As ground vehicles employ more electronic sensing, control and communication systems, design engineers are increasingly utilizing more commercial off-the-shelf (COTS) modules. Though COTS slashes development time and costs, it’s still difficult for many military users to find COTS boards that meet their low-volume demands for ruggedization and redundancy.
Sensing and computing systems in vehicles get more complex, so there’s increased interest in modules based on the VME and Open VPX, a successor to the venerable VME bus, created by the VITA Trade Association, according to several speakers at the recent Embedded Tech Trends conference. More military projects are adopting open architectures that offer a number of production-ready computing and sensing boards.
“Customers don’t even want to look at solutions that aren’t COTS,” said Bill Ripley, Senior Designer at Alligator Designs Pvt Ltd. “They don’t want to pay for development. Suppliers need to start designing products, not starting projects.”
Using COTS products can also help military system designers meet their need for fault tolerance. Standard architectures can make it easier to find modules that can work together to provide fault tolerance while still shrinking overall system size. That’s often accomplished by using elements like multicore processors that can be used for more than one task.
“They want redundancy, but they’re also trying to come up with a converged architecture where resources that can be shared are shared,” said Greg Rocco, MIT Lincoln Laboratory.
While VME and VPX provide standards that simplify design projects and foster competition among competing companies, many military design teams still find it difficult to transition away from customizing their requirements. Vehicles and user requirements vary widely, which can make it difficult to buy from a pre-designed product lineup.
“In the mil/aero market, people come in and tell us they need COTS, then they spend 20 minutes telling us why they’re not able to use it,” said Kenneth Brown, Program Manager at LCR Embedded Systems Inc. “We’re seeing growing demand for VPX, which offers infinite possibilities. With VME, there’s often not enough bandwidth or I/O capability.”
VPX is gaining popularity largely because it increases overall performance compared to its predecessor, VME. VPX also provides a number of different options created to provide enough flexibility to meet nearly any customer requirements.
“There are 81 slot profiles for 3U and 6U boards,” said Michael Munroe, Elma Electronic Inc. “If companies can describe their backplane requirements, they can use one of these templates.”
However, having flexibility can reduce the benefits of open standards, since connector positions and pinouts can be incompatible. There’s a push within VITA to reduce the number of user-defined pins in connectors. Engineers also need to consider their position and alignment.
“System designers want to ensure that connectors are in the same spot with the same configuration so when they get boards from different vendors they are truly compatible,” said Patrick Collier of NAVAIR.
The move to COTS comes as ground vehicles not only use more sensors but also employ higher resolution devices. It’s becoming a challenge for microprocessors to handle all that data, which may prompt a change from conventional microcontrollers to graphic processing units (GPUs) or other parallel computing architectures. Parallel processors are well suited to processing imagery and other sensor input.
“The next growth area is an increase in the number of pixels in cameras and use of more sensors like Lidar and gamma detection,” said Douglas Patterson, Sales and Marketing Vice President at Aitech Defense Systems Inc. “There’s so much data that CPUs aren’t keeping up. Some companies are going to Nvidia’s graphic processing units, which use many hundreds of simple cores to process images.”
There may be solid market growth even in vehicle systems that don’t require the latest technologies. Many military vehicles are aging, so replacements will help drive market growth for boards and systems that fit common platforms.
“There are 30,000 unmanned ground vehicles that need to be replaced in the next few years,” said Brian Arbuckle, Senior Market Analyst at IHS Markit. “That creates a need for systems with new sensors.”