BrickletLaserRangeFinder.THRESHOLD_OPTION_OFF = "x"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_OUTSIDE = "o"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_INSIDE = "i"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_SMALLER = "<"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_GREATER = ">"

BrickletLaserRangeFinder.GetDistanceCallbackThreshold() → option, min, max¶

Output:	option – Type: Char, Range: See constants, Default: "x" min – Type: Int32, Unit: 1 cm, Range: [0 to 216 - 1], Default: 0 max – Type: Int32, Unit: 1 cm, Range: [0 to 216 - 1], Default: 0

Returns the threshold as set by SetDistanceCallbackThreshold().

The following constants are available for this function:

For option:

• BrickletLaserRangeFinder.THRESHOLD_OPTION_OFF = "x"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_OUTSIDE = "o"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_INSIDE = "i"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_SMALLER = "<"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_GREATER = ">"

BrickletLaserRangeFinder.SetVelocityCallbackThreshold(option, min, max)¶

Input:	option – Type: Char, Range: See constants, Default: "x" min – Type: Int16, Unit: 1 cm/s, Range: [-215 to 215 - 1], Default: 0 max – Type: Int16, Unit: 1 cm/s, Range: [-215 to 215 - 1], Default: 0

Sets the thresholds for the VelocityReachedCallback callback.

The following options are possible:

Option	Description
'x'	Callback is turned off
'o'	Callback is triggered when the velocity is outside the min and max values
'i'	Callback is triggered when the velocity is inside the min and max values
'<'	Callback is triggered when the velocity is smaller than the min value (max is ignored)
'>'	Callback is triggered when the velocity is greater than the min value (max is ignored)

The following constants are available for this function:

For option:

• BrickletLaserRangeFinder.THRESHOLD_OPTION_OFF = "x"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_OUTSIDE = "o"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_INSIDE = "i"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_SMALLER = "<"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_GREATER = ">"

BrickletLaserRangeFinder.GetVelocityCallbackThreshold() → option, min, max¶

Output:	option – Type: Char, Range: See constants, Default: "x" min – Type: Int16, Unit: 1 cm/s, Range: [-215 to 215 - 1], Default: 0 max – Type: Int16, Unit: 1 cm/s, Range: [-215 to 215 - 1], Default: 0

Returns the threshold as set by SetVelocityCallbackThreshold().

The following constants are available for this function:

For option:

• BrickletLaserRangeFinder.THRESHOLD_OPTION_OFF = "x"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_OUTSIDE = "o"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_INSIDE = "i"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_SMALLER = "<"
• BrickletLaserRangeFinder.THRESHOLD_OPTION_GREATER = ">"

BrickletLaserRangeFinder.SetDebouncePeriod(debounce)¶

Input:	debounce – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Sets the period with which the threshold callbacks

• DistanceReachedCallback,
• VelocityReachedCallback,

are triggered, if the thresholds

• SetDistanceCallbackThreshold(),
• SetVelocityCallbackThreshold(),

keep being reached.

BrickletLaserRangeFinder.GetDebouncePeriod() → debounce¶

Output:	debounce – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Returns the debounce period as set by SetDebouncePeriod().

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a function to a callback property of the device object. The available callback property and their type of parameters are described below.

event BrickletLaserRangeFinder.DistanceCallback → sender, distance¶

Callback Output:	sender – Type: .NET Refnum (BrickletLaserRangeFinder) distance – Type: Int32, Unit: 1 cm, Range: [0 to 4000]

This callback is triggered periodically with the period that is set by SetDistanceCallbackPeriod(). The parameter is the distance value of the sensor.

The DistanceCallback callback is only triggered if the distance value has changed since the last triggering.

event BrickletLaserRangeFinder.VelocityCallback → sender, velocity¶

Callback Output:	sender – Type: .NET Refnum (BrickletLaserRangeFinder) velocity – Type: Int16, Unit: 1 cm/s, Range: [-12800 to 12700]

This callback is triggered periodically with the period that is set by SetVelocityCallbackPeriod(). The parameter is the velocity value of the sensor.

The VelocityCallback callback is only triggered if the velocity has changed since the last triggering.

event BrickletLaserRangeFinder.DistanceReachedCallback → sender, distance¶

Callback Output:	sender – Type: .NET Refnum (BrickletLaserRangeFinder) distance – Type: Int32, Unit: 1 cm, Range: [0 to 4000]

This callback is triggered when the threshold as set by SetDistanceCallbackThreshold() is reached. The parameter is the distance value of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by SetDebouncePeriod().

event BrickletLaserRangeFinder.VelocityReachedCallback → sender, velocity¶

Callback Output:	sender – Type: .NET Refnum (BrickletLaserRangeFinder) velocity – Type: Int16, Unit: 1 cm/s, Range: [-12800 to 12700]

This callback is triggered when the threshold as set by SetVelocityCallbackThreshold() is reached. The parameter is the velocity value of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by SetDebouncePeriod().

Virtual Functions¶

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

BrickletLaserRangeFinder.GetAPIVersion() → apiVersion¶

Output:	apiVersion – Type: Byte[3] 0: major – Type: Byte, Range: [0 to 255] 1: minor – Type: Byte, Range: [0 to 255] 2: revision – Type: Byte, Range: [0 to 255]

Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

BrickletLaserRangeFinder.GetResponseExpected(functionId) → responseExpected¶

Input:	functionId – Type: Byte, Range: See constants
Output:	responseExpected – Type: Boolean

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by SetResponseExpected(). For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

• BrickletLaserRangeFinder.FUNCTION_SET_DISTANCE_CALLBACK_PERIOD = 3
• BrickletLaserRangeFinder.FUNCTION_SET_VELOCITY_CALLBACK_PERIOD = 5
• BrickletLaserRangeFinder.FUNCTION_SET_DISTANCE_CALLBACK_THRESHOLD = 7
• BrickletLaserRangeFinder.FUNCTION_SET_VELOCITY_CALLBACK_THRESHOLD = 9
• BrickletLaserRangeFinder.FUNCTION_SET_DEBOUNCE_PERIOD = 11
• BrickletLaserRangeFinder.FUNCTION_SET_MOVING_AVERAGE = 13
• BrickletLaserRangeFinder.FUNCTION_SET_MODE = 15
• BrickletLaserRangeFinder.FUNCTION_ENABLE_LASER = 17
• BrickletLaserRangeFinder.FUNCTION_DISABLE_LASER = 18
• BrickletLaserRangeFinder.FUNCTION_SET_CONFIGURATION = 25

BrickletLaserRangeFinder.SetResponseExpected(functionId, responseExpected)¶

Input:	functionId – Type: Byte, Range: See constants responseExpected – Type: Boolean

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

• BrickletLaserRangeFinder.FUNCTION_SET_DISTANCE_CALLBACK_PERIOD = 3
• BrickletLaserRangeFinder.FUNCTION_SET_VELOCITY_CALLBACK_PERIOD = 5
• BrickletLaserRangeFinder.FUNCTION_SET_DISTANCE_CALLBACK_THRESHOLD = 7
• BrickletLaserRangeFinder.FUNCTION_SET_VELOCITY_CALLBACK_THRESHOLD = 9
• BrickletLaserRangeFinder.FUNCTION_SET_DEBOUNCE_PERIOD = 11
• BrickletLaserRangeFinder.FUNCTION_SET_MOVING_AVERAGE = 13
• BrickletLaserRangeFinder.FUNCTION_SET_MODE = 15
• BrickletLaserRangeFinder.FUNCTION_ENABLE_LASER = 17
• BrickletLaserRangeFinder.FUNCTION_DISABLE_LASER = 18
• BrickletLaserRangeFinder.FUNCTION_SET_CONFIGURATION = 25

BrickletLaserRangeFinder.SetResponseExpectedAll(responseExpected)¶

Input:	responseExpected – Type: Boolean

Changes the response expected flag for all setter and callback configuration functions of this device at once.

Constants¶

BrickletLaserRangeFinder.DEVICE_IDENTIFIER¶

This constant is used to identify a Laser Range Finder Bricklet.

The GetIdentity() function and the IPConnection.EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

BrickletLaserRangeFinder.DEVICE_DISPLAY_NAME¶

This constant represents the human readable name of a Laser Range Finder Bricklet.