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ATTACH_ANALOG_INPUT_ACCELEROMETER

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Attach channel(s) to a task to measure acceleration using an accelerometer. **Compatibility:** Compatible with National Instruments devices that utilize NI-DAQmx. Tested with a simulated NI-9234 module. This block is designed for use with Windows and Linux systems due to NI driver availability. Ensure you have installed the NI-DAQmx runtime from https://www.ni.com/en/support/downloads/drivers/download.ni-daq-mx.html. Params: task_name : str The name of the task to attach the channel(s) to. cDAQ_start_channel : NIDAQmxDevice The device and channel to read from. cDAQ_end_channel : NIDAQmxDevice To read from only one channel, set this to the same as `cDAQ_start_channel`. To read from multiple channels, set this to the last channel you want to read from. min_val : float Specifies in **units** the minimum value you expect to measure (default is -5.0). max_val : float Specifies in **units** the maximum value you expect to measure (default is 5.0). units : Literal The units to use to return accelerometer measurements (default is "G"). sensitivity : float The sensitivity of the sensor. This value is in the units you specify with the `sensitivity_units` input. Refer to the sensor documentation to determine this value (default is 1000.0). sensitivity_units : Literal Specifies the units of the sensitivity input (default is "Millivolts per G"). current_excitation_source : Literal Specifies the source of excitation (default is "Internal"). current_excitation_value : float Specifies in amperes the amount of excitation to supply to the sensor. Refer to the sensor documentation to determine this value (default is 0.004). Returns: out : Optional[DataContainer] This block does not return any meaningful data; it is designed for creating a task to measure acceleration using an accelerometer.
Python Code
from flojoy import flojoy, DataContainer, NIDAQmxDevice, DeviceConnectionManager
from typing import Optional, Literal
import nidaqmx


@flojoy(deps={"nidaqmx": "0.9.0"})
def ATTACH_ANALOG_INPUT_ACCELEROMETER(
    task_name: str,
    cDAQ_start_channel: NIDAQmxDevice,
    cDAQ_end_channel: NIDAQmxDevice,
    min_val: float = -5.0,
    max_val: float = 5.0,
    units: Literal["G", "Inches per second squared", "Meters per second squared"] = "G",
    sensitivity: float = 1000.0,
    sensitivity_units: Literal["Millivolts per G" "Volts per G"] = "Millivolts per G",
    current_excitation_source: Literal["External", "Internal", "None"] = "Internal",
    current_excitation_value: float = 0.004,
    default: Optional[DataContainer] = None,
) -> Optional[DataContainer]:
    """Attach channel(s) to a task to measure acceleration using an accelerometer.

    **Compatibility:**
    Compatible with National Instruments devices that utilize NI-DAQmx. Tested with a simulated NI-9234 module.

    This block is designed for use with Windows and Linux systems due to NI driver availability. Ensure you have installed the NI-DAQmx runtime from https://www.ni.com/en/support/downloads/drivers/download.ni-daq-mx.html.

    Parameters
    ----------
    task_name : str
        The name of the task to attach the channel(s) to.
    cDAQ_start_channel : NIDAQmxDevice
        The device and channel to read from.
    cDAQ_end_channel : NIDAQmxDevice
        To read from only one channel, set this to the same as `cDAQ_start_channel`. To read from multiple channels, set this to the last channel you want to read from.
    min_val : float, optional
        Specifies in **units** the minimum value you expect to measure (default is -5.0).
    max_val : float, optional
        Specifies in **units** the maximum value you expect to measure (default is 5.0).
    units : Literal, optional
        The units to use to return accelerometer measurements (default is "G").
    sensitivity : float, optional
        The sensitivity of the sensor. This value is in the units you specify with the `sensitivity_units` input. Refer to the sensor documentation to determine this value (default is 1000.0).
    sensitivity_units : Literal, optional
        Specifies the units of the sensitivity input (default is "Millivolts per G").
    current_excitation_source : Literal, optional
        Specifies the source of excitation (default is "Internal").
    current_excitation_value : float, optional
        Specifies in amperes the amount of excitation to supply to the sensor. Refer to the sensor documentation to determine this value (default is 0.004).

    Returns
    -------
    Optional[DataContainer]
        This block does not return any meaningful data; it is designed for creating a task to measure acceleration using an accelerometer.

    """
    # Check if task already exists
    task = DeviceConnectionManager.get_connection(task_name).get_handle()

    # Attach the requested channel(s) to the task
    units = {
        "G": nidaqmx.constants.AccelUnits.G,
        "Inches per second squared": nidaqmx.constants.AccelUnits.INCHES_PER_SECOND_SQUARED,
        "Meters per second squared": nidaqmx.constants.AccelUnits.METERS_PER_SECOND_SQUARED,
    }[units]

    sensitivity_units = {
        "Millivolts per G": nidaqmx.constants.AccelSensitivityUnits.MILLIVOLTS_PER_G,
        "Volts per G": nidaqmx.constants.AccelSensitivityUnits.VOLTS_PER_G,
    }[sensitivity_units]

    current_excitation_source = {
        "External": nidaqmx.constants.ExcitationSource.EXTERNAL,
        "Internal": nidaqmx.constants.ExcitationSource.INTERNAL,
        "None": nidaqmx.constants.ExcitationSource.NONE,
    }[current_excitation_source]

    name, address = cDAQ_start_channel.get_id().split("/")
    if cDAQ_end_channel:
        _, address_end = cDAQ_end_channel.get_id().split("/")
        address = f"{address}:{address_end[2:]}"
    physical_channels = f"{name}/{address}"

    task.ai_channels.add_ai_accel_chan(
        physical_channels,
        min_val=min_val,
        max_val=max_val,
        units=units,
        sensitivity_units=sensitivity_units,
        sensitivity=sensitivity,
        current_excit_source=current_excitation_source,
        current_excit_val=current_excitation_value,
    )

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Example App

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This app shows how to use a accelerometer input block for with National Instruments Compact DAQ module.

Blocks used:

  • CREATE_TASK_ANALOG_INPUT_ACCELEROMETER
  • CONFIG_TASK_SAMPLE_CLOCK_TIMINGS
  • READ_TASK
  • LINE

The blocks were connected as shown, and the app was run. The result displayed the first 100 samples taken from the device buffer for 3 channels.