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The following steps describe how to download a trial from the sensors where all the sensors used for collection are connected, no data is missing, and you have not yet set up one-click downloading.

For information on other scenarios, see also:

To download a trial from the sensors:

  1. Ensure your Blue Trident sensors are connected to your computer (see Connect sensors to Capture.U Desktop).
    If a red circle is displayed in the top right of the Sensors symbol, the Blue Trident sensors need a firmware update.



    Before attempting to continue, update the firmware (see Update sensor firmware).
    Note that you can't download trials that were captured with the To Sensor mode until the sensor firmware has been updated.
  2. Click Process and on the Captures tab, under Select trial to download, click Edit & download to the right of the required trial.

     

    The Process tab changes from the Captures tab to the Preview tab, showing preview data.

     

    Note the graph legend at the top right, which enables you to easily identify which curve is related to each sensor. The legend displays an entry for each of the sensors associated with the trial and indicates which color on the graph belongs to which sensor.
    An asterisk (*) is displayed when no preview is available for the sensor(s), for example, because data has been deleted from that particular sensor.

    Preview shows the Resultant acceleration, not the captured onboard data.

  3. If required, before downloading the trial, you can edit the capture to rename it, crop it, add notes, and/or change the Save location: 
    • To rename the trial, click in the Session and/or Trial fields.

       

    • To crop the trial, so that you download only the required region:
      1. Click the Crop button at the bottom right of the graph. 



      2. Select the required part of the trial by clicking on the graph then dragging over the relevant region.
        The selected region is indicated by a rectangle. If you need to adjust the size of the selected region, drag the sides of the rectangle. 
        In the following example, the selected region excludes the start and end of the trial.

         

      3. Click Apply to crop the trial.

         

        The time of the trial changes to the cropped time.



    • To add notes, click on the Notes tab (bottom left).

       

    • To choose the file type to download, select from:
      • CSV (raw data) The default setting. If your data includes global angles, they are available in the exported _lowg.csv files. They are exported as helical angles (x_deg, y_deg, z_deg) and in a quaternion matrix (qx, qy, qz, qr).
      • Aligned outputs:
        • X1D For importing captured To Sensor trials into Vicon Nexus. The X1D file consists of .imu and .system files, and is imported into Nexus. If your data includes global angles, when they are imported into Nexus, you can display them in the Graph pane.
        • CSV Exports synchronized sensor data as a CSV file, so that you can directly compare your IMU axes. For example, the Low g (16-g) accelerometer, which captures at 1125 Hz, is synchronized and aligned to the High g (200-g) accelerometer, which captures at 1600 Hz. The CSV file has the filename suffix _aligned. If your data includes global angles, they are exported as helical angles, which are represented as x_deg, y_deg, z_deg, and in a quaternion matrix, represented as qx, qy, qz, qr.
        • Output Rate The rate to which exported CSV data is aligned. Select Output Rate and enter a number between 25 and 3200 Hz. If you don't select the Output Rate, the data is aligned to the highest capture rate (ie, High g acceleration), so all data aligns to 1600 Hz.
          The output rate applies to both the aligned CSV and X1D file to align all data to this rate.

            

          For more information on setting the output rate, see Export aligned data at a specified rate.

    • To change the location for downloaded trials, click Save to.
      This displays the File Explorer, enabling you to select the required folder.

       

  4. When you have finished editing the trial, click Download to save the trial data to your computer.



    An orange progress bar indicates the download status.
    When the trial has finished downloading, the trial is labeled Downloaded and green check marks are displayed on each sensor.

     

    The trial data and any notes you created are saved in the Save to folder.



    If you chose the Aligned CSV export option, all the synchronized and aligned CSV files include _aligned on the CSV export.



    If you chose X1D export option, the X1D file is exported as .imu and system files.



    You can then load this file into Nexus.

Download a trial when some sensors are not connected

If you can't connect all the sensors that were used for collecting data because you used more sensors that you have USB ports, connect the sensors to the available USB ports. You will be able to connect the remaining sensors later.

To download a trial when some sensors are not connected:

  1. Connect sensors to the available USB ports on your computer (see Connect sensors to Capture.U Desktop).
  2. Select Process and on the Captures tab, notice that connected sensors are displayed in blue and sensors that are not connected are displayed in gray.
    This example shows a trial that was collected with two sensors, but with only one of the sensors connected.



  3. Under Select trial to download, click Edit & download to the right of the required trial.
    On the Preview tab, a message warns you that not all sensors are connected.

     

  4. Edit the trial if required (see Step 3 in Download a trial from the sensors). To ensure data formatting is consistent, any cropping of the data of the connected sensors is automatically applied when you connect the remaining sensors.
  5. When you have finished any editing, click Download.
    When the trial has been downloaded, it is labeled Partially Downloaded.



  6. Connect the remaining sensor(s) to the computer.



  7. Select the trial.
    On the Preview tab, notice that the Crop button is unavailable, to ensure the data is formatted in the same way as the previously connected sensors.
    If you cropped the trial when you connected the first set of sensors, the trial is automatically cropped in the same way as the previously connected sensors.



  8. Click Download.
    When data from all the sensors has been downloaded for the associated trial, green check marks are displayed for each sensor.

     

Download a trial when sensor data has been erased

  1. If you deleted data from one or more sensors that were used in a trial before downloading the data, when you connect the relevant sensor(s), any sensor with deleted data is displayed with a red cross on the Captures tab:



    You can still download data from the other sensors, but when you select the trial, a message warns you that some data is missing.



  2. To continue, select Download anyway.
  3. Edit the trial if required (see Step 3 in Download a trial from the sensors) and then click Download.
    When the trial has been downloaded for all sensors, on the Captures tab, you are warned that the trial has not been discovered on all the required sensors.

Download with a single click

When you have captured trials in To Sensor mode, you can download your data with a single click to a location and format you have previously chosen. You first set the required download options in the Settings tab, and then go to the Process tab and click the Download option for the required trial(s).

To specify the options for one-click download:

  • On the Settings tab, set the data export options, which will be used for one-click download. These include the Save To location and the file format options for data export (e.g. X1D and CSV).



    To change the file type to download, select from:
    • CSV The default setting
    • Aligned outputs:
      • X1D For importing captured To Sensor trials into Vicon Nexus. The X1D file consists of .imu and .system files, and is imported into Nexus.
      • CSV Exports synchronized sensor data as a CSV file, so that you can directly compare your IMU axes. For example, the Low g (16-g) accelerometer, which captures at 1125 Hz, is synchronized and aligned to the High g (200-g) accelerometer, which captures at 1600 Hz. The CSV file has the filename suffix _aligned.
      • Output Rate The rate to which exported CSV data is aligned. Select Output Rate and enter a number between 25 and 3200 Hz. If you don't select the Output Rate, the data is aligned to the highest capture rate (ie, High g acceleration), so all data aligns to 1600 Hz.
        The output rate applies to both the aligned CSV and X1D file to align all data to this rate.
        For more information on setting the output rate, see Export aligned data at a specified rate.

To select one-click download for data export:

  • On the Process tab, select the Download option for each capture To Sensor session.



    The aligned data is generated in a CSV file with the filename suffix _aligned. If you selected X1D, an X1D file is generated (consisting of .imu and .system files, which are imported into Nexus).
    Subsequent exports from this session are exported using the options you chose on the Settings tab.

When you use one-click download, you can't trim the data. If you need to trim the data, use the Edit & download option.
When you select Edit & download, the settings information is populated into the Preview pane.

Export global angles

Capture.U Desktop enables you to export global angles that you captured in To Sensor mode with the Capture.U app. Global angles are automatically included in the normal data export process.

You can export global angles data in all the usual data export formats:

  • CSV (raw data) The global angles are available in the exported _lowg.csv files. They are exported as helical angles (x_deg, y_deg, z_deg) and in a quaternion matrix (qx, qy, qz, qr).
  • Aligned Outputs (at either a specified output rate or the default rate):
    • CSV (aligned) The global angles are exported as helical angles, which are represented as x_deg, y_deg, z_deg, and in a quaternion matrix, represented as qx, qy, qz, qr.
    • X1D (for import into Nexus) When imported into Nexus, global angles can be visualized in the Graph pane and in the 3D Perspective view.

Export aligned data at a specified rate

You can choose the rate at which your aligned CSV data is exported. For example, if you specify 1000 Hz, all data exported is aligned to 1000 Hz.

You can do this in either of these ways:

or

The Output Rate applies to both aligned CSV and X1D files to align all data to this rate.

If you don't set the Output Rate, the data is aligned to the highest capture rate (ie, High g acceleration), so all data aligns to 1600 Hz.

Set the default output rate for subsequent downloads

  1. On the Settings tab, select the required export options (for example, the location, raw data (CSV), and aligned data (X1D and CSV)).
  2. Select Output Rate and in the text box, enter a value between 25 and 3200 Hz.



    The specified output rate is applied to all trials subsequently downloaded, unless you change the settings, either on the Settings tab again or via Edit & download (see Set the output rate for a single download).

Set the output rate for a single download

  1. On the Process tab, select the Edit & download option for the required trial.
    The Preview tab is displayed, showing the currently specified options for Aligned Outputs:
    • If you haven't set the default output rate (see Set the default output rate for subsequent downloads), the Aligned Output options are not selected and the Output Rate is blank.
    • If you have set the default output rate, the values you selected populate the Aligned Outputs options and you can choose to either leave them as they are or change them.
  2. Set the required export options (for example, specify the required Save to location, raw data (CSV), and aligned data (X1D and CSV)).
  3. Select Output Rate and in the text box, enter a value between 25 and 3200 Hz.



  4. Click Download to apply the specified output rate to the selected trial.

Export notes from To Sensor mode

In Capture.U Desktop, you can review, edit and export as a .txt file any notes that you made during or after capturing data in the To Sensor mode of the Capture.U app.

Notes that are written to the sensor populate the Notes tab on the Preview tab. Any notes that you add post-capture in the Capture.U app are synced to the sensor, as long as the sensor is within range. You can also export these post-capture notes from Capture.U Desktop.

Note that:

  • Changes made to the notes in Capture.U Desktop are not synced to the sensor, so they are not retained after you exit the Capture.U app.
  • You can continue to export notes directly from the Capture.U app, as previously.

To export notes from the Capture.U app:

  1. In the Capture.U app, create your note(s) during or after capture (remember that you can only add notes after capture if the sensors are still within Bluetooth range).

     

  2. In Capture.U Desktop, on the Captures tab, to the right of the trial that you want to download:
    • To download your notes without making any further changes, click Download.
      or
    • To edit the notes or make other changes to the data, click Edit & download.



      On the Preview tab, the notes you made in the Capture.U app are displayed on the Notes tab.



  3. Make any required changes, such as cropping the trial and editing the notes.



  4. When you click Download, a .txt file containing the notes is exported to the Save to location.