LPS331AP accessing filtering

christoph · ‎2013-12-21

Posted on December 21, 2013 at 21:50

Hi,

i'm a german student and i'm working on a private project. It's a UAV (UnmannedAirVehicle), which controls it's altitude by pressure. For this, i want to use a LPS331AP, but the raw-data output oscilates with a frequency of about 0.05 Hz. Normally, i would use a bandstop filter to reduce / minimize this noise, but if the UAV moves up or down, the frequency can be / will be often the same, so this doesn't fit.

In the application note ''Hardware and software guidlines'' it says on page 16:

''

For indoor navigation when sub meter detection is required, a special recursive filter could

be used. Tailoring the S/W filter for the sensor characteristic and the application requirement

is usually a good move. Sensor fusion is the most advanced filtering which uses all available

information and uses them to reduce the positioning noise.

''

But i can't find any more information about this ''recursive filter''. What sort if filter should this be? I'm allready using sensor fusion -> i double integrate a accelerometer to get the height out of it and use a complementary filter to combine this with the LPS331AP readings. But the noise frequency of the LPS331AP is too low to determine it.

I don't need to know the absolute pressure.

Thanks for reading & sorry for my bad english

#filter #lps331ap #noise

Thiago REIS · ‎2014-02-05

Posted on February 05, 2014 at 13:11

Hello,

Thank you for posting your question, I might be able to support you on this aspect of your UAV.

I am checking this information with STÂ´s application engineering team and I will let you know what is the outcome of that.

Please do not hesitate to contact me if there is any other item that you would like to receive assistance.

Thank you,

Thiago REIS

christoph · ‎2014-03-10

Posted on March 11, 2014 at 03:04

Hello,

first, thank you for your answer, but it's been a while since you've written it and i would like to know if there is allready something you can tell me.

I'm really waiting for your reply, because the project needs this sensor (or maybe another one, if this one doesn't fit).

Bye