The buzzword in our industry is rugged, a word which I am the first to concede does a poor job of summarising the design considerations and lengths to which our tablets are tested. The truth is that no single word would describe everything that makes our tablets rugged. So what does it mean to be rugged?
Protection from drops is the number one voiced concern of business tablet buyers and owners who report that 21% of tablet failures are due to a fall (and presumably a greater percentage than this suffer minor damage due to drops that do not result in reported failure). First and foremost all our rugged tablet devices are tested for a minimum 1.2 metre (~4 foot) drop , considered the benchmark for mobile device ruggedisation. This will mean that a device can withstand a drop from an average person’s holding height, the height at which they regularly use a device. Many devices can withstand a much higher drop especially smaller and lighter devices such as Android devices and particularly our rugged smartphones.
Although we can unofficially throw a rugged Android phone across a room, the official testing involves dropping a device multiple times on all sides. Usually 50+ drops. The device must still work and not show any signs of damage such as cracks (scuffs permitted).
Here’s a drop test rig. Unfortunately having a person throw it about qualify the test fees so an elaborate machine dedicated to dropping things has to be used. You set the height, put the tablet on the shelf, stand clear, press a button on a remote and then the shelf releases the tablet. Not particularly fascinating in pictures and I assure you a video isn’t much more exciting after the first drop.
Temperature and humidity testing
An easily forgotten aspect of ruggedisation is resilience to high/low temperature and humidity. It may surprise readers that a whopping 40% of tablet failures result from extremes of temperature and humidity. This is not an insignificant statistic and worth noting that any after-market case added to a non-rugged device will have zero affect on protecting the device from these environmental factors. ‘Special’ environment chambers are used for these tests (a freezer would be too simple).
At Tablet Technologies all of our devices carry a minimum IP65 rating. On our latest Windows tablets and on most Android tablets and smartphones we offer an IP67 rating. However these numbered ratings, while a useful shorthand, don’t always have a very clear meaning to most of our customers and to people unfamiliar with mobile device ruggedisation.
IP65 testing involves a powder chamber test and a high pressure water test that involves what is easiest to describe as a water cannon. These tests ensure there is no ingress from dust or water. After the powder test the device looks like it’s been covered in thick snow. Then it gets a good wash down from all angles. To pass the test the device is opened up and photos are taken. There must be zero evidence of powder or water inside the device.
Here is a picture of the CONKER NX8 rugged Windows Tablet enjoying a good hosing (this test makes a Karcher pressure washer seem very reasonable).
To meet IP67 a device has to be submerged for 30 minutes at a minimum depth of 15cm. This test is usually done in a water tank with a water depth of 1 metre so that objects as large as 85cm can be tested below the 15cm depth mark. What this means is that our tablets that are generally only a few centimetres thick or less are actually being tested at a 1 metre depth. That’s a deep puddle!
Below is a picture of the CONKER NX8 Rugged Windows Tablet enduring an IP6x test. What you’re seeing is 2kg of talcum powder per cubic meter of chamber volume. An air current keeps the talcum powder in suspension during the test. These tests can last for hours and the picture below is after 3 hours of snow storm! A very ‘special’ fine powder is used so we’re told, Johnson’s baby powder wouldn’t do.
Testing for IPx7 is actually easier than IPx5. No water cannon required and not especially high tech. Operator instructions follow:
- Set yourself up for fishing
- Cast off the tablet
- Go for a lunch break
- Reel in your catch
IP68 specifies submersion at >1m depth for longer than 30 minutes. We can design for IP68 but do not currently do official testing for IP68 due to limited testing facilites and limited requirement for this level of certification. It’s all very well dropping your tablet in a swimming pool or in the ocean but unless you happen to have the device tethered the greater issue is likely to be recovering the device!
MIL-810 (Military testing)
MIL-810 is a series of standards relating to shock, vibration, wide ranges in temperature, humidity and sometimes also altitude. Although many aspects of MIL-810 are dealt with individually above most of our devices don’t have 3rd party MIL-810 certification because the target market doesn’t qualify the cost or have concern for this level of certification. None the less we do have a range of tablets that carry MIL-810 certification for those customer groups that require it.