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High Accuracy Indoor Location Tracking?

Posted by Cliff on from the where-did-it-go dept.

aletterman asks: "I am looking for technology that can allow my company to track the position of a fork lift as it moves around a warehouse. This would allow us to factor out one problem situation - where the lift was when the driver dropped off the product. Based on the width of our warehouse locations, we need a resolution of about +-1ft. Standard GPS can't get that accurate or work well indoors. The fork lifts already have a VT220 terminal running 802.11b, so adding another device would not be difficult. I am currently looking at a product that can triangulate via the RSSI of the 802.11b network, but I am concerned the changes in the product mix and density of the corrugated boxes will change the RSSI and introduce a mis-positioning of the locations. I would prefer that the device transmit a position either serially or via our 802.11b network. Our warehouses are fairly large (300,000+ sqft) and have a large of amount of corrugated boxes. Any suggestions are greatly appreciated!"

7 of 92 comments (clear)

  1. Grid by orkysoft · · Score: 5, Interesting

    Paint a grid on the floor, with squares of 1 sq. ft., possibly with magnetic paint, and install cameras or magnetic sensors to sense the lines passing underneath. Add a compass or rotational sensor to help determine the orientation. Add some maths, stir, and you might just have something that might work. (Or not...)

    --

    I suffer from attention surplus disorder.
  2. Re:dead reckoning by Glonoinha · · Score: 4, Funny

    Is that anything like one guy shouting out 'Marco' and the fork lift driver shouting 'Polo!' ?

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    Glonoinha the MebiByte Slayer
  3. Hockey Puck by Glonoinha · · Score: 4, Interesting

    Look into the technology used by the NHL on Fox for making the hockey puck more visible to the home viewers.

    Here is an oversimplified diagram, but enough to get you pointed in the right direction.

    --
    Glonoinha the MebiByte Slayer
  4. RFID by Yonder+Way · · Score: 4, Insightful

    Embed RFID tags in the floor. Put an RFID reader underneath the forklift. Have it report back over 802.11b with the RFID tag number(s) that it is closest to.

  5. Re:dead reckoning by 77Punker · · Score: 4, Informative

    Forklifts in warehouses can be difficult creatures. In the summer when I don't have school, I work at a place where sometimes I need to drive a forklift with flat, solid tires on a wet, greasy floor. It's a bit like ice skating at times, so determining the speed of the forklift could be quite difficult.

  6. Has been done before by freshmkr · · Score: 5, Informative

    Take heart---the problem you're contemplating has been fairly well studied.

    I remember a professor here at CMU saying that you could do localization for forklifts by pointing a camera at the floor. Most warehouse floors have enough scratches and marks on them that as you wander around, you can get a pretty good idea of where you are by comparing them to a map (using techniques like Monte Carlo localization---google it!). Combined with encoders on the forklift wheels, you may be able to get the resolution you need.

    Here is a paper describing technology like this. In the results they say they get accuracy down to a millimeter.

    So, those talking about painting a grid on the floor have the right idea---but perhaps you don't even have to do that!

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    MAN SHOOTS ROVER!
  7. Differential GPS by Anonymous Coward · · Score: 4, Informative

    centimeter accuracy using indoor differential gps

    http://www.gpsworld.com/gpsworld/article/articleDe tail.jsp?id=3086