Capture to device

Note that as data is streamed over Bluetooth, external factors can cause dropped samples. If this is an issue, you can either interpolate between samples or use To Sensor mode instead, to avoid dropped samples altogether.

 Watch the Vicon video, Capture to Device on YouTube.

Summary of To device mode

To capture to a device:

1. Open the Capture.U app.
2. In the Capture section tap To Device.

3. Add a new Session or select an existing one (see Capture to sensor, Step 3).
   Important: If you plan to capture global angles, before you start capture, you must calibrate the IMU sensors. For instructions on how to do this, see Calibrate IMUs.

4. Create a New Trial (see Capture to sensor, Step 4, but note that the capture options differ, as shown in the preceding table).

5. Select the data you wish to capture.
   You also have the option to set the capture rate for the low-g accelerometer, gyroscope, and high-g accelerometer.
   Note that when Global Angles is selected, Low g Accelerometer, Gyroscope, and Magnetometer are also captured and the capture rate is reduced to 225 Hz (A, G) 70 Hz (M) for the Low g sensor.
6. Tap Start Capture at the bottom of the screen.
   

7. Select the required sensors (see Capture to sensor, Step 7).
   You have the option to name (or re-name) sensors on this screen. For instructions, see Manage sensor names. 
   If you chose to capture Global Angles, one or more of the sensors may be displayed with a 'Require calibration' icon  or a 'Calibrated' icon  at its top right. For further explanation, see the next step.

8. Tap Start Capture.
   To add notes during capture, tap Notes (top right).
   To add a region of interest, tap Start a region of interest at the top of the screen (for details, see Work with regions of interest).
   

   If you chose to capture Global Angles:

   1. If one or more of the selected sensors is displayed with a 'Require calibration' icon  at the top right, after you tap Start Capture, on the next screen, a message at the the bottom of the screen prompts you to begin calibration when the trial starts. 
      After several seconds, the capture pane is displayed. A message towards the top of the screen prompts you to calibrate the sensors. 

   2. For more information on calibration, tap the How to calibrate link or see Calibrate IMUs.

   3. When you've finished moving the sensor, after 60 seconds the sensor icon changes to 'Calibrated'  to indicate that calibration is occurring (calibration is a continuous process).

9. When you have captured the required data, tap Stop Capture.
   Your new trial is displayed in the list of trials on the right of the screen (the most recent trial is at the top).

   Notice that in the filter at the top, Device is automatically selected, to display trials recorded directly to your iOS device. If required, you can change this to display trials captured to sensors, or all trials.

    

   You can play back a recorded video on your iOS device without exiting Capture.U by tapping the video icon in the list of trials.

    

   To add notes after capturing, swipe the trial left and tap Notes.

    

10. To export your data and any video/notes, swipe the trial left and tap Export.
    If you recorded a video, you are asked if you want to include it in the export. Tap Yes, then tap the required export option.
    A .zip file containing your data (.csv), notes (.txt) and video (.mp4) is exported. 
    If you chose to capture Global Angles and export a .csv file, the CSV will include the Low g data (Low g accelerometer, gyroscope and magnetometer) and the global angles. The global angles are exported as helical angles and quaternion components (Qx, Qy, Qz, Qr).

    Tip: Use Quicktime or another suitable video player, eg VLC Media Player, to view the downloaded video file.

Export regions of interest from a device

1. On the region of interest, swipe left and tap Export.
2. Locate the .zip file that is exported.

3. To access the regions of interest data, extract all files from the .zip file.
   Two .csv files are extracted: one contains trial data and the other contains regions of interest data.