Monte-Carlo Localization

Question

I'm implementing Monte-Carlo localization for my robot that is given a map of the enviroment and its starting location and orientation. Mine approach is as follows:

Uniformly create 500 particles around the given position
Then at each step:
- motion update all the particles with odometry (my current approach is newX=oldX+ odometryX(1+standardGaussianRandom), etc.)
- assign weight to each particle using sonar data (formula is for each sensor probability*=gaussianPDF(realReading) where gaussian has the mean predictedReading)
- return the particle with biggest probability as the location at this step
- then 9/10 of new particles are resampled from the old ones according to weights and 1/10 is uniformly sampled around the predicted position

Now, I wrote a simulator for the robot's enviroment and here is how this localization behaves: http://www.youtube.com/watch?v=q7q3cqktwZI

I'm very afraid that for a longer period of time the robot may get lost. If add particles to a wider area, the robot gets lost even easier.

I expect a better performance. Any advice?

The performance shown in the video is good, considering a single sonar sensor. Do you have an example video of the robot being lost? — Demetris, Jan 21 '14 at 08:35
There are actually 5 sonars, would still say it's good? I don't have a video of the robot getting lost, but I'll try it today on a real robot. — Andrei Ivanov, Jan 21 '14 at 15:33
It's not clear to me what your concern is. The PF you implemented seems to work fine. Maybe you can be more detailed on what you think is the problem. — Demetris, Jan 21 '14 at 19:47
Please don't ask the same question on multiple stack exchange sites. If you accidentally ask on the wrong site, it can be migrated to the correct one. — Mark Booth, Jan 22 '14 at 02:13
Welcome to Robotics Andrei Ivanov. As it stands it isn't clear what your actual question is here. We prefer practical, answerable questions based on actual problems that you face. Take a look at [ask] and [about] for more information on how stack exchange works, and think about how you can edit your question to make it more answerable. — Mark Booth, Jan 22 '14 at 02:16
I like Johnny Mudcrab's answer linked below, but I would argue Robotics is the best Stack Exchange site for it to be located. Mark Booth notes above that questions can be migrated. Is it possible to migrate answers? — AndrewCr, Jun 29 '14 at 21:19

score 2 · Answer 1 · edited May 23 '17 at 12:37

2

I just answered the question on StackOverflow, where it already been asked. Here is the link:

https://stackoverflow.com/questions/21249131/monte-carlo-localization-for-mobile-robot

edited May 23 '17 at 12:37

Community

1

answered Jan 28 '14 at 10:20

Johnny Mudcrab

193
6

read your answer you are right :) – Neo Feb 04 '14 at 06:46

Monte-Carlo Localization

1 Answers1