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accellog

Return logged acceleration data from mobile device sensor

Description

example

Add-On Required

To use this function for accessing mobile device sensors remotely from MATLAB® installed on a desktop or laptop computer, you must also install either MATLAB Support Package for Apple iOS Sensors or MATLAB Support Package for Android® Sensors. For more information, see Get and Manage Add-Ons.

[log, timestamp] = accellog(m) returns the acceleration log, where m is the name of the mobiledev object that acquires the sensor data. log is an N-by-3 matrix containing acceleration data points, and timestamp is an N-by-1 vector of timestamps, where N is the number of samples acquired in the capture duration.

Examples

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This example assumes that you have already installed and set up MATLAB Mobile™ on your mobile device. If you have not, see Install MATLAB Mobile on Your Device.

If you want to read the data in a different session of MATLAB, start MATLAB Online™ or MATLAB on your local computer.

Start MATLAB Mobile on your device.

On the Sensors screen, tap the Acceleration sensor.

Place the mobile device where you want to get the sensor data.

In your MATLAB session, create a mobiledev object, m.

m = mobiledev

Begin logging data by enabling the Logging property.

m.Logging = 1

This action starts the transmission of data from all selected sensors. You can also start transmission by tapping the Start button in MATLAB Mobile.

Get the logged acceleration data.

[a,t] = accellog(m)

This returns the acceleration log, where a contains the three data points for the acceleration reading in X, Y, and Z coordinates, in m/s^2 (meters per second squared).

See Device Orientation for a diagram showing the X, Y, and Z axes relative to the device.

Output Arguments

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Name of variable for acceleration log data, returned as an N-by-3 matrix of data points from the Acceleration sensor on the mobile device. The three data points are the acceleration reading in X, Y, and Z coordinates, in m/s^2 (meters per second squared).

Acceleration is defined in relation to the X, Y and Z axes. If you set the device down face-up on a table, the positive X-axis extends out of the right side of the device, positive Y-axis extends out of the top side, and the positive Z-axis extends out of the front face of the device. This is independent of the orientation of the device.

Name of variable for timestamp, returned as an N-by-1 vector of timestamps from the Acceleration sensor on the mobile device. Time is in seconds, relative to the InitialTimestamp property.

Version History

Introduced in R2015a