Difference between revisions of "Experiment: Inclination"

From phyphox
Jump to navigation Jump to search
(Created page with "This is a placeholder for an experiment added in the upcoming version of phyphox.")
 
 
Line 1: Line 1:
This is a placeholder for an experiment added in the upcoming version of phyphox.
+
{{Infobox Experiment
 +
| Name = Inclination
 +
| Category = Tools
 +
| Sensors = Accelerometer
 +
}}
 +
 
 +
The experiment "Inclination" is a tool to measure the phone's inclination angles. It is designed to determine the angle of an inclined plane, so a phone resting on a table should show an inclination of zero. Additionally, a rotation is given, which gives the direction of the inclination (only makes sense if the inclination is not zero).
 +
 
 +
==Requirements==
 +
There are no requirements.
 +
 
 +
==Setup==
 +
There is no specific setup. You might want to check if the resting phone actually gives an inclination of zero. If your phone features a protruding camera it may be difficult to make sure it is lying flat.
 +
 
 +
==Analysis==
 +
 
 +
Phyphox uses the orientation of the earth's acceleration. The inclination is calculated as the atan2 of the z-component and the in-plane component as sqrt(x²+y²). Similarly, the rotation is the atan2 of y and x. To increase the precision, the accelerometer data is averaged over 500ms.
 +
 
 +
==Problems and resolutions==
 +
 
 +
* The rotation seems random. This is mathematically expected if the inclination is (close to) zero, because this should give the direction of the inclination on the xy-plane. If the inclination is zero, there is no component along x or y.
 +
 
 +
[[Category:Built-in experiments]]

Latest revision as of 20:57, 11 October 2016

Inclination
Experiment Inclination
Category Tools
Used sensors Accelerometer


The experiment "Inclination" is a tool to measure the phone's inclination angles. It is designed to determine the angle of an inclined plane, so a phone resting on a table should show an inclination of zero. Additionally, a rotation is given, which gives the direction of the inclination (only makes sense if the inclination is not zero).

Requirements

There are no requirements.

Setup

There is no specific setup. You might want to check if the resting phone actually gives an inclination of zero. If your phone features a protruding camera it may be difficult to make sure it is lying flat.

Analysis

Phyphox uses the orientation of the earth's acceleration. The inclination is calculated as the atan2 of the z-component and the in-plane component as sqrt(x²+y²). Similarly, the rotation is the atan2 of y and x. To increase the precision, the accelerometer data is averaged over 500ms.

Problems and resolutions

  • The rotation seems random. This is mathematically expected if the inclination is (close to) zero, because this should give the direction of the inclination on the xy-plane. If the inclination is zero, there is no component along x or y.