Mobile Sensing

movisensXS has the ability to do mobile sensing. Mobile sensing is "Using the sensors of a mobile device (i.e. smartphone or tablet computer) to acquire data from the environment." Modern Smartphones are equipped with the sensors to monitor a diverse range of human activities and commonly encountered contexts.

This is particularly useful for the research field of ambulatory assessment.

Mobile sensing data is store in the Unisens format. Read more about the file format here.

WARNING

The mobile sensing features are only available on request!

Features Library version 5601

Measure the usage of e.g. chat apps to measure the social interaction time

Log App Usage Beta

This logs the used applications.

Label Description Type Default-Value
Limit to Apps Beta Applications which should be logged only. All other applications will not be written in log files. Please split with ';' if you want to specify more than one. String
Register when a user recharges the phone

Log Battery Level Beta

This logs the battery level to a unisens log.

Register whether a participant is near a setup device or other participants

Log Nearby Devices Beta

This logs nearby devices in an unsisens log file. It will send a bluetooth advertisement through IBeacon standard on supported devices and will protocol all other devices which are broadcasting with a beacon standard.

Label Description Type Default-Value
Check interval Beta Interval to check if a beacon is around in seconds. Beacon scanning consumes power, a practical value is 60 seconds. Integer 60

Log Device Running Beta

This logs device running to a unisens log.

Measure the distanced travelled or register the locations visited

Log Location Beta

This logs the location in an energy efficient way.

It uses GPS, WLAN and Cell to balance the battery usage with precision.

GPS WLAN CELL
Accuracy* ca. 10 m ca. 40 m 200 - 3000 m
Availability in erverday life 80% In cities > 70% > 90%
Time until first determination 65s 3s 2s
Requirement Clear view to the sky WLAN nearby, Internet Mobile cell tower nearby, Internet
Battery Usage High Medium Low

While tracking there are continuous location updates at a maximum rate of every 5s and every 20m. The tracking transitions to a stationary state when the participant remains within 100m of a central position of no location update occurs for 120s. The no more tracking will be done until the participajnt leaves the 100m radius.

*Location accuracy is the estimated horizontal accuracy of this location, radial, in meters. We define horizontal accuracy as the radius of 68% confidence. In other words, if you draw a circle centered at this location's latitude and longitude, and with a radius equal to the accuracy, then there is a 68% probability that the true location is inside the circle. Furthermore problems can occur with the location tracking using WLAN if the router is moving. This can happen with WLAN in trains for example.

Log Music Listening Beta

This logs the currently listened music metadata and the current playback state.

  • Tested and working: Google Android Player, Amazon, Spotify
  • Not tested but should work: Google Android player, HTC Music, Apollo, Miui, Real, Sonyericsson, Rdio, Samsung Music Player, PowerAmp, Last.fm, Rhapsody, PlayerPro Music Player, Rocket Player, doubleTwist Music Player, Pandora, Winamp, 8tracks playlist radio, jetAudio HD Music Player, Spotify, Soundcloud
  • Tested and not working: Apple Music
Register social interaction or the interruptions from notification

Log Notifications Beta

This Logs all incoming notifications in an eventbased manner.

Label Description Type Default-Value
Filter Beta Only react to the given packages (Separated with ';') String
Measure social interaction

Log Phone Call Beta

This logs the phone activity in an anonymized way (Hashing of phone numbers).

By hashing the phone number, first an individual code will be generated. This code together with the phone number will be processed using the SHA1 hash algorithm. Because of that the hash number can not be assigned to the phone number later on. Furthermore it is not possible to compare the hashs of different participants. How a phone call can be displayed in the results is shown in this example:

442637,Call,type=Outgoing|number={"ONE_WAY_HASH":"1c3d3074811843e1e133a3cba16d506ecb7e8593"}|duration=121|time=13:44:53|date=2018-02-01

Log Physical Activity Beta

This logs the physical activity of the user (IN_VEHICLE: 0, ON_BICYCLE: 1, ON_FOOT: 2, STILL: 3, UNKNOWN: 4, TILTING: 5). This implementation is based on Google Play Services which detection algorithm could change even during a running study.

Activity confidence is a value from 0 to 100 indicating the likelihood that the user is performing this activity. The larger the value, the more consistent the data used to perform the classification is with the detected activity. This value will be <= 100. It means that larger values indicate that it's likely that the detected activity is correct, while a value of <= 50 indicates that there may be another activity that is just as or more likely. Multiple activities may have high confidence values. For example, the ON_FOOT may have a confidence of 100 while the RUNNING activity may have a confidence of 95. The sum of the confidences of all detected activities for a classification does not have to be <= 100 since some activities are not mutually exclusive (for example, you can be walking while in a bus) and some activities are hierarchical (ON_FOOT is a generalization of WALKING and RUNNING).

WARNING

Physical Activity cannot be measured accurately with a Smartphone. Smartphone accelerometers are not very accurate, differ between devices and the wearing position of the Smartphone varies. To accurately measure it please use a dedicated activity sensor like the movisens Move4.

Label Description Type Default-Value
Log interval Developer Minimal interval to log the physical activity in seconds. Activity may be logged more often, if requested by other apps. Integer 60
Measure social interaction

Log SMS Beta

This logs the SMS activity in an anonymized way (Hashing of phone numbers).

Log Steps Beta

This logs the steps.

WARNING

Steps cannot be measured accurately with a Smartphone. This is just an estimation based on 5 seconds of measurement of the Smartphone accelerometer in a minute. Smartphone accelerometers are not very accurate, differ between devices and the wearing position of the Smartphone varies. To accurately measure it please use a dedicated activity sensor like the movisens Move4.

Log Traffic Beta

This action logs the traffic usage.

Measure how much time the participants spends on his phone

Log Display On/Off Beta

This condition is true if the display is on.

Last Updated: 4/9/2019, 9:25:37 AM