Telling Position Of Cart

Can you share some ideas on the different ways of telling the position of a push cart as it travels through a wharehouse. The cart would be pushed by the operator and location of the cart is important so a display can indicate where the operator needs to go next (bin location). Technology under review now is RFID and sensor arrays. Has anyone else had to do this or have any ideas to share. Thanks!

I question why you care where the CART is? If you're picking orders, you can tell where the cart is by knowing which bin the operator last picked a part from (for instance, when they scan a bar code).

Or, are you trying to direct the operator 'turn by turn' to the next bin?...

Have you considered GPS?...

beerchug

-Eric

You should turn it around this way:

The position of where the cart has to go, should be so logical and selfevident, by using a position code so that he doesnt need directions but will find the way himself.
Example: AL-01-03: Aisle "A" left side - Column 01 - Shelf 03.

You then have to tell the cart operator where to go (not how to). This you can do by a number of ways:
1. An offline terminal with a list of the positions where he has to go.
2. An online terminal which is updated every time he has to go to a new place.
3. Stickers on each item on the cart with the position code.

You could combine a terminal with a code reader. When dropping or picking an item, he has to read a code off the item and off the shelf, thereby doublechecking that it is the right position.

Hi All
Frankly Speaking i am not very much aware about the system you are talking about .As i understand this Cart may pick something from a certain position such as book in a bookstore or a product from stores...etc
I am thinking about using Linear Encoders for example but i can't recommend any thing until i have a clear view.
BR

Put GPS and you will have the location.Joke

I try to make combination between Eric idea to mine.
you need to use wireless unit to communicat with him.and screen.
You know which is the first point he need to go,
when he rich the first point he need to Acknowledge that he in certine point, then you transmit the next point.Sound logical?
You can know where the cart or between what points he is.

Here sia link to the Siemens Mobic. It is standard with a wireless ethernet card built in. It supports a GPS card or barcode reader in an external PCMCIA card. http://www4.ad.siemens.de/WW/llisap...6&lang=en&content=skm/search.asp?&Query=mobic

Why on Earth would someone want to spend time and money designing some fancy means to show the way for a human?! That person, the cart-pusher, however dumb and uneducated it may be, still is immensely more intelligent than any machine.

It is an overkill par exellence. In my opinion, a project like that would not go past the basic "sanity check". Sorry.

We have a system that is along the same lines as you are thinking... with one major difference: Our system is automated by a track guided vehicle where your system is dependant on a human to guide and direct the vehicle.

On the TGV (track guided vehicle) system an operator enters into a touch screen the location the vehicle is to go for product to be delivered. The system will automatically pick up empty containers. A PLC directs the vehicle to the proper station and priority of tasks with prox detectors telling the system where the vehicle is. The prox detectors are arranged in a bar code type of pattern so each station has a unique indentifier. In this manner an array of 8 sensors can give you 256 unique locations.

In your system the type of sensors you use will depend on the limiting factors and error potentials. Prox detectors would require the cart to be within a few millimeters of each station consistently. You could try PhotoElectric sensors with reflectors on the cart. The RFID seems to be the latest trend for this and may very well be the most error resistant for your system.

Thanks to everyone who posted. However crazy to some, the customer has the desire to not only tell the operator you are here, but here is the recommended route to the next stop. Not only do they want to reference the best route, but also confirm that the operator has gone that way too. Anyway the customer has signed off on doing an RFID system.