The Role of Engineering Simulation in the Evolution of Unmanned Aircraft Systems

Across all domains (land, sea, and air), the use of unmanned aircraft systems (UASs) has shown explosive growth and, as their value continues to be demonstrated, this growth shows no sign of slowing. However, the UAS industry must address a number of key challenges if it is to satisfy the future roadmap for UAS development and deployment outlined by its major client, the U.S. Department of Defense (DoD). These challenges include:

• Transition from mission-specific platforms to a reduced number of common platforms that can serve multiple missions across and in conjunction with different domains;

• Increased platform capability including all-weather flight, payload weight, speed, endurance (even ultra-endurance), point to point, survivability, and refueling;

• Increased payload capability that empowers advanced sensing, autonomy, swarming and teaming, weaponization, and electronic warfare;

• Reduced forward footprint to lower the manpower burden in the theater of operation;

• Development of effective micro-UASs for rapid tactical deployment;

• Expanded missions including strike, cargo, and medical evacuation; and

• Adaptability in a fiscally constrained environment.

Evolving Role of UAS

As the indispensible contribution of unmanned systems became clear, the DoD published the first Integrated Unmanned Systems Roadmap in 2007[1]. This document spanned all domains — air, ground, and maritime. The roadmap was updated in 2009 to quantify and qualify how unmanned systems can be optimized to support a greater set of missions, pinpointing areas of technology maturation that can be shared across all domains, and identifying technology enablers to foster collaborative operations. Some of the broader goals of this integrated roadmap were to identify opportunities for cost savings and to provide long-term strategic directions for the UAS contractor community. When the factors from each domain are viewed in concert with the integrated roadmap, several key trends emerge:

  • Transition from mission-specific platforms to a reduced number of common platforms that can serve multiple missions across domains;
  • Increased platform capability including all-weather flight, payload weight, speed, endurance (even ultraendurance), point to point, survivability and refueling;
  • Increased payload capability that supports advanced sensing, autonomy, swarming and teaming, weaponization, and electronic warfare;
  • Expanded missions including strike, cargo, and medical evacuation; and
  • A reduced personnel forward footprint with a single controller guiding multiple UASs and more autonomy during landing and takeoff.

Implications for UAS Designers and Suppliers

The rapidly expanding use of UASs demands equally rapid integration of new technologies into existing platforms. The speed with which missions and capabilities are being developed means design and integration cycles must be very efficient and right the first time. In an increasingly competitive environment, the companies that succeed will be able to rapidly satisfy the needs of the end user. In the near and medium term, this will require customization of products to fit a variety of platforms. In the longer term, these custom products will likely evolve into optimized, standardized, plug-and-play modules, and new capabilities will be developed to integrate in this way. This will require close cooperation and interaction between system integrators and component suppliers in a way that facilitates the design process without compromising the core intellectual property of either party.

Over the next five to ten years, to successfully integrate advanced capabilities into existing platforms, designers and manufacturers will have to focus on size, weight, and power (SWaP). Retrofitting will require a critical understanding of thermal management, shock, and vibration to ensure the solution is robust and reliable.

Further out, as products and solutions mature and become standardized, it will become more important to establish levels of reliability equivalent to those of manned aircraft and to extend the system lifecycle. Reducing the personnel forward footprint will demand improvements in system aerodynamics and system capabilities to support more autonomous takeoff and landing.

While the fiscal pressure on UAS development may not be as great as on other military programs, the current environment is constrained, and consolidation and commonality of UAS platforms will occur across domains.

The Role of Engineering Simulation

Based on historic trends that have been observed and the UAS roadmap laid out by the major users, several key design constraints in the development of future UAS platforms and payloads can be expected:

  • Very short development cycles;
  • Near-term design customization with little design precedent;
  • Medium- to long-term design optimization for standardization;
  • Increasingly complex missions with associated capability innovation and integration; and
  • Tightly controlled costs and a demand for right-the- first-time design.

Engineering simulation harnesses the power of computers with software that solves the fundamental equations of physics or those that are close approximations. This allows designers and analysts to create virtual representations of complete UASs and their payloads for design space analysis and optimization prior to physical testing.

Correct implementation of the technology has been verified and validated in a range of industry sectors, and the use of engineering simulation is, in some cases, mandated by regulatory bodies.

The technique is well established in the aerospace and defense community, since the leading engineering simulation software companies have been in operation for over 40 years. The benefits of leveraging the technology have been proven time and again. Independent research[2] has shown that bestin- class companies:

  • Meet quality targets 91 percent of the time, compared with a 79 percent industry average;
  • Meet cost targets 86 percent of the time, compared with a 76 percent industry average; and
  • Launch on time 86 percent of the time, compared with a 69 percent industry average.

The standout difference in strategy pursued by the best in class is the systematic use of engineering simulation regularly throughout the design process. In essence, consistently leveraging engineering simulation throughout the design process helps to drive double-digit improvements in quality, cost, and time performance when compared with companies that fail to do this.

Research performed by the U.S. DoD revealed the staggering impact that engineering simulation can have[3]. A threeyear study reported that “for every dollar invested [in the software and computing infrastructure to support simulation], the return on investment is between $6.78 and $12.92.” These are recorded returns of between 678 percent and 1,292 percent.

There is clear overlap among the quality, cost, and time pressures that the UAS design and development community faces and the benefits of engineering simulation. As UAS capabilities continue to grow ever more complex for individual projects, engineering simulation will add the most value when:

  • It is applied to all aspects of UAS design (requires fluid dynamics, structural mechanics, electromagnetic, and thermal simulation capabilities, not just one or two in isolation).
  • The interaction of the physics at a system level is included in the analysis (for example, fluid and structures for wing flutter, structures, and electromagnetics for load-bearing antenna design; structural and thermal for component thermal stress analysis).
  • The workflow is seamless, integrated across physics and with existing tools such as CAD and PLM.
  • Physics-based optimization is performed across the design envelope.

At an organizational level, engineering simulation tools need to offer more than technical capability. The unique nature of UAS designs and their lack of design precedent make it critical to capture the design process and intent. That way, it can be systemized and scaled for future application. Capturing and managing this engineering knowledge is best performed in the simulation tools themselves, rather than PLM systems, due to the unique nature of engineering simulation data. The ideal scenario is when the simulation tool performs the engineering knowledge management and provides the PLM system with only the right type of information as needed.

The close collaboration between OEMs and suppliers required for successful platform and payload integration demands easy exchange of engineering simulation data while mitigating mutual intellectual property and data security concerns. The engineering simulation software community has responded to these needs and, for some time now, has offered organizations the ability to manage remote repositories of simulation data and to control access rights.

Having considered the growing UAS needs of the DoD and the way the benefits of engineering simulation dovetails with these needs, it is clear that engineering simulation will be a foundational technology for the development of next-generation systems and platforms. The fit is so strong that those in the UAS community not using engineering simulation today are unlikely to be tomorrow’s UAS designers or suppliers.

This article was written by Robert Harwood, Ph.D., Aerospace and Defense Industry Marketing Director, ANSYS, Inc. (Canonsburg, PA). For more information, Click Here .

References

  1. Weatherington, D. (2007). Unmanned Systems Roadmap U.S. Department of Defense, 07-S-2293.
  2. Research Brief: The Impact of Strategic Simulation of Product Profitability; Aberdeen Group, June 2010.
  3. Determining the Value to the Warfighter, a 3-Year ROI Study. DoD HPCMO, 2010