- Improved synchronization
- Synchronization is decoupled from recording
- Synchronization time is extended
- Adjustable output rates
- New filter profiles added
- Button callback
- Easy MFM
- RSSI available
- Firmware update notification in SDK
Known bugs and issues
- [iOS Version] If the iOS app crashes when connecting the sensor, please restart Bluetooth to refresh the Bluetooth services and characteristics following these steps:
- Go to Settings > Bluetooth
- Turn off Bluetooth toggle button and turn on again. Note: restarting Bluetooth in Control Center will not solve this issue since it is not a complete restart.
Turn on the Xsens DOT
Turn on the DOT sensors you want to connect by plugging in a USB cable. Once the sensors are on, you can either unplug the micro USB cable or leave it in charge while using the app. It is important that users do not try to pair Xsens DOT in the Bluetooth tab of their phone as normally done with other Bluetooth devices such as headsets. This would make the sensors undetectable for Xsens DOT App
Launch Xsens DOT APP
Launch the app and it will automatically scan for sensors. Once the app is started, wait until all your DOT sensors are detected. To start a new scan, drag the page down.
The Xsens DOT App requires the following settings to be enabled:
- Bluetooth on
- Full permission to read and write on the mobile device
If those requirements are not met when the app is started, you will receive a notification.
- Location services enabled
To connect a DOT sensor, click on the toggle switch that corresponds to the sensor you selected. When connection is established, the sensor will be highlighted and a popup message will appear at the bottom. In addition, you will be able to see the following information:
- Name Tag: Custom name tag that you can assign to each sensor
- MAC address: unique identifier for each Bluetooth device
- Battery status: battery charge percentage
- RSSI: indication of signal strength (dB). Note that this is a negative number which implies better connection strength as the absolute value decreases.
- Output rate: number of samples each second
- Filter profile: general or dynamic
By clicking on the DOT icon, you can access further details such as tag name and firmware version. If you have multiple sensors connected, it is recommended renaming them by editing the tag name to avoid connecting the sensors unintentionally.
Measure & Collect Data
Once your Xsens DOT sensors are connected, click on the “Measure & Collect” button at the bottom of the screen. Before starting to record data, it is necessary to choose the settings that best suit your applications. Follow the steps below in order to do so:
- Sensor Configuration – Output rate: Chose the output rate for your recording. Output rates from 1Hz to 60Hz are available for both Real-Time Streaming and Recording mode whereas 120Hz is only available for Recording mode.
- Sensor Configuration – Filter Profile: Choose the filter profile for your application. Use the general profile for general human motions or the dynamic profile for high-dynamic movements.
- Synchronization: Choose whether your sensors will be synchronized or not. By enabling synchronization all sensors will be aligned to a common timestamp. However, this will require a synchronization time of about 15s. This procedure is required only as a set up; after synchronization is successful it is possible to start multiple consecutive measurements.
For additional information about the various setup options, check out the Xsens DOT User Manual
After the sensors are correctly set up, two measurement modes are available:
- Real-Time Streaming (Live-mode): sensor data is streamed on the mobile phone and logged in a csv file. This Requires Bluetooth connection with the phone throughout the whole recording.
- Recording (Offline mode): sensor data is recorded in a proprietary file (not accessible from users). Data can be subsequently be exported in a csv file. This does NOT require Bluetooth connection with the phone throughout the recording.
Click on the recording mode that you want to use and press ‘Confirm’. By default, all the sensor will be selected for data recording if no other setting is changed. To change that, click on the selected tab button and uncheck the sensor you want to exclude.
Real-time Streaming will continuously stream data from the sensor to the phone and log the data in a csv file as it is being received. This requires constant Bluetooth connection between trackers and phone during the recording. Additionally, the users is required to choose between one of the following combinations of data for their recording, called “recording modes”:
- Sensor Fusion Data: data that goes through XKFCore filtering
- Orientation: Quaternion
- Orientation: Euler Angles
- Free Acceleration
- Status Inertial Data: Data coming from sensing elements (accelerometer, gyroscope, magnetometer)
- Acceleration & Angular Velocity*: available in:
- High Fidelity
- Delta quantities
- Rate quantities
- Magnetic Field
- Acceleration & Angular Velocity*: available in:
- Custom Modes: additional modes
- Euler Angles – Free Acceleration – Angular Velocity
- Euler Angles – Free Acceleration – Magnetic Field
- Quaternion – Angular Velocity
*If in doubt, it is recommended using High-Fidelity mode. This will ensure best quality data while preserving accuracy even in case of transient data loss. For further information about data output, refer to Xsens DOT User Manual.
Note: The "Default" mode featured in version v2020.0 is no longer supported.
After the chosen measurement mode is selected, click on the “START” button on the top right corner to start measurement. After a synchronization period needed to align the sensors, data charts for each sensor will be displayed. To view the graphs for multiple sensors, swipe left or right; the name tag of each sensor will be displayed in the top right corner.
It is possible to perform a heading reset during the recording by clicking on the 3 vertical dots on the top right corner. This will reset the heading of all sensors connected to zero. It is recommended doing so when all the sensors are perfectly aligned (i.e. while slotted into the Xsens DOT Charger) to avoid alignment offset.
Note that for the case of Orientation data, Euler angles will always be displayed on the app.
To stop your measurement, click on the “STOP” button on the top right corner. Sperate csv files for each sensor will be stored in:
- Android: This PC\[your Android phone]\Phone\Android\data\com.xsens.dot.android\files\logs
- iOS: Xsens DOT App folder
You can fetch your files by using 3rd-party apps that allow you to access the internal directories of your phone, such as, "Files" or any file manager app, available for both Android and iOS.
Recording will allow to start collecting data on the internal storage of Xsens DOT. A proprietary file will be stored on the sensor memory and will allow for data export through Xsens DOT App. Keep in mind that this file is not accessible for users. This mode does not require Bluetooth connection with the phone after the start trigger.
Once you have selected this mode, every connected sensor will be displayed, with its relative memory storage available and recording time. Maximum recording time for each sensor is about 88 minutes. In order to clear space on the sensor memory, press the ‘clear’ button next to each sensor or ‘clear all’ in the top right corner.
Additionally, it is possible to set a timed recording that will stop the recording automatically after a given time (clock button in the top right corner). Once you are all set, click ‘START RECORDING’ to start your recording. After a short sync, the sensors will be storing data onboard.
After the recording is started, all sensors will be displayed with the elapsed time since the beginning of the recording and the current status. To stop the recording, press the ‘STOP RECORDING’ button on the app. Notice, this requires the sensors to be within Bluetooth range with the phone. It is also possible to stop the recording by pressing holding the central button on the sensor for about 1s.
Data export via Bluetooth
After the recording is completed, click on the square button on the top right corner to move to the export interface. Here, you can select which recording files you want to export for each sensor. By default, the last recording file for each connected sensor will be selected. However, you can add or remove recording files by clicking on the chosen sensor and enable the checkbox relative to the file you are interested in.
Once your files are selected, click on the cog icon on the top right corner to select the data that you want to export. Note that free acceleration is not available in this interface in order to preserve memory; if you want to calculate it from acceleration and orientation, follow this article. Choose the combination of that is most suitable for your scenario and click on ‘confirm’. The ‘Save as Default’ button will store the selected configuration and use it as default for all following exports.
After everything is set, click on ‘Export’ to begin exporting your data. Depending on the type of connection export time may vary:
- USB cable: approximately 1/8 of the recording time
- Bluetooth connection: approximately twice the time of the recording.
Hence, it is recommended using USB cable connection with Xsens DOT Data Exporter when exporting large amount of data.
Data export via USB
You can export the recording files stored on the internal memory of Xsens DOT quickly and easily to PC with Xsens DOT Data Exporter.
- Download Xsens DOT Data Exporter for Windows or Mac.
- Extract the zipped folder and Run "Xsens DOT Data Exporter.exe"
- Connect Xsens DOT to PC via USB
- Open your browser and visit http://localhost:8181
Note that Xsens DOT Charger is not designed for USB data transmission. Use direct USB cable connection to connect Xsens DOT to PC.
Use “Scan All Ports” to scan all the sensors connected with USB cables. Note that the data export can only work with firmware 1.4.0. Previous firmware versions cannot be recoginized.
You can select the recording file by clicking the “1 File Selected >” text.
Configure the export data quantities by clicking the cog icon.
Click the export button to export the data and the recording files will be stored in your PC.
Export csv files from phone to PC
- Android: connect your phone to the PC and access the following directory: This PC\[your Android phone]\Phone\Android\data\com.xsens.dot.android\files\logs. Real-time streaming data and Recording data will be stored in the folders ‘logs’ and ‘recordings’ respectively.
- iOS: Connect your phone to your PC and Open iTunes to export the data. Once your phone is detected, click on the phone-like button on the top left corner. Then click on "File Sharing" on the left tab and select Xsens DOT app. Real-time streaming data and Recording data will be stored in the folders ‘logs’ and ‘recordings’ respectively. Click on the folder to select it and then click on "save" in the bottom right corner.
All csv files and subfolders are named in the following format: YearMonthDay_HourMinutes. To facilitate the identification of the correct measurement, enabling Details view and sort it by creation date might help.
Each file can be opened with Microsoft Excel and the content of the csv file depends on the measurement mode previously chosen. This can include the following data:
- Packet counter
- Angular velocity
- Mag data (X,Y,Z)
- Orientation (Quaternion) (W,X,Y,Z)
- Orientation (Euler angles): roll, pitch
- Free acceleration(X,Y,Z)
- Status Byte
For further information about each quantity, refer to our Xsens DOT User Manual.
App fails to install
It is possible that your processor architecture is not supported. Please refer to this Base article to check that.
Sensors are not detected
Make sure location services and Bluetooth are enabled first. Also, make sure the sensors are not paired in the Bluetooth tab of your phone.