Rugged devices are a hugely important tools available to field service organisations to empower their engineers with mobile tools that are designed to survive the rigours of remote working environments. However, for the uninitiated, there can be...
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Nov 06, 2018 • Features • Hardware • Enterprise Mobility • field service • fit-for-purpose • IP ratings • Rugged laptops • rugged tablets • Service Management • Capacative vs Resistive • Field Technologies • MIL-STD810G • Rugged Mobile Device
Rugged devices are a hugely important tools available to field service organisations to empower their engineers with mobile tools that are designed to survive the rigours of remote working environments. However, for the uninitiated, there can be a bewildering amount of terms used by rugged manufacturers (and increasingly their consumer-focused cousin) so let’s take a quick refresher of some of the key language used in the world of rugged...
With no shortage of devices to choose from, deciding what’s best for your service operation is no easy task. Fit-for-purpose should be the starting point for any deployment, say the experts.
Indeed, the first question any company should ask when looking for new devices for their engineers or technicians is “what tasks will the device be used for?”
Mobile devices in field service are mission-critical – they are not just “nice-to-have”, they are the lynchpin of your operations essential to the efficient running of the operation. Ease-of-use of can have a big effect on productivity and user-acceptance – would an integrated barcode scanner, for example, be better than a more fiddly-to-use camera?
"The mobile device is more than your service technician’s new pen and paper; it carries the job schedule, customer details and equipment data..."
Remember, once you’ve made the shift away from paper, there’s no going back – the mobile device is more than your service technician’s new pen and paper; it carries the job schedule, customer details and equipment data.
Your customers will become used to the higher service levels.
So, above all, the devices you equip your field workers with need to be reliable.
Can it survive the technician dropping it? Are the processor and memory up to running several apps at once if that’s required? Is the screen readable in strong light? Will the touchscreen work if it gets wet? Can it last a whole shift without recharging the battery?
Is it Fit-for-purpose?
Almost every rugged device you see will proudly boast the magical code MIL-STD 810G somewhere in the specs but what exactly does it mean and why is it just so important?
Well as you may well have guessed MIL-STD is actually short for Military Standard. In fact, it is an American military standard that although has it’s origins with the US Air Force is now upheld in a tri-service agreement between the US Army, US Navy and US Air force. However, the standard is widely adopted amongst commercial products that need to be able to hold up to rigorous environmental tests.
The G if you were wondering, relates to the current revision of the certification document and we have been at G since 2008.
General Program Guidelines
The first part of the MIL-STD-810G is a set of general guidelines that describes management, engineering, and technical roles in the environmental design and test the tailoring process. It focuses on the process of tailoring design and test criteria to the specific environmental conditions an equipment item is likely to encounter during its service life.
Laboratory test methods
The second element of MIL-STD-810G is focussed on the environmental laboratory test methods to be applied using the test tailoring guidelines described outlined in the general program guidelines.
With the exception of Test Method 528 (Mechanical Vibrations of Shipboard Equipment), these methods are not mandatory, but rather the appropriate method is selected and tailored to generate the most relevant test data possible.
The tests themselves are varied across a range of different environmental stresses which include:
- Temperature ranges
Tested to. Vs. Engineered to
One problem with MIL-STD 810G testing is that it can be very expensive and it’s important to remember that MIL-STD-810 is not a specification per se but a standard. A specification provides for absolute criteria which must be satisfied to “meet the spec”. MIL-STD-810 as a standard provides methods for testing material for use in various environments but provides no absolute environmental limits.
Therefore, some OEMs will skip the whole second part of MIL STD 810G (the actual testing part) yet still claim their devices are engineered to meet MIL-STD 810G standards.
Whilst such devices may well be more than capable of surviving the rigours of your field engineers toughest day, the simple fact is that they haven’t been actually tested to do so.
That said most of the dedicated rugged players within the space such as Janam, Getac, Panasonic and Xplore et al will all have their own internal testing facilities and will also often engage with a third party to validate their findings.
IP environmental ratings along with MIL standards (MIL-STD) are perhaps the most widely recognised yet also perhaps the least fully understood of the standard definitions of what makes a mobile computer or tablet rugged.
What the IP figures mean
IP ratings are defined by International Electrotechnical Commission (IEC) standards and tell you how well devices are sealed against dirt and moisture ingress and the level of protection components have against whatever is thrown at them.
IP ratings have two numbers: the first indicates the degree of protection against dust, dirt and foreign bodies entering the device while the second is about how resistant the device is to the ingress of fluid from drops, sprays and submersion. Ingress protection ratings can be affected by the number of ports on a device and whether they are sealed or open, by keyboard design and a number of other factors.
"If like me, you’ve ever spilt tea or coffee on a computer keyboard, you’ll know that water ingress can be the kiss of death to electronic components.."
For field service, the numbers to look out for on a rugged mobile device are “5” and “6” for dust protection and 4,5,6, or 7 for water or fluid ingress. (In comparison, consumer devices typically have a rating of IP42 or lower although high-end consumer mobile devices are frequently now seen to have IP67 ratings)
Both are important when assessing devices: if like me, you’ve ever spilt tea or coffee on a computer keyboard, you’ll know that water ingress can be the kiss of death to electronic components. Less dramatic but in the long term just as damaging are ingress of dust and dirt particles. They can cause keys to stick and generally penetrate causing damage to components.
While “6” is dust-proof, a “5” rating doesn’t mean the device will prove unreliable, just that it isn’t completely sealed against dust ingress. It’s worth noting, too, that complete sealing against water and dust ingress may increase internal temperatures which in turn might impact on processor performance.
There are more numbers for fluid or water ingress: a “4” rating signals protection from splashes, “5” against water from a nozzle, “6” will cope with more powerful water jets or sprays, while “7” means you can submerge the device in water and it will still survive.
Again, which is best for your operations depends on the working environment – for many field-service environments, a “5” rating and even possibly a ”4 “will be perfectly adequate.
In a world of smartphones and tablets touch-screens have become a universally understood means of interacting with a device.
Whether it is inputting data or simply navigating through an operating system, I would put a hefty wager on the fact that anyone reading this article is both familiar and comfortable with using a touch-screen device, such is the prevalence of the technology today.
Touch-screens are an important, even critical part of the user experience of almost all modern tablets and smartphones. Yet at the same time, the screen is of course the potential Achilles heel and an obvious weak spot in a rugged device. The balance therefore between delivering a screen that is sufficiently capable of withstanding drops and knocks, whilst maintaining high usability, is absolutely critical for a rugged device.
So let's look at some of the various options you may find in differing rugged devices when it comes to the screen and explore exactly what these options actually mean.
Almost certainly the biggest debate when it comes to screen choices in rugged devices is whether capacitive or resistive screens are better suited for the task. But what is the difference between the two?
The older of the two technologies is resistive which relies on pressure to register input. This pressure can be applied by your finger, a stylus or any other object – think of the handheld computers that many delivery companies use, often covered in ink because when the original stylus is lost, the delivery driver often just uses a regular pen to collect a signature instead.
Resistive touch screens consist of two flexible layers with an air gap in between and in order for the touch-screen to register input, you must press on the top layer using a small amount of pressure to make contact with the bottom layer. The touch-screen will then register the precise location of the touch.
Rather than relying on pressure, capacitive touch-screens instead sense conductivity to register input—usually from the skin on your fingertip but also from dedicated styluses.
"The biggest debate when it comes to screen choices in rugged devices is whether capacitive or resistive screens are better suited for the task. But what is the difference between the two?"
Because you don’t need to apply pressure, capacitive touch-screens are more responsive than resistive touch-screens. However, because they work by sensing conductivity, capacitive touch-screens can only be used with objects that have conductive properties, which includes your fingertip (which is ideal), and special styluses designed with a conductive tip.
Initially one of the big advantages of capacitive touch screens was that they enabled multi-finger gestures – perhaps the most obvious example is pinching or stretching a document to zoom in or out. However, resistive touch screens have also supported multi-finger input for about three or four years now also.
The big advantage resistive screens have over their capacitive counterparts is the fact that the operator can still use the devices whilst wearing gloves – as the input is dependent on pressure rather than the electrical current being completed through a conductive material such as a finger.
An additional benefit is that light touch, such as rain landing on the screen, won’t register so the devices are far better to suited to being used in the wet.
Both of these factors are of course particularly useful in a number of field service environments.
However, another key factor for rugged devices is of course reliability and durability and in this respect, capacitive touch screens have the advantage – especially in heavy use applications.
Resistive screens can have a tendency to eventually begin to wear down in frequently used areas. Such areas may be prone to becoming faded and may ultimately even become unresponsive. Also in terms of reliability, if a capacitive touch-screen does happen to become pierced or cracked it is still likely to function – think how many times you have seen someone using a smartphone with a cracked screen?
However, a break anywhere on a resistive touch-screen will often mean that it no longer works.
In terms of field service, this is a potentially huge advantage for capacitive screens as it allows for a field service technician to continue to utilise their device until they can get the screen repaired.
Ultimately, there are many different rugged devices available these days ranging from rugged smart-phone style handhelds through to fully rugged detachable laptops. As we mentioned at the beginning of this feature ensuring the devices you select are fit for purpose is crucial.
In order to do this, we advise getting a real understanding of how your field service engineers and technicians are doing their job - what environments to they work in and what is there workflow. Get them in to give you some input or get out there on some ride-alongs. Because, if you have an understanding of this you will find a device that fits your needs.
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