Hello everyone on stackoverflow.
SHORT VERSION :)
I need to use (x, y, z) acceleration values related only to iPhone movement. To be clear, think about an environment like a car. The iPhone accelerometer is very sensitive. If you register acceleration values with a frequency of 100 Hz, there are so many values associated with noise, vehicle vibrations, and other acceleration vectors that are not directed like iPhone movement (for example, vibrations of the shutters cause acceleration vectors directed along the z axis).
In other words, I need to filter out the detection of accelerations in such a way as to highlight the accelerations whose direction is the same (within a certain offset) the direction of motion.
DEEP CONSIDERATIONS: '(
Obviously, I could fix the position of the iphone so that its y axis overlaps the direction of movement (in the previous car environment, this means fixing the iphone y axis parallel to the front direction). The problem is that I need to resolve the relative moments of the iphone. I can not fix the position of the iphone.
First of all, I analyzed the values created by noise and vibrations, and I realized that their value is often much higher than ordinary car accelerations. Filtering magnitude is a good idea to alleviate the problem, but it is not a solution: on the one hand, many unwanted noise accelerations are not filtered because their value falls into the range, on the other hand, many desired motion accelerations are filtered because they are outside the range.
iPhone 3GS . , , : . , iPhone .
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