28 October 2014
How standardising on connectors will enhance military equipment modularity
The world of military equipment was, for many years, the realm of specialist suppliers who maintained proprietary standards. But the market has opened up in recent years and, with it, has come a move from proprietary to open systems.
The idea behind this is not only to reduce costs, but also to promote compatibility. And interconnection is playing a major role in this approach. Both the UK and the US have developed policies which drive standardisation. In the case of the UK, it's the Land Open Systems Architecture (LOSA), of which GVA – the Generic Vehicle Architecture is part. In the US, the equivalent to GVA is Victory; short for Vehicle Integration for C4ISR/EW Interoperability.
Professor Bryn James is a senior fellow in the Defence Science and Technology Laboratory's (DSTL) physical sciences department and an expert on the GVA. He explained the thinking behind the approach. "The MoD started to put LOSA together for a number of reasons, but basically so it could take a platform view; making everything plug and play, modular and adaptable. It allows us to get things into service more quickly, to be updated, replaced and repaired more quickly. The MoD has spoken at length with the Victory program and maintains a dialogue."
Dave Jedynak, chief technology officer with Curtiss-Wright Defense Solutions and a member of the Victory working group, noted: "Victory is a standard for how to do things on vehicles, but it's not as wide ranging as GVA. It focuses on communications between different systems, which have typically been developed as 'stovepipe' modules."
He offered GPS as an example. "Many military vehicles have GPS for position, timing and so on – there can be up to eight systems, all requiring receivers and antennas. If you can get everything on a shared data bus, you only need one GPS – and it's also a good way to address size, weight and power (SWAP) constraints."
And the weakest link – physically and metaphorically – is the connector. Jedynak continued: "One thing which jumped out of GVA was the fact that it specifies connectors and which pins should be used for Ethernet signals; use a MIL-STD 38999 circular connector and do it this way for a single port, that way for two ports. So we said why don't we try the concept of standard connectors?
"This makes for easier design; one of the questions it removes from the design process is 'how do I pin out Ethernet?'," he added.
Prof James said it was difficult to say when the thinking behind the LOSA initiative started, but noted it was motivated by much defence equipment being bespoke in nature. "LOSA comprises three sections; along with GVA, there are the Generic Base Architecture and the Generic Soldier Architecture. GVA is the more developed and is available for download at www.dstan.mod.uk. The first issue was published in August 2010, with the latest version published in 2013.
"Within GVA, part 1 looks at infrastructure issues and that contains everything related to connectors for communications and power systems – Ethernet, USB, optical and so on. Part 0, meanwhile, covers the philosophy behind GVA. It doesn't just specify, there's also a dialogue and a discussion on the topics."
He said LOSA and GVA are founded on nine principles and offered two as an example. "The first principle is that designs must take account of previous MoD investments – for example, we know that MIL-STD connectors work well. The second is that it must be applicable to current and future systems, because we're not going to change everything. What we want to do is to stop different things being used in different platforms."
GVA compliant kit is now being rolled out as part of the Warrior Capability Sustainment Programme and the Scout armoured vehicle programme.
Jedynak agreed that the benefit of programmes such as Victory and GVA was that they bring commonality. "One of the things we are trying to do is to shrink systems, but connectors are becoming a limiting factor in this respect."
He also pointed to the broader economic benefits. "If we can focus on a couple of key components, we should be able to get the benefits of volume through manufacturers investing, for example, in better tooling. And, by having a standard connector for GVA and Victory, we can get broader benefits; once you choose a connector, it will be the same as used by everyone else."
His analogy is RJ45. "There's a standard plug and a standard port. By driving military connector standards toward this, it will help to reduce problems of incompatibility and uncertainty when it comes to integrating military equipment. And it's the same with USB; while there are thousands of USB devices, they are all specified to the same protocol."
Prof James said that GVA continues to be 'work in progress'. "We want GVA to do more," he enthused, "and we want to include more areas. For example, we are doing work in bringing hydraulic and pneumatic systems into the Architecture."
Whilst both programmes talk about copper interconnect, GVA also covers optical interconnect. "There are significant benefits of using optics," Prof James pointed out.
However, Victory is more limited in its coverage. "We generally talk about copper," Jedynak accepted. "If you choose to go to fibre, it's covered by Victory, but the cost is generally higher; particularly in ground vehicles."
Jedynak sees a benefit beyond the connector itself. "If you can accept the concept that you have standard connectors on a box, it could also mean that, in the future, we could have standard cabling within vehicles.
"It might mean that you would have a standard part number for, say, a 10m single cable terminated with MIL-STD 38999 connectors."