Environmental Standards: Is Your Military Display Tough Enough?
A high-quality military display is tough enough to withstand virtually anything the environment can throw at it. After all, it is intended for use in military applications, which typically involve extreme conditions. Unfortunately, not all displays are up to par in this regard.
Before investing in a new display, military personnel should familiarize themselves with features that make them durable under a variety of extreme conditions. Understanding the characteristics that make displays rugged, durable and battlefield ready is critical to finding a reliable and long-lasting product.
What to Look for when Choosing a Military Display that can Withstand Extreme Environments
Temperature
Military operations take place all over the world, in a variety of climates. The best military displays are designed to operate in temperatures as low as -40 degrees Celsius/Fahrenheit and as high as 71 degrees Celsius/158 degrees Fahrenheit and tolerate even greater storage temperatures. They should also remain operational when exposed to the effects of solar gain and temperature shock as defined in MIL-STD-810.
With specific regard to LCDs, extreme cold temperatures can cause latent video transmission which can drastically affect a crew’s responsiveness to an event. With advancements in lighting and circuit technology, experienced manufacturers today can overcome limitations commonly seen in the past.
Moisture and Debris
Moisture is an ever-present element which presents a host of challenges for electronics. Whether it is driving rain, high humidity, condensation caused by pressure differentials, or the innate nature in which the unit is installed, displays must be designed to eliminate the possibility of water ingress. A unit designed to meet the IP67 standard, submersion in 1 meter of water for 30 minutes, is more than adequate to protect against typical in-field installations. Typically encased in strong, corrosion-proof anodized aluminum, IP67-rated displays are also highly resistant to ingress of dust.
As with all electronic devices, displays generate considerable heat while operational. The temperature difference created between the ambient environment and the internal enclosure will undoubtedly cause condensation if not properly managed. Through the use of advanced gas transferring components, manufacturers today are able to equalize internal pressures and eliminate water vapor.
Extreme Shock
Display systems are comprised of many small components that are responsible for delivering video and communications without disturbances. Ballistic, gunfire, crash and transport shock levels commonly seen in the field, and as called out in MIL-STD 810, can expose these components to up to 40g of impact. Mechanical design and component selection are critical factors to ensure video transmission is uninterrupted.
Constant Vibration
Today's most resilient displays are designed to withstand constant vibrations of up to 5.2 G at frequencies between 5 and 500 Hz. The typical profiles defined in MIL-STD-810 require testing multiple cycles on three axes. By confirming this, personnel can ensure the display they use will continue to function optimally regardless of steady vibrations to which it is exposed.
Power Input Fluctuations
It is crucial to look for a rugged military display with built-in protection against a variety of power input fluctuation scenarios such as load dumps, reverse polarity, over voltage, under voltage and short circuit. Vehicle platforms in today’s defense industry present a wide range of variables, and selecting electronics compliant with MIL-STD-1275 can ensure the power fluctuations won’t negatively impact the device and mission.
Electromagnetic Interference (EMI)
One factor often overlooked in the search for a military display is electromagnetic radiation or lack thereof. Invisible to the naked eye, this radiation can wreak havoc on the entire vehicle system. To counteract the effect of this radiation, a well-designed display will include an EMI shield.
Displays, in particular, must control the amount of interference emitted through the front glass window, bezel keys, and connectors. In addition, they must have protection from outside devices which may project their own level of interference. Guidelines and test procedures can be found within MIL-STD 461.
A military display is one piece of equipment that simply can't fail while out in the field. With that in mind, it is crucial to choose a manufacturer who not only designs their products to survive the most extreme environments and conditions but also has validation experience.
The Importance of User Interface in Ruggedized Military Displays
Ruggedized Military Displays
In the search for first-rate military displays, durability and strength tend to be among the chief concerns. The display is likely to be put through extreme wear, tear and abuse, so consequently, it has to be capable of withstanding virtually anything that's thrown at it. Ruggedized displays are the answer because they are designed to endure just about anything, including severe temperatures, shock and vibration. While durability is crucial, user-friendliness matters, too. To that end, it is wise to invest in a display with a user interface designed to be intuitive, efficient and easy to navigate. In an environment where every second counts, it pays to purchase a product that won't leave users scratching their heads in the heat of the moment. Today's finest ruggedized displays include these attributes: State-of-the-Art Touch Screen Touch screens are the standard in today's electronic market, largely because they are inherently easy to use and understand. Capacitive touch screens are typically seen in the consumer market; these touch screens only work with conductive objects, such as your fingertip. Resistive touch screens provide the same benefit of allowing users to select and navigate applications quickly and easily but rely on a small amount of pressure to register the input. Resistive touch screens have higher sensor resolution, fewer inadvertent or "accidental" touches, and can register input from any object (including military gloves). Touch screens which communicate via RS232 or USB are the most versatile and will work with many different systems and applications.
Well-Designed Bezel Keys
The keys on a display should enhance the user experience ̶ not detract from it. Buttons that are too small, too difficult to press or otherwise poorly designed create major issues for users and increase the risk of making mistakes during operation. Bezel keys are angled or sloped downward around their edges, rendering them much easier to press and allowing for faster and more efficient data entry. The most advanced systems will have programmable bezel keys, giving users a customized display experience to reflect their specific needs. The recent trend to incorporate programmable bezel keys gives the user superior control of critical components such as camera and gun systems, maps, and features like image processing. These added keys allow integrators to omit additional components such as joysticks, keyboards, and pointer devices which ultimately reduces system costs, weight, power consumption and real estate demands.
Intuitive Layout
Just as certain elements on a web page are expected to be laid out in a certain way, the layout of a rugged display should follow a logical, intuitive pattern.Bezel key location, on-screen menu navigation and graphic configurability all contribute to a simple and easy-to-understand experience. Programmable graphics overlays for bezel keys allow users to customize the display by defining the specific system level control for that particular key. Each installation requires a different set of functions, and the in-field ability to program graphics overlays answers the ever-changing need. This ability can also dramatically reduce the need for training, documentation and erroneous button activation.
Night Vision Imaging Systems (NVIS) Compatibility
Those who rely on NVIS devices should select a display that is fully compatible with MIL-STD-3009. Today’s displays incorporate full brightness DAY modes, to take advantage of sunlight readable technologies, and NIGHT modes, to adapt to night vision devices without adversely affecting the performance of the critical device. Covert operations also require electronics to be equipped with a “Blackout” mode, which immediately eliminates all light transmission with the single push of a button. The most advanced systems encompass both day and night technologies to enhance performance at all times of day, for all types of missions.
Modular Design
When it comes to ruggedized military displays, one size does not fit all. Leading manufacturers understand the need for a flexible approach for easy customization and integration for all Vetronic applications. With a trend to move towards COTS designs, manufacturers leverage past experience and fielded technologies for modified products, all the while reducing lead times, NRE, and risk to quality.
Input Configurations
The most well-designed displays include a variety of inputs, allowing for use with multiple devices without the need for an adapter. Whether an HDMI, DVI, RGB, USB, RS-232, HD-SDI or another type of input is needed, users should make sure the display they buy offers a variety of options. Foremost manufacturers are beginning to include video inputs such as HDMI and Ethernet to accommodate the inevitable transition from analog to digital. Anticipating future system level requirements, customers are selecting electronics with the latest video input configurations.
Backward Compatibility
A rugged display which is both backward compatible and achieves the highest level of modernization means that legacy architectures don't have to be abandoned in order to stay on the cutting edge of technology. For land-based, aerospace or naval applications, a durable and field-proven display is a requirement, but so is one that's easy to use. Digital Systems Engineering combines rugged strength with the latest technologies to engineer solutions unmatched by any other. Contact DSE for a free engineering review and quote: (480) 515-1110
