I am pretty new to Android and decided to play around with the sensors. I always find accelerometers fun to play with, and like to visualize the sensor reading through a real time plot. In the java-script for the android app below, the acceleration in the x axis is read and streamed through a TCP socket to the PC over wlan. A simple python server script reads the data from a socket and writes it to a perl script, logging the data in GnuPlot, and thus setting my personal record for mixing different languages.

The simple python server script below opens a TCP socket and receives the readings from the Android app over WLAN. Note that the python script reads the last entry in the receive buffer, which then makes up a LIFO que, and no timestamp is added to the reading. For a signal analysis one would add a time stamp and a FIFO que should be used instead. For debugging and pure fun, the method I used is still pretty sufficient. ` The plotting is excecuted with piping the output from the python script to the perl script in the linux terminal:

$ ./server.py | ./driveGnuPlot.pl 1 500 "Accelerometer Reading"

Python server :

And lastly the python script pipes data to a Perl script written by Thanassis Tsiodras.



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Published

30 April 2012