RandomSequence

  • Subscribe to our RSS feed.
  • Twitter
  • StumbleUpon
  • Reddit
  • Facebook
  • Digg
Showing posts with label roomba. Show all posts
Showing posts with label roomba. Show all posts

Monday, November 19, 2012

Roomba navigation algorithm

Posted on 12:52 PM by Unknown
I have been a long time user of the Roomba vacuum robot, starting from version 1 till now. It has made a big difference to my life, and I enthusiastically recommend it to all my friends.

One thing that stands Roomba apart from other vacuum robot is its navigation algorithm. There is no high-level mapping involved. Instead it uses localized decision making, much like how insects forage for food:

Our robot computes its algorithm 67 times every second, constantly stitching together information about its environment and recomputing its path. When it starts you’ll notice a spiral pattern, it’ll spiral out over a larger and larger area until it hits an object. When it finds an object, it will follow along the edge of that object for a period of time, and then it will start cris-crossing, trying to figure out the largest distance it can go without hitting another object, and that’s helping it figure out how large the space is, but if it goes for too long a period of time without hitting a wall, it’s going to start spiraling again, because it figures it’s in a wide open space, and it’s constantly calculating and figuring that out. It’s similar with the dirt sensors underneath, when one of those sensors gets tripped it changes its behaviors to cover that area. It will then go off in search of another dirty area in a straight path. The way that these different patterns pile on to each other as they go, we know that that is the most effective way to cover a room. The patterns that we chose and how the algorithm was originally developed was based off of behavior-based algorithms born out of MIT studying animals and how they go about searching areas for food. When you look at how ants and bees go out and they search areas, these kinds of coverage and figuring all of that out comes from that research. It’s not exact, obviously, I’m not saying we’re honeybees, but it’s that understanding of how to search out an area in nature that is the basis behind how our adaptive technology is developed.
The algorithm is actually quite effective and robust in the real world. For a short while, I used to house two cats in a room, and you can imagine how dusty that was. Roomba never failed to clean up the room for me after I left it to its devices. It was squeaky clean after each session, and all I had to do after that was to give the wooden floor a quick mop.

Don't take my word for it. Check out this video providing a time-lapsed coverage test of various vacuum robots, including The Roomba 5 series.


However, I never fail to notice, both online and off, how Roomba's navigation algorithm invokes all kinds of negative feeling in users. Comments typically are of the types:

... It is just going in random directions
... Personally I will not vacuum like that
... Why does it go over the same area twice?
... It is not very efficient, it takes too long 

I have seen people just standing there and supervising/criticizing their robot's every move! This is crazy! Do you stand there and supervise your washing machine? I mean, you just dump your clothes in, set a wash cycle, and come back in 45 mins or whatever. What's so difficult about that? Instead you have people just hanging around and second guessing every move the robot makes. Absurd!

I can understand maybe a robot vacuum cleaner is something new to a lot of people, it hasn't become quite as mundane as a washing machine. Or maybe a localized or bottom up algorithm is just harder to understand/accept compared to a top-down algorithm. Rodney Brooks, the co-founder of iRobot, the company that makes Roomba, is a pioneer in the field of bottom-up robotics. He famously created robotic insects that do not have a central "brain", but instead make localized decisions based on the feedback from various sensors (much like the Roomba). In the physical world, that approach turns out to be extremely robust and resilient.

AFAIK iRobot has never organized any campaign to dispel such negativity. I guess maybe it is just too difficult and technical to make people understand that a bottom-up approach is superior to a top-down (mapping) approach. I hope I can make a small difference by blogging about this here. Roomba's navigation algorithm in the real world is robust. You can move furniture around while the robot is running and not have to worry that it won't come back again. You can let it bump into your foot if you are doing stuff in the same room while it is running, but you can be assured that will not have a large impact on what it is doing.

You don't want a robot to vacuum like you do. Otherwise, cars will have legs, and washing machines will have arms. Just clear the room, set the robot down, let it run, grab a cuppa and come back an hour later. The room will be clean. Trust me.
Read More
Posted in hardware, roomba | No comments
Older Posts Home
Subscribe to: Posts (Atom)

Popular Posts

  • 110GB+ worth of photos/videos on a microSD memory card #2
    In my previous post, I talked about wanting to write a script to see how far I can squeeze 110GB worth of media (photos and videos). I wrote...
  • Looking for the perfect car MP3 player/FM transmitter
    I have bought quite a number of car MP3 player/FM transmitters from DealExtreme and other similar websites. A car MP3 player/FM transmitter...
  • Children - The ultimate test in anger management
    Having just spent two full holiday weeks with my kids, it occurred to me this morning that raising young children is the ultimate test in an...
  • Coding the Liturgical Calendar
    For a long time, I've wanted to integrate the Roman Breviary into a couple of projects (nothing public) but have never been able to find...
  • Ubuntu: WebDAV + DAVfs2 + FUSE == Thunar Goodness
    One of the corner-stones of any *nix utility is that it should do a simple job and do it well. Every piece of software that I can think of ...
  • Fast Diet - Hunger Pangs
    When I am doing the Fast Diet , I frequently experience long periods of calm after a brief period of hunger pangs. It is as if the body has ...
  • ...and this is why I'm Catholic
    When I was looking for answers from the Methodist church about all the things I was wondering about as a teenager, I was dismayed to find t...
  • Fast Diet - Incredible Body Hack
    In terms of body hacks, the Fast Diet probably ranks all the way at the top for me. I first read about it in the papers and found the techn...
  • Jamming Flagpoles
    Today I read a report about Iran's alleged "flagpole jamming network".  Reading all of this, it became plainly obvious that, ...
  • Whacked-out Weather
    So, its no mystery to anyone that the weather has been WEIRD this year, but here's just how weird it has been... this evening, on my way...

Categories

  • a2dp
  • administrata
  • android
  • antivirus
  • avi
  • bluetooth
  • chrome
  • coding
  • culture
  • dos
  • eee
  • faith
  • family
  • fastdiet
  • firefox
  • gadgets
  • geeekry
  • geekery
  • hardware
  • homeschooling
  • howto
  • java
  • laptop
  • life and the universe
  • linguistics
  • link2sd
  • linux
  • migration
  • mp4
  • pdf
  • politics
  • printer
  • roomba
  • security
  • soapbox
  • software
  • transcode
  • travel
  • ubuntu
  • video
  • virtualization
  • webapps
  • windows

Blog Archive

  • ▼  2013 (11)
    • ▼  August (3)
      • 110GB+ worth of photos/videos on a microSD memory ...
      • 110GB+ worth of photos/videos on a microSD memory ...
      • Coding the Liturgical Calendar
    • ►  July (6)
    • ►  June (2)
  • ►  2012 (25)
    • ►  December (2)
    • ►  November (4)
    • ►  October (4)
    • ►  September (1)
    • ►  June (11)
    • ►  May (3)
  • ►  2011 (11)
    • ►  December (1)
    • ►  September (2)
    • ►  August (1)
    • ►  July (3)
    • ►  April (1)
    • ►  March (1)
    • ►  February (1)
    • ►  January (1)
  • ►  2010 (10)
    • ►  December (2)
    • ►  October (1)
    • ►  September (1)
    • ►  August (2)
    • ►  July (1)
    • ►  May (1)
    • ►  March (1)
    • ►  February (1)
  • ►  2009 (29)
    • ►  December (2)
    • ►  November (2)
    • ►  September (1)
    • ►  August (3)
    • ►  July (2)
    • ►  June (5)
    • ►  May (2)
    • ►  April (2)
    • ►  March (6)
    • ►  February (3)
    • ►  January (1)
  • ►  2008 (57)
    • ►  November (2)
    • ►  October (4)
    • ►  September (1)
    • ►  July (8)
    • ►  June (3)
    • ►  May (8)
    • ►  April (12)
    • ►  March (6)
    • ►  February (8)
    • ►  January (5)
Powered by Blogger.

About Me

Unknown
View my complete profile