What is a Rugged Computer?

A rugged computer can operate reliably in harsh environments such as temperature extremes (hot and cold – generally in a temperature range of -40°C to 85°C with fan-less cooling with extended life time availabilities) – also where levels of vibration are prevalent and wet/humid or dusty conditions exist.

In support of resistance to humidity and dust – internal components often come with conformal coating. In the design phase, product life simulations around temperature, vibration and humidity stress testing are completed to help uncover operational vulnerabilities around the devices external housings, internal components and cooling arrangements.

The majority of ruggedized computers share an underlying design philosophy of providing a controlled environment for their installed electronics. Rugged computers are engineered with thought processes to provide specific features and characteristics around the following:-

In reference to the above, electronic components are selected for their ability to withstand higher and lower operating temperatures than typical commercial components. Provision of design around the reduction of cabling, addition of liquid cooling and heat sinks – and use of rugged materials are a ‘must’ to ensure performance in harsh environments. Features also include fully sealed keyboards to protect against intrusion by dust or liquids and scratch-resistant TFT screens (for HMI purposes) that are readable in direct sunlight.

In general, ruggedised or ‘harsh environment’ computers provide the same required design features as each other.  Both terminologies are generally interchangeable with each other; in short, they’re no different from each other and service similar needs in the majority of instances.

Specifically MIL-STD-810G CN1 (2014), a military standard, issued in 1962, which establishes a set of tests for determining equipment suitability to military operations.

A United States Military Standard that describes how to test equipment for electromagnetic compatibility.

a military standard for shock which applies to equipment mounted on ships, where two levels apply. Grade A items are essential to the ships safety and continued combat capability. Grade B items are for where operation is not essential to the safety and combat capability of the ship but could become a hazard to personnel, to Grade A items, or to the ship as a whole as a result of exposure to shock. Qualification testing is performed on a barge floating in a pond, where TNT is detonated at various distances and depths in the pond to impart shock to the barges.

IEEE Standard Microcomputer Environmental Specifications for Computer Modules

Computers in electrical substations used to concentrate data or communicate with SCADA systems follow IEEE 1613 “Standard Environmental and Testing Requirements for Communications Networking Devices in Electric Power Substations.”

(Potentially Explosive Atmospheres): Equipment and protective systems intended for use in potentially explosive atmospheres

“Railway Applications—Electronic Equipment Used On Rolling Stock”, provides an example of a tough non-military specification. It extends operating temperature range (−25 – +70 °C), resistance to humidity, shocks, vibrations, radiation – encountered in vehicle or airborne installations.