BIOPAC senstream research rings

This is a quick guide of how to use our BIOPAC senstream research rings and how to transfer the data to the AcqKnowledge software for analysis.

The BIOPAC senstream research rings captures high quality data from numerous physiological signals through a user-friendly portable device. The rings are suited for data collection in everyday settings also outside the lab.

The rings have:

  • 3 ECG electrodes, samping rate up to 800 Hz
  • 2 EDA/GSR electrodes, sampling rate up to 400 Hz
  • An optical PPG sensor, sampling rate up to 400 Hz
  • The rings can furthermore collect temperature and accelerometry data.

To collect data with a ring, you need to download the Senstream app to an apple device. COBE Lab has two iPads you can borrow if you wish.

If possible, always remember to charge the rings between participants, because they can quickly run out of battery when in use often.

This guide includes:

  1. How to prepare for data collection
  2. How to collect data
  3. How to transfer the data from the ring to the AcqKnowledge software
  4. Data management in COBE Lab

Preparing for data collection

Open the app and click on the plus in the top right corner to connect to the ring through Bluetooth. If the apple device has trouble connecting to the ring, briefly place the charger on the ring and remove it again or tap twice on the ring. This should help the device connect to the ring.

Click on the ring in the app, scroll down and click on calibrate ring before recording data. The ring status says ‘calibrating’ and switches to ‘available’ when it is finished.

If you wish to save the recorded data, you can either do so on the Senstream Cloud or locally on the apple device. You switch between these two by clicking on the cogwheel in the top right corner. Under ‘session storage’ it should either say ‘Switch to Local Files Browser’ or ‘Switch to Senstream Cloud’. We strongly recommend you save the data locally on the device.

You can adjust the size of the ring using the 8 sizing shims. The ring needs to fit snugly on the participant’s finger to capture high quality data. Any finger will work, but the inner finger upper proximal phalanges work best. Those are the finger pads that are closest to your palm on the index, middle, and ring finger. Simply slide the shim into the ring and push until it is flush. To remove the shim again, pull in the opposite direction.

Now you should be ready to collect data.

How to collect data with the BIOPAC senstream research rings

  • Either before you start the session or during you can choose which data you wish to record. Before the session you choose from the list, on the same page where to can start the session, and during the session, you click on ‘edit’ and choose from the list.
  • Under ‘session detail’ you can set a timer for the session. The session automatically ends when the timer runs out.
  • Click on ‘record session’ and ‘start’.
  • You can mark events by clicking on ‘mark event’ at the bottom of the screen, and you can see the plots of the recorded data in real time on the screen.
  • To end the session, click on ‘end session’ in the top left corner.

How to transer the data to AcqKnowledge

To analyse the data you need to transfer them to a compatible software, such as AcqKnowledge which COBE Lab has access to. AcqKnowledge offers a range of visualization and analytic tools. The steps below convert the data files to .csv files, so you can analyze your data in which ever program you prefer that reads .csv files.

Follow these steps to transfer the data to AcqKnowledge:

  1. Find the session with the recording you wish to transfer.
  2. Hold down your finger on the session until a pop up window appears and click ‘Share’.
  3. Choose which way you wish to share the data, e.g. by email or airdrop. Ideally share it to a computer with AcqKnowledge.
  4. Share the data and navigate to the data file on the device your shared it to. The name of the file depends on the name of the session in the app.
  5. The file has the file extension ‘.senstream’. Rename the file extension to ‘.zip’.
  6. Unzip the file to create a folder.
  7. Inside the folder is a folder called ‘signalFiles’ and inside that are two folders called ‘app’ and ‘Senstream #xxxx’ The Senstream folder contains all the recording data. The app folder contains the event marker data.
  8. Open AcqKnowledge and click ‘create empty graph file’. Remember that to use AcqKnowledge the iLock-key needs to be inserted into the computer.
  9. In the empty graph window click on ‘file’ and ‘open’ and choose the files you wish to open.

Now you are ready to analyze your data.

Data management

Remember to transfer the data to your personal AU-computer and store it correctly. You should never store data on COBE Lab’s computers or iPads due to risk of data theft and data breach. We routinely delete data stored on our equipment, so you are at risk of loosing your data, if you store them on our equipment.