Automated Data Collection (ADC), also known as Automated Data Capture
(ADC), Automated Identification (AutoID), Automated Identification and
Data Capture (AIDC), and by many as just "Barcoding" consists of many
technologies including some that have nothing to do with bar codes.
Voice systems, RFID, OCR, pick-to-light, laser scanners, CCD scanners,
hand-held batch and RF terminals, vehicle-mounted computers,
and wearable computers are all part of the ADC picture.
The fear of six-figure project costs often prevent many small to
mid-sized manufacturers and distributors from taking advantage of
Automated Data Collection (ADC) technologies. The key to implementing
cost-effective ADC systems is knowing what technologies are available
and the amount of integration required to implement them. Applying this
knowledge to the processes in your operation will help you in developing
the scope of your project. Limiting your project to or prioritizing by
those applications that have a high benefit/cost ratio will allow you to
apply these operational improvement technologies within a reasonable
budget. For example, adding a keyboard-wedge bar-code scanner to
an existing PC or terminal in a production or warehouse area is a very
low cost method for applying ADC to existing shop-floor reporting and
shipping applications. This type of hardware is inexpensive and the only
real programming required is that needed to add a bar code to the form
(work order, pick slip, etc.)
Bar codes
There
are two major categories of bar codes, one dimensional (1D), and two
dimensional (2D). 1D barcodes are the ones we are most familiar
with and consist of many different symbologies including UPC, Code 128,
Code 39, Interleaved 2 of 5, just to name a few (there may also be
variations within a specific symbology). The symbology you use may be
dictated by supply chain partners through a standardized compliance
label program or, if only used internally, can be chosen based upon
specific application (tip: if looking for a flexible symbology to
use internally on documents, labels, license
plates, etc. you will find
Code 128 a good choice).
2D bar code symbologies such as UPS's
MaxiCode (shown right), are capable of storing more data then their 1D
counterparts and require special scanners to read them. Although I would
expect to see continued growth in the use of 2D bar codes, most
warehouse and shop floor applications will continue to use 1D
symbologies simply because the technology is less expensive and you
generally only need enough data in the bar code to access the associated
records in your inventory system database. The 1D codes are very capable
of accomplishing this. If you're interested in more detailed information
and specs on bar codes I recommend getting a copy of
The Bar Code Book by Roger C. Palmer.Bar-code scanners
Laser or CCD.
There are primarily two technologies used to read
bar codes. Laser scanners use a laser beam that moves back and forth
across the bar code reading the light and dark spaces. Laser
scanners have been in use for decades and are capable of scanning bar
codes at significant distances. CCD (charged coupled device)
scanners act like a small digital camera and take a digital image of the
bar code which is then decoded. CCD scanners offer a lower cost
but are limited to a shorter scan distance (usually within a few inches,
however, the technology is advancing quickly and devices with longer
scan distances are becoming available). Because of the scan
distance limitations, users in a warehouse environment will likely find
laser scanners to be their best choice however for applications were bar
codes are read from documents — such as in a shop-floor
production-reporting application — CCD scanners should work fine.
Autodiscrimination.
Autodiscrimination describes the
functionality of a bar code reader to recognize the bar code symbology
being scanned thus allowing a reader to read several different
symbologies consecutively. Most scanners come with this
functionality and also allow you to program them to read only certain
symbologies (this prevents someone from scanning the wrong bar code when
multiple bar codes are present).
Keyboard-wedge scanners.
Keyboard-wedge scanners connect
between a computer keyboard and the computer and send ASCII data to the
computer as if the scanner were a keyboard. More simply put, the
computer doesn't know that a scanner is attached and treats the data as
though it were key strokes from the user. The advantage of this is
that there is no need for special software or programming on the
computer. In its simplest application you hook the scanner up, make sure
the curser is in the correct field, scan a bar code containing the data
you need such as a work order number, an item number, or a location, and
the data will immediately appear in the field on the screen.
Although this type of application can prove to be very useful and
essentially works right "out of the box", you will find that by taking
advantage of the programmable features of some devices you can take this
functionality much further. This is where it gets a little
confusing as the programming and functionality is a little different
based upon the hardware and software you purchase. Some
keyboard-wedge scanners have built in programming functionality, while
others are programmed on a separate wedge decoder, and there is also PC
software that can perform tasks related to the data input from a
scanner. The good news is that you don't need to be a programmer
to use this functionality. If you have ever worked with macros
you'll easily understand this type of programming. What most of
these programs allow you to do is to parse data from a bar code
(allowing you to put several pieces of data in the same bar code such as
item number and quantity, or customer number and shipping method) and
also add keystrokes not included in the bar code such as tabs to move
between fields, default data, function keys or enter keystrokes to
complete transactions.
Keyboard wedge scanners offer a low cost entry into the world of
automated data collection and can provide increases in accuracy and
productivity in many stationary data entry applications. There are also
wireless versions of keyboard wedge scanners available.
Fixed Position Scanners.
Fixed position scanners are used where
a bar code is moved in front of the scanner as opposed to the scanner
being moved to the bar code. Applications include grocery check
out counters and automated conveyor systems. Many fixed position
scanners are omni-directional which means that the bar code does not
have to be oriented any specific way to be read.
Go to Accuracybook.com's
Bar Code
Scanner Links.
Portable computers
Portable computers come in a vast variety of designs with varying
levels of functionality. I must admit that I am somewhat
disappointed in the lack of progress made in portable terminal design,
especially with hand-held units. If you think 386 processors, DOS
operating systems, and monochrome displays are ancient history you
better think again as these are the specs of many of the hand-held
portable data collection devices available today. On the plus
side, costs have come down over the years and I'm hopeful that more
quickly evolving technologies being developed for devices such as PDAs
will soon make portable data collection terminals smaller, lighter, and
more functional.
Batch versus RF.
Batch terminals are used to collect data into
files on the device and are later connected to a computer to have the
files downloaded. RF terminals use radio frequency waves to
communicate live with the host system or network. While batch
devices were heavily used in the past and still have viable applications
today, the introduction of wireless standards has made RF
technology much more affordable and easier to maintain and implement.
Hand-held devices.
As previously mentioned, I have been less than
impressed with advances in hand-held devices. I should also say
that I have a lot of problems with the basic nature of hand-held devices
themselves. First of all, "hand held" implies that you will be
using one hand to hold the device. Well, in most warehousing and
material-handling environments this is a problem since that hand can no
longer be used to handle materials or operate controls of
material-handling equipment. In addition, hand-held terminals generally
have very small LCD displays that are usually difficult to read as well
as very small, confusing keypads that are difficult to enter data into.
This doesn't mean that these can't be valuable tools in your operation,
only that you need to be sure to consider all the factors when
implementing this type of technology. Hand-held devices often come
with integrated bar-code scanners (as shown) however, they can be used
without a scanner or with a separate scanner.Hand-held Tips:
- The standard hand-held device design (like that shown) have little use in a warehouse outside of maybe a cycle count program. Instead, use the pistol-grip models which allow your workers to more quickly holster the device between scans to make use of both their hands.
- Keep the prompts as simple as possible. The prompts should show only the bare minimum amount of data necessary to perform the task.
- Minimize or eliminate data entry on keypads. As I said before, the keypads on these devices are difficult to use especially with alpha characters. Limit data entry to numeric data as much as possible and also eliminate the need to have to enter tabs or enter keys.
Vehicle-mounted devices.
Vehicle-mounted devices have several
advantages over hand held devices including larger screens (even up to
full sized screens), larger keypads similar to a standard keyboard on a
portable computer, and you can't drop, loose, or forget to charge them.
You're also more likely to find GUI user interfaces (Windows) on vehicle
mounted devices. When using a full-screen vehicle-mounted device,
integration can be much simpler as you can use your existing programs
designed for desktop computers (although you should still consider
simplifying the screens). Obviously you need to be performing tasks
using some type of a vehicle (lift truck, tug, cart, etc) to use a
vehicle-mount device. Generally, vehicle-mounted devices use a
separate wired or wireless bar-code scanner to input data. Tips
for using vehicle-mounted devices are similar to those for hand-helds
(simple prompts, minimize data entry) but you should also consult with
your vehicle manufacturer for recommendations on where to mount the
device to ensure safe operation of the vehicle.
Wearable Systems.
Wearable systems will likely have the most
growth in coming years. Currently offerings in wearable systems
are limited and include devices like
Symbol's
WS series (nicknamed the Gladiator) that is strapped to the
wrist/forearm and uses a small ring-type laser scanner for reading bar
codes, or the Talkman from
Vocollect
which is designed for voice systems (more on voice systems below).
Wearable systems provide the functionality of hand-held devices while
still allowing workers to use both hands. I should caution you
that several hand-held manufacturers have taken their hand-held devices,
put them in a fanny pack, connected them to a voice headset or ring
scanner and call them a "wearable system". While technically this
is a wearable system, I personally would not want to carry around the
added bulk and weight of a device designed with an LCD display and
keypad for 8 hours a day just because the manufacturer didn't want to
make the effort to design a wearable-specific device.
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