To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.roboticsOpen lugnet.robotics in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / 27976
27975  |  27977
Subject: 
Re: Kalman Filter on the NXT
Newsgroups: 
lugnet.robotics
Date: 
Fri, 28 Dec 2012 18:12:36 GMT
Viewed: 
29286 times
  
In lugnet.robotics, Claude Baumann wrote:
> The Kalman Filter may be perceived as a discouraging, almost occult calculation
> method. Many do apply the filter just by following some "cooking recipes", and
> they don't care much about the internals. However, if the filter is well studied
> and adapted to the current problem, then --tada-- things may appear very easy...
> and its use on the NXT is no secret anymore.
> 
> If you want to learn more about the Kalman Filter, then have a look at its
> implementation into a simple application on www.convict.lu/blog/?p=230. A
> vehicle drives don't the inclined plane, and wants to exactly know its speed and
> position. It is equipped with an accelerometer, a tachometer -made of a LEGO
> legacy motor, used as a DC-generator- and a legacy rotation sensor. Every sensor
> has its own trouble of accuracy and precission:
> 
> - the accelerometer is caracterized by an important drift, making computation of
> the speed, and position (by integration) very error-prone
> - the tachometer has a significant ripple due to the motor coils.
> - the rotation sensor has a lack of precision, because of its bad resolution
> (1/16th)
> 
> Now, the Kalman Filter overcomes all of these issues, by considering the system
> model, which allows to predict, how the system will behave. Then the
> measurements are used to correct the predictions. The predictions are based on
> Galilei's equation of the motion. However, the system will not exactly obey this
> equation, because the world introduces errors: the plane is not totally even,
> for instance. The Kalman Filter merges everything, the sensor readings and the
> model estimations into the best possible estimation of the system at any time.

All over my head.

But, if and when I actually get my GPS robot working, I'm going to look this up
again.

Dave K



Message has 1 Reply:
  RE: Kalman Filter on the NXT
 
I have a memory from attempting to use the Kalman filter, starting with a model, and working through the math, that it made some assumptions, which importantly included an originally good sensor signal subsequently clouded by noise. Kalman can (...) (14 years ago, 28-Dec-12, to lugnet.robotics)

Message is in Reply To:
  Kalman Filter on the NXT
 
The Kalman Filter may be perceived as a discouraging, almost occult calculation method. Many do apply the filter just by following some "cooking recipes", and they don't care much about the internals. However, if the filter is well studied and (...) (14 years ago, 28-Dec-12, to lugnet.robotics)

4 Messages in This Thread:

Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR