Designing Rugged Computing Platforms for UGVs
While the military’s proliferation of unmanned aircraft, or drones, continues to grab the headlines, the deployment of unmanned ground vehicles (UGV) is also anticipated to expand based on their role in helping military operations become more agile, responsive and safe. Intensifying mission requirements for UGVs called for in Future Combat Systems (FCS) depends on their ability to cost-effectively contribute to significant increases in intelligence through reconnaissance, surveillance, and target acquisition, coupled with the ability to handle high-risk or labor intensive tasks and the efficient transporting of personnel and materials.
Initial UGV design progression was hampered because they were typically based on proprietary technologies due to quick deployment needs or servicespecific requirements. Helping to propel UGV innovation is the availability of continuing advancements in open architecture COTS computing platforms. Now, UGV designs can more easily meet a long and growing list of interoperability, modularity and communications requirements and autonomous operation capabilities.
Suppliers of proven COTS platforms continue to broaden their portfolio with a range of solutions to satisfy strict size, weight and power (SWaP) mandates while featuring the latest multi-core processors, technologies and intelligence capabilities. In addition, highly ruggedized platforms ensure land-based vehicles meet system reliability and maintainability goals with their ability to withstand harsh environmental conditions where shock and vibration, dust, weather, obstacles, terrain and even hostile electromagnetic and cyber environmental concerns are all constant issues. Hand-in-hand with harsh environments is the careful consideration of thermal load and system efficiencies to maximize battery life that result in the utmost operational availability.
UGVs have been used in thousands of counter-IED missions, which made them indispensible in Iraq and Afghanistan. While they have proven their worth in saving lives, the Department of Defense (DoD) has also directed that next-generation UGV solutions continue to progress and at the same time be 'affordable and cost-effective' in a time of decreasing budgets. Understanding the severe operating conditions UGVs encounter, the DoD has specified that these systems must meet or exceed identified reliability goals to ensure they can accomplish their missions once they’ve been deployed. Interoperability, too, is integral to the continued success of UGV missions.
Contributing to many of the aspects called out in the RS JPO UGS (Unmanned Ground Systems) Roadmap (http://archive.defense.gov/pubs/DODUSRM-2013.pdf ), advanced COTS-based technologies inherently reduce lifecycle costs across all systems due to their interoperability and modularity, improved communications capabilities and the ability to support complex integration of such systems as weapons payloads. In order for UGVs to provide the “leap ahead” payload, communications, sensor or imaging capabilities expected, computing platforms must be based on the latest multi-core processors. Available in a variety of form factors and based on existing MIL standards, today’s COTS solutions support the need for a common UGV architecture.
For example, the operational value of a UGV increases significantly if it can offer increased sensor capabilities or intelligent payloads combined with the ability to change or update any of these based on specific mission profiles. This highlights the value from modular plug-and-play payload capabilities that enable expanded UGV combat roles. Modular platforms enable the DoD to easily implement functionality and material improvements to deployed systems.
For UGV upgrades, built-in tests are not sufficient when a system becomes degraded or outdated. Modular systems make maintaining and replacing systems streamlined, especially in harsh battlefield environments where there are few infrastructure support resources. According to the most current UAS report to Congress, UGV systems must be ‘simple and supportable by the operators and maintainers in the field’ to maximize their usability and viability.
Persistent support of 24 hours or longer is an ongoing requirement, so battery power is seen as one of the biggest limitations of any unmanned vehicle. While there have been increases in battery technology and power management, computing platforms have also made improvements in operating efficiencies needed to further extend battery life. Increases in power to performance ratios improve system reliability and useful operational time, helping to extend autonomous use value. The processor roadmap identifies continued improvements to power and performance that are now presenting challenges to currently-available computing platforms.
A case in point are new pre-tested rugged box level systems based on Computer-on-Modules (COMs) that use mezzanine modules with a carrier board offering a modular building block solution. These MIL-standard systems facilitate UGV development by allowing use and reuse of low power, highly reliable technologies in highly ruggedized enclosures, these small form factor systems add significant value when partnered with processor upgradability.
Purpose-Built Platforms for UGV Classes
Today’s UGVs can be powerful force multipliers and intelligent additions to tactical operations. To accomplish these goals, the unmanned roadmap identifies a variety of low-cost, easy-to-operate and flexible vehicle types based on mission profiles. With literally dozens of specific UGVs defined and more on the horizon, each service branch has their own specific strategy for UGV deployments classified under field light, medium and heavy UGVs. Vehicle types cover the spectrum from heavy All Purpose Remote Transport Systems (ARTS) and medium Multi-function Utility/Logistics Equipment (MULE) vehicles to light man-portable vehicles such as the Dragon Runner and ultra-small “throwbots”. In the case of throwbots, these mighty wonders must be rugged enough to survive being thrown or dropped onto concrete, perform in the roughest terrain and offer extended battery operation, camera and video capabilities for reliable short-range reconnaissance. Unlike throwbots, medium sized MULEs can be fully or semi-autonomously able to carry several hundred pounds, thus alleviating field personnel or the need for remote control operators.
Uniting them, all UGVs are defined to critically support situational awareness with safety-critical operation, advanced robotics and efficient operator control functionality. This mandates consistently reliable performance from extremely robust computing platforms. To be considered for UGV integration, small form factor systems must be designed specifically to ensure rugged performance that comes from 100% extended temperature screening and being thoroughly tested for a broad range of characteristics as an integral part of the development cycle. Ruggedized computing system characteristics must provide efficient thermal management from components that include a rugged baseboard, power module, fully-sealed housing, appropriate I/O connectors and options for future customized I/O.
Rugged by design, today’s extended temperature COMs-based computing platforms deliver improved SWaP solutions at less than six pounds that meet many UGV type needs. Integrating the latest Intel x86 COMe modules, new computing platforms enable system performance to easily evolve with processor advancements by swapping out modules, therefore supplying longterm upgradability and maintainability within the Joint Forces definition. In addition to simplifying upgrades and helping developers avoid time-consuming design re-qualification, COMe modules can be switched out without affecting carrier board customization, which gives longer lifecycle support for customized systems. Also, the latest processors deliver high performance that can be integrated into small form factor systems for enhanced UGV image resolution, mission-critical communications and network throughput.
Importance of SWaP-C
UGV designs demand continual power improvements without adding additional size, weight and heat to the equation. Thermal management is a huge requirement the smaller the system is. Overheating degrades the integrity and reliability even within the well-designed system. Careful consideration of SWaP-C (Size, Weight, Power and Cooling) is a necessity. Ideal thermal design for a UGV would be to implement all of the required system functionality in a chassis that has been pre-certified for ruggedized operation such as one validated to meet the environmental requirements of MIL-STD-810G, rather than one just listed as “designed to meet.” This assures the systems’ ability to withstand specified extremes of temperature, vibration, shock, salt spray, sand and chemical exposure from a sealed and temperature-controlled enclosure.
Advanced thermal methodologies are needed for a UGV’s unique operating environment that frequently calls for processing-intense operation. Threatening reliable and continuous program execution is higher power consumption and a greater thermal footprint due to reduced idle time of the processor. Because thermal management options are limited in ever-smaller UGV form factors, it is essential that the processor be power conscious and offer efficient system operation to minimize the thermal impact on the UGV.
Future trends will pave the way for increased real-time analysis of multiple situations by single operators, while the UGV performs its assigned mission autonomously. Next-generation communications functionality will need to offer simple plug-and-play payloads that are easily and cost-effectively updated or upgraded with the ability to be Internet of Things (IoT)-enabled linking to worldwide enterprise gateway and data center assets. Connecting disparate devices from all authorized DoD systems will help expedite the delivery of missioncritical information for vital real-time decisions. DoD will continue to stress further reductions to size, weight, power and cooling of military platforms to improve mobility and accommodate new payloads while reducing costs.
High-definition sensors will be an ongoing need, and high performance embedded computing (HPEC) systems will be required to support multiple sensor and communications capabilities. For these UGV types, SWaP-C is critical where future HPEC platforms must have a common hardware and software-defined architecture so it meets open standard plug and play and reduced cost goals. HPEC is also seen as addressing future cloud computing, multilayer security and evolving communications requirements.
What is known is that UGVs will have an important and growing role in future ground missions. Enabled by computing technology advancements developed to push the environmental limits of unmanned systems, they are key elements in the support RS JPO UGS Roadmap. Extending the capabilities of ground operations and keeping combat units out of harm’s way, UGVs must continue to make mission-critical system survivability priority number one.
This article was written by Joe Eicher, Defense Business Development, Kontron (Poway, CA). For more information, Click Here .