Movesense Sampling Package

carp_movesense_package adds Movesense sensors as connected devices to a CARP Mobile Sensing (CAMS) study. While worn, the sensor streams heart rate, RR intervals, single-channel ECG, movement and taps to the phone over Bluetooth Low Energy (BLE).

The package talks to the sensor through the Movesense mobile library (MDS), which the carp_movesense_flutter plugin bundles for Android and iOS.

Features

Measure types

The package provides six measure types in the dk.cachet.carp.movesense namespace:

See Measure types for the fields, units and example data of each measure.

Known issues in version 3.1.0

TEMPERATURE collects no data, and the gyroscope and magnetometer lists of IMU hold accelerometer values. See Temperature and Motion.

Supported models

The package supports three Movesense sensors:

All three measure single-channel ECG, heart rate, RR intervals and movement. After the sensor connects, the device manager sets movesenseDeviceType to one of these values, from the hardware type that the sensor reports. The Movesense MD is a Class IIa medical device under the EU Medical Device Regulation 2017/745.

Requirements

See Installation for the platform setup.

How it works

The sensor is a connected device of the phone. The phone connects to it, subscribes to the sensor's data and stores what arrives:

flowchart LR
    Sensor["<b>Movesense sensor</b><br/>worn by the participant"] -->|BLE| Phone
    subgraph Phone["Phone app"]
        direction TB
        Manager["<b>Device manager</b><br/>connects through MDS"] --> Probes["<b>Movesense probes</b><br/>one subscription<br/>per measure"]
        Probes --> DataManager[("<b>Data manager</b><br/>stores or uploads<br/>the measurements")]
    end

• Movesense sensor: measures ECG, heart rate, movement and taps, and sends them to the phone over BLE.
• Device manager: MovesenseDeviceManager connects to the sensor through MDS, identifies its model and checks its battery.
• Movesense probes: one probe per measure subscribes to a resource on the sensor, such as Meas/HR, and turns each notification into a measurement.
• Data manager: stores or uploads the measurements, as the data endpoint of the protocol specifies.

The app connects the sensor at runtime: it asks for the Bluetooth permissions, finds the sensor and binds it to the MovesenseDevice in the protocol. See Connecting a device.

Next steps