Defence departments in countries across the world are challenging industry to reduce development time and cost.
As a consequence, MIL-COTS products are becoming more important. Consider the need for tactical intelligence in warfare. For the first time, technology is providing some ability for commanders to gain real-time insights and situational awareness 24/7. Such tools as unmanned aerial vehicles (UAVs) are gathering surveillance imagery that helps to find and neutralise insurgents and, perhaps equally important, identify those who legitimately live and work there.
Although the power requirements of each electronic device or system are different – fast delivery, light weight, unique packaging, heat and noise management, low voltages, high currents, fast transient response, high efficiency – they all need MIL-COTS power.
UAVs, which have been characterised as the biggest change on the battlefield since the introduction of gunpowder, can weigh a pound or so and be handheld or have a wingspan of 15 metres or more. They are designed to fly at altitudes of many kilometres and some can remain in the air for days. But, more important from a power point of view, is the payloads they carry.
In the air, the power solutions are dictated by the increasingly demanding requirements of the onboard electronics, which could include an onboard computer (eg, for image processing, autopilot, data acquisition/analysis, control actuation), sensors (eg, GPS receiver, gyroscopes, accelerometers), transceiver and cameras (eg, infrared, thermal imagers, low-light TV cameras, video cameras). Power requirements likely include MIL-COTS 28 V d.c. input (MIL-STD-704) with output of perhaps +5 V (eg, inertial sensors), +3,3 V (eg, computers, GPS) and +12 V (eg, transmitters). Power could be in the range of tens to hundreds of Watts.
In general, whether a MIL-COTS UAV system is in the air or on the ground, reduced SWaP (size, weight and power) – and compute-intensive electronics – are the order of the day. MIL applications, of course, have to be rugged and able to withstand severe environments, including shock and vibration and very high and low temperatures (Afghanistan temperatures, for example, can range from about 45°C down to -45°C).
The new, powerful Core i7 processor from Intel, for example, is already being used in many MIL-COTS applications. Power supplies must meet the requirements of the VR12 design guidelines in terms of response time, trim range and the amount of permissible droop. The Core i7 processor goes into sleep mode when there is no processing needed, and when it instantaneously wakes up, power must be immediately available. Clearly, with such a processor, fast transient response from the power supply is absolutely essential.
New MIL-COTS power solutions are available from Vicor to support such advanced technologies as those represented by UAVs and their ground systems, and they are small, lightweight, rugged, low noise, highly efficient and provide fast dynamic response. Specifically, for example, power solutions based on VI Chips can more easily be designed because they are small (1/16 and 1/32 brick footprints), lightweight (14 grams), rugged (encapsulated), highly efficient (95%), and have wide operating range (-55°C to 125°C) and fast transient response (1 μs).
Another advantage that these devices bring to military applications is the robustness of the design – they withstand enormous amounts of shock and the interconnect systems are very rugged. Because the regulation and isolation are split into two devices, they can be physically located in different sections of the end use, distributing the thermal load more efficiently and allowing for weight distribution.
For more information contact ECS, +27 (0)12 345 6132, [email protected], www.ecssa.co.za
© Technews Publishing (Pty) Ltd | All Rights Reserved
printer friendly version