Buying Rugged Hand-Held Computers

"Just don't call our computers PDAs," begs Mike Colwell, director of product marketing for Norand. While his company has been manufacturing rugged hand-held computers for very specific industrial applications since 1968, personal digital assistants (PDAs) as a concept are only a few years old, are typically classified as general-use computers for personal-productivity applications, and just as typically don't hold up well in the harsh computing environments that Norand sells to. They've given the whole hand-held-computer industry something of a bad name, one that's not necessarily deserved.

Because hand-held computers in industrial markets are constantly in operation during a workday as an e mployee moves through a factory floor or from one field location to another, their durability requirements are very different from a typical laptop or even a PDA. Hand-held computers get bumped. They constantly have their circuitry under much more stress than usual.

There aren't any industrywide certification processes for ruggedized computers, making it hard to compare systems. But all vendors will have test results from either their own labs or third-party test facilities. To make meaningful evaluations, ask for hard copies of the drop tests. Maybe your equipment will never be subjected to 200 drops from 6 feet, but you'll have a margin of safety if you choose a system that has. Vendors should also make available what the industry calls "shake-and-bake" tests -- high- and low-temperature variations, plus vibration-test results. All this durability comes at a price, but it will be worth it if your application requires computers to work in harsh environments.

"A lot of companies look at a rugged platform and then decide that they don't want to spend 10 percent or 15 percent more for it," says Tim Schmidt, principal for Encore Consulting Group. "But what's the return on the $150 to $300 you saved on the computer if you're down for the day because the system you bought failed?"

If the system has external PC Card slots, ask the vendor if the connectors are truly waterproof or only have rubber caps that your users will lose the first day out in the field. Just as critical is having enough expansion slots, so that users don't need to change cards (from loss or damage) in the field.

Extra batteries are another point of failure for rugged systems -- look for lithium-ion units, and make sure the vendor provides simple charging units for multiple batteries.

Be prepared to trade durability for weight. Schmidt puts the weight limit on a hand-held device at 4 pounds. "Telxon has just released a new rugged unit that weighs in at 4.8 pounds without mass storage," he notes. "I'm sorry, but peo ple will complain."

Other systems will compromise usability for increased ruggedness. Make sure that the hand-held device you select offers access to the peripherals you need -- for example, a standard keyboard at a decent price for diagnostics or standard floppy drives for downloading information.

Schmidt notes that just three manufacturers of rugged hand-held computers (Norand, Symbol, and Kalidor) have provided their customers with a convenient way to download information from a hand-held computer to a back-end database. All three companies provide what Schmidt calls depot docking stations , which let users dock hand-held computers overnight and have the data collected during the day be automatically transferred to a server. "The other companies still don't seem to realize that customers are crying for this capability," says Schmidt.

Some systems might be more rugged than you need, forcing you to make choices that don't make sense for your business. "Some manufacturers make a t otally enclosed case," says Schmidt. "But you need to ship the computer back to the manufacturer to add new PC cards. Do you really need that level of reliability?"

"My advice is to really put your specs together on what you want the equipment to do," says Schmidt. "All vendors will tell you that their systems are rugged. But is it easy to upload and download information? Do you have access to a keyboard when you need it? Can you connect easily with the network and with PC cards? Does the device give you enough expansion slots for the next two to three years? And can it do everything you need it to and still hold up to what your users will put it through? Act like you're from Missouri and say, `Show me.'"

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Shopping List

--  Lithium
-ion batteries

--  Simple
 recharging units for extra batteries

--  Acceptables
 weight

--  Waterproof
 external PC Card slots

--  Extra
 expansion slots

--
  Optional
 peripherals: keyboard, floppy drives, docking stations

--  Ease
 of upgrade/maintenance

--  Easy
 mounting on vehicle

--  Written
 proof of ruggedness, temperature, and vibration testing