Automated Data Collection (ADC) Basics

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.

Voice technology (a.k.a. Speech-based systems) has come of age in recent years and is now a very viable and desirable solution in warehouse and shop floor data collection applications.  Voice technology is really composed of two technologies. Voice Directed, which converts computer data into audible commands, and Speech Recognition, which allows user voice input to be converted into data.  Portable voice systems consist of a headset with a microphone and a wearable computer. 

The advantages of voice systems are hands-free and eyes-free operation that allows people to communicate with a computer the way people communicate with each other. Applications for voice systems include order picking, quality inspection, shipping, receiving, cycle counting.

Speech recognition capabilities have been gradually improving through better software and hardware, however, this is not yet a perfected technology.  To compensate for problems associated with speech recognition, you really need to limit the speech input to a fairly short list of keywords and phrases for commands, and primarily numeric characters for voice data input.  Alpha characters would have to be spoken phonetically ( Alpha, Bravo,Charlie, . . . Zulu) to maintain an acceptable level of accuracy.  Fortunately, many warehouse and shop floor tasks can be performed very effectively within these limitations.

Go to Accuracybook.com's Voice Technology Links

RFID

RFID, Radio Frequency Identification.  Refers to devices attached to an object that transmit data to an RFID receiver.  These devices can be large pieces of hardware the size of a small book like those attached to ocean containers, or very small devices inserted into a label on a package.  RFID has advantages over bar codes such as the ability to hold more data, the ability to change the stored data as processing occurs, does not require line-of-site to transfer data, and is very effective in harsh environments where bar code labels won't work. RFID is not without it's own problems , RF signals can be compromised by materials such as metals and liquids. 

A little RFID vocabulary:

Active tags are RFID tags that contain their own power source (battery) and have longer read ranges.

Passive tags are powered by the signal generated from the reader device.

Read/write tags can have their data changed.

Read only tags are programmed once and their data cannot be changed.

EPC (electronic product code) is a set of standards designed to utilize RFID technology for the tracking of individual items as well as cases and pallets. EPC is similar to UPC used for bar code tracking of consumer goods.

GTAG  (global tag) is an international RFID standard that can be used for general asset tracking.

RFID Reader, also known as an interrogator, is a device that reads RFID tags.

Although RFID technology is getting a lot of attention these days it still tends to be cost prohibitive for most inventory tracking applications.  As chip prices go down you will continue to see growth in the application of RFID, however, as in the case of 2D bar codes, many warehouse and shop floor application simply don't require this added functionality. The low cost 1D bar code will likely continue to be the technology of choice for many inventory tracking applications. More info on RFID is available at my RFID Updates page.

Go to Accuracybook.com's RFID Links

Optical character recognition (OCR)

For years OCR has been used in mail sorting and document management, but has had very little application in warehouse and manufacturing operations primarily because it is not as accurate as bar code technology.  While I don't necessarily see OCR entering the warehouse in the near future, I'm not ready to write off the technology.  As hardware and software improves we may see this "old" technology make a comeback.  The primary advantage of OCR is that it can read the same characters that a human can read, eliminating the need for both a bar code and human readable text on labels, documents, etc. It also provides the ability to input data from documents  that do not include bar coded information.

Light systems

Although some may argue whether or not a pick-to-light system is an ADC technology, the fact is they accomplish some of the same tasks.  Pick-to-light systems consist of lights and LED displays for each pick location.  The system uses software to light the next pick and display the quantity to pick.  Pick-to-light systems have the advantage of not only increasing accuracy, but also increasing productivity.  Since hardware is required for each pick location, pick-to-light systems are easier to cost justify where very high picks per SKU occur.  Carton flow rack and horizontal carousels are good applications for pick to light.  In batch picking, pick to light is also incorporated into the cart or rack that holds the cartons or totes that you are picking into (put-to-light).   See article on Order Picking.

Integration of ADC Technology

While hardware costs of ADC equipment continue to come down, the cost of integration will often prove to be the project buster.  Software and Integration costs will often be several times the cost of the hardware, especially in smaller operations where only a few devices will be used. 

Integration of ADC technologies is also far from standardized.  For example, when implementing an RF system with portable terminals, one integrator may create a program on the terminals that will write directly to the file on the host system, another may create programs on a separate server to do this, another may write or modify a program on your host system and use terminal emulation software, and another may use a screen mapping tool to reformat an existing program to be used on the portable device.  Make sure you do your homework and talk to several integrators to ensure you are getting the best solution.  Also make sure you participate heavily in equipment selection and program/process design (prompts, data input) to ensure you get a system that provides the highest levels of accuracy and productivity.

There are also integration tools available that allow non-programmers (you will need some pretty good computer skills though) to integrate these technologies with host systems.  These tools will not have the functionality and flexibility of a good custom written program but may be adequate for simple applications.

Warehouse Management Systems (WMS) often come with interfaces to specific ADC equipment.  If your looking to add ADC to your warehouse you may want to first look at a WMS (read my article on WMS).

One of the biggest mistakes made when developing an ADC project is that people approach ADC as an "all or nothing" project.  The end result being that the when the project is quoted it tends to come in too costly to ever get implemented.  There is rarely significant financial benefit to using the "big bang" approach to ADC projects, so start small with the processes that can best benefit from the application of ADC and add on other processes later.