Reading bar code under moving Model (HO) car

[fieryturbo]

I seriously have no idea why it seems like this forum is totally disconnected from ANY model railroading technology that comes from Europe.

Already exists: Barjut bar code reading for model railroading:

http://wiki.rocrail.net/doku.php?id=barjut-en

[Eric White]

We had an article in Model Railroader:

RFID for model railroad operations

Using radio-frequency identification and a computer to track rolling stock opens new possibilities for operation

by Chris Drome  Seth Neumann 

from Model Railroader December 2014 

 

Seemed to work pretty well.

Eric

[DSchmitt]

Pete Laabs

Dave,

As it's been almost 9 years. What option or system did you end up using? Barcode, RFID or something else?

I am in the design / construction phase and am hoping to incorporate all the latest technology to totally automate my layout when I just want them to run. DCC/LCC/JMRI...

Thank you,

Pete 

 

Would be interesting to know, but the OP hasn't posted on this Forum since 2010.

Does any member have a tracking system on their model railroad or know someone who does?

[Pete Laabs]

Dave,

As it's been almost 9 years. What option or system did you end up using? Barcode, RFID or something else?

I am in the design / construction phase and am hoping to incorporate all the latest technology to totally automate my layout when I just want them to run. DCC/LCC/JMRI...

Thank you,

Pete 

[dehusman]

For a display layout, you really don't need every car to have a code, just the engines minimally and maybe just the rear car.  Even in N scale , a bar  code could be 3/8 to 1/2 in wide and maybe an inch long.  You could also put multiple copies of the codes on the first 3 engines and last 3 cars so the chances of getting a correct read are improved.

The head end read would indicat a block or OS section occupied and the rear car reading could indicate a block or OS section unoccupied.  For that matter you could put a "head end" barcode on all engines and a "rear end" bar code on the last 3 cars, the same code on all engines and the same code on all rear cars.  Since OP is just tracking occupancy on a display layout, all he may really need to know is there is a train there, not necessarily which train and almost certainly not which cars. 

[betamax]

No, they are designed to work at much higher frequencies, and require the detector to stimulate them first, at much higher power levels than they emit.

[caldreamer]

Thinking about it from a programmers point of view which I did for many years, if I put an RFID in only the engines/.  If the magnetic field and electronics signals from the decoder did not interfere with the RFID  signal, the program that I am writing will know the cars assigned to a train.  By knowing when the locomotives on a train passes an RFID detector you would know where a train is locted on the layout.

My question is will the RDFID signal interfere with the radio DCC signals and what about the magnetic field from the motor? 

[rrinker]

 Uhlenbrock has their LiSSy system, but that's not a barcode, a small ir transmitter is on each loco ro car and transmits an address to the reader as it passes over. Sounbds like it is reliable, though the translated to English version of the instructions are somewhat lacking. If you can read German, the original instructions ans specifications are on the Uhlenbrock web site.

 However, putting an active device in every car is not going to be cheap or easy. Some sort of wheel pickups will be required for all freight cars, and hiding all that on a flat car might be difficult. The transmitter unit is VERY tiny and easily hidden.

                --Randy

[caldreamer]

I know that when they scan our items at the grocery store , the clerk has to scan some items more than once because the reader did nt pick up the bar code.  I am wondering how reliable they woudl be reading a moving car.  Are there RFID atrips that are small enough to go inside or under an N scae car would they be read reliably/

     Ira

  

[betamax]

CTI Electronics TBrain has RFID possibilities, they also offer the hardware.

Links to a reader that some have been using with success.

[BATMAN]

Would it be possible to rig up some shielding to block out signals except from one direction. Just a thought.

[rrinker]

 Bunch of people have been workign with RFID, the problem is that even the most limited range devices are a bit much for model railroads - say a yard with 4 parallel tracks, the unit on track 2 also reads cars on track 1 and track 3. In a situation where there are no nearby tracks, it should work well. Say, a staging yard with a single track linking it to the main, or maybe 2 tracks, one for each direction. An RFID reader on each connector track would be able to track which cars are heading on and off the layout in each direction. I think they have that working pretty reliably now - it's just when you get more than one track in a small space, the reader picks up everything within range.

 

                 --Randy

 

 

[BATMAN]

My wife is a Veterinarian, she always has a good supply of these chips on hand. Whenever she orders a bunch they always send her a free scanner with them. I suppose if you ordered a hundred or more you could get them for about $5.00 a pop.

[JDberlin]

The English model railroaders have been using RFID detection for some time.  They already have the modules and technology for an engine's special needs and for the the simple rolling stock. Most are stick-on applications.  Why not just make the effort to contact them?

[betamax]

There is a yahoo group about RFID applications for model railroading, pretty quiet as there is not a lot happening. But people are working on using this technology.

You can get tags that are about the size of a grain of rice, which can be mounted on a truck frame and read by a sensor under the track.  The data can be sent to an application that can use it.  You could even use it to keep track of your locomotives and link them to a database with all the important details...

[Redore]

RFID is what the real railroads use too.  They have a tag about 2 inches by 6 inches rivited or welded to both sides of the car.

 

nfmisso

Dave;

RFID is the way to go, the tags do NOT have a power source, they are powered by the radio frequency query signal.  This is the same technology put in cats and dogs to identify them, aka "chips".  Do a Google search on RFID.  RFID is used in pallets on automate assembly lines identify the particular model on the pallet, record test data and other purposes.

[steemtrayn]

Six years, eh? I wonder if they figured it out by now.

[ericboone]

I believe you can get RFID labels that are about as thick and about the same size as a small barcode label.  In volume, they are very cheap.  Because as previously stated, RFID or bar code scanning only tells you when a car is at a particular scanner, it has limitations.

I plan on wiring my layout to use the NMRA bi-directional communications protocol or Digitrax transponding.  (I haven't decided which yet.  The bi-directional is the standard, but is very new and immature while transponding has been around for a while now.)  Then, when the chips get smaller (axle mounted maybe) and cheaper, I hope to equip every car with one so I know were every car on the layout is located.  Then, I could scan the entire layout between operating sessions to get an updated location for every car to somehow dump into a Ship It or Rail Op type program.

[reklein]

How about no scanner system at all. This won't solve your inventory problem but might solve the operation problem. My suggestion is to use a Hall effect system. A magnet on the loco and the last car in the train is detected by a sensor under the track. If the last car is not detected wire the train to shut off automatically. Should work something like the automatic grade crossing detectors on the prototype. You could still have a barcode for inventory.

[Beowulf]

Nfmisso reminded us that RFID is small enough to inplant in pets.  I had only thought of the larger E-Z Pass units that stick to our car windshields and the even larger ones on prototype railroad cars.  These tiny RFID units would be the way to go as they wouldn't require a flat area on the car underside.  RFID would also allow great flexibility in locating the reader.

[CSX Robert]

You will need a white light to illuminate the bottom of the cars as they go over the scanner. Many people are of the mistaken idea that the scanner reads the black bars. Uh-uh! The scanner reads the white area between the black lines by the amount of light reflected back to the scanner. White reflects light, black doesn't.

I thought the hand scanners we used would work in the dark, but I did not say anything about this in my previous post becasue I wanted to test it and make sure. When I got in to work today, I tested them and they will work in the dark.

Here is one of the suppliers we have delt with:
http://www.posguys.com/

[dehusman]

For model railroad purposes you don't need a programable chip, just a regular "dumb" chip with just an inventory number will do.  all the car data can be stored in a program external to the chip (like the program you use to actually do something with the info.)

The problem with scanners is that at the lowest level all they give you is a timestamp that a car was at a certain place at a certain time.  To make decisions you actually need another piece of information, what direction was the car going.  By knowing the direction you can automate some decision information.  The problem on a model railroad is is there enough time between when the scanner passes a reader and when the train has to do something to read the cars, make the manipulations and then create some form of output that the operator can use?

Dave H.

[dehusman]

They some what do. They have these tower on the side of the right of way. These work almost work just like a barcode scanner.Tthey recieve the info from a plate on the side of a car.

Actually no.  They stopped doing that back in the 1970's.

The technology they use now is RFID chips attached to the car or container that are read by a transponder.  Doesn't need to "see" the car at all.

Dave H.

[twcenterprises]

I have a contact (not really a friend, sort of an acquaintance) who works for a company that is doing a new sort of RFID technology.  He said (last I talked to him) his company was beta testing and field testing some new RFID modules.  To make a long, technical explanation short, these tags were supposed to be in the "cents per piece" price rance, and the readers in the "under $100" range, and reader/programmers, no more than $200 or so.  He said the "tags" could be either reprogrammable, or programmed once, then read only afterwards.  The read only one would be good for (his example) in a bridge, you take a concrete sample, do your lab tests on it, and embed the tag in the concrete, then program it (while the concrete cures) with date, time, temp., lab results, etc., etc.  The reprogrammable ones were ideal for nearly anything, automotive suppliers, retail, auto parts, whatever.  I'll check with him (if your interested) to see how small the ID tags can be had.  If they are small enough, it might be worth looking in to.

Brad 

[BATMAN]

Just a suggestion. You might get out dated hand held scanners from courier companies or the post office. They seem to upgrade often. Another thing I came accross in our latest upgrade is the scanner takes a PHOTO of the barcode and transmits that to the computer. How it all works and why the change I don,t know, but the red light that you point at the barcode is now a dot. This new technology might work better for you, especially if you are using acomputer to run that huge layout.

[cheese4432]

Dave;

RFID is the way to go, the tags do NOT have a power source, they are powered by the radio frequency query signal.  This is the same technology put in cats and dogs to identify them, aka "chips".  Do a Google search on RFID.  RFID is used in pallets on automate assembly lines identify the particular model on the pallet, record test data and other purposes.

Well in that case rfid trumps barcode scanner. But how big are these? are they like a surface mount led?or bigger?

[tohowalk]

Sounds (and looks) like quite the project. There are some photos on the museum website: http://www.railroadmuseum.net/

 

Tom

[eeyore9900]

I definitely agree on the point of wand type scanners not being reliable. Working in

a public library myself, I've used these puppies for quite awhile. The wand type were

absolutely horrible, & like was said above, even with direct contact with the bar code.

We finally got rid of them & got some hand helds which work much better too. Might be

worth some "in motion" experiments when I work the audio visual desk tomorrow!

 It's a good idea though, & definitely worth some thought.

[CSX Robert]

I would suggest that you forget about the wand type of scanner, the way they operate, I doubt that you could get any distance out of them. Besides that, they do not operate very reliably even when in direct contact with the barcode.

I've delt with the handheld scanners quite a bit at work. They work very reliably and some of them can be set to scan continuously. I can get some prices if you want me to. How do you intend to interface the scanners with the PC? We can get them with an RS-232 (serial) interface or USB. There are advantages to both and what would work best for you might depend on your software and operating system. We can also get small modules that would be a lot easier to mount, but I believe they are quite a bit more expensive.

I will give you this piece of advice. You say most are way more complicated(expensive) than is necessary. I don't know what price range you are looking for, but you don't want to go to cheap for what you are doing. It won't be very useful if the scanner does not scan the car virtually every time.