Modeling and Simulation: ‘Working With Systems That Do Not Yet Exist’

By EDWARD LUNDQUIST

Modeling and simulation (M&S) is a new reality in naval warfare. The use of mockups, scale models and computerized M&S reduces the risk involved in developing, building and testing new combat systems. With M&S, training is more available, effective and realistic, fostering rapid, less costly validation of future concepts and new rules of engagement.

M&S today plays a significant role in developing, testing and evaluating the Navy’s remote technology. Naval warfare increasingly relies on unmanned systems, such as unmanned aerial vehicles, and simulations can be created to exercise airspace coordination.

Simulation-based training, already widely used in the fleet, is becoming even more prevalent. New ships will have “Total Ship Training” embedded, wherein advanced training technologies will deliver information directly to the sailor onboard the ship, providing immediate access to learning in their work environment.

The Littoral Combat Ship (LCS) is being built with Total Ship Training Architecture that includes new simulation technology, embedded training and instrumentation systems for “anytime, anyplace” training, ultimately maintaining the mission-readiness of LCS crews.

Guy Purser, director of modeling and simulation and chief engineer for the Naval Surface Warfare Development Center in Newport, R.I., leads the center’s implementation and execution of Fleet Battle Experiments. “Simulation is an integral part of the experimental architecture,” he said, noting that the center’s systematic approach focuses on organization, doctrine, tactics, training and procedures.

In the training environment, elements that are constant, such as weapons performance parameters or “call-for-fire” procedures, can be varied in the simulation environment.

“We can simulate an extended-range munition round or Long-Range Land Attack Projectile, and simulate a launch platform and target. These rounds can travel 50 to 100 miles, presenting problems or issues we haven’t faced before because the weapons have such long range,” Purser said. “So, we also have to look at airspace deconfliction, joint fires command and control, [concept of operations] development, or where battle damage assessment will take place. In experimentation, we can vary the procedures and doctrine, or try different tactics, for example, to see which combinations give us the right mix.

“In the training world, these are constant; but in experimentation, we vary them all,” he added. “In simulation, you can be working with a system or systems that do not yet exist. We have to immerse people in a new, unfamiliar environment that we call Immersive Simulation Technology. From the beginning, you have to engineer what it is you are going to do. You have to place a new weapon in a new environment.”

But, how do you create such an environment?

The Weapons Analysis Facility (WAF) at the Naval Undersea Warfare Center, Newport, R. I., provides the Navy’s only capability for real-time torpedo hardware-in-the-loop simulation, which supports all heavyweight and lightweight torpedo variants across the full torpedo life cycle — from research and development, through performance assessment test and evaluation, into the operational in-service phase.

As an example, the warfare center’s Carlos Godoy cites the approximately 1,200 in-water runs conducted on the Mk50 and Mk48 torpedoes for each weapon to be developed and introduced into the fleet. The average cost of each in-water run is approximately $100,000.

However, according to Godoy, the Mk54 torpedo used the WAF for most of its engineering development (more than 1,000 runs) at a cost of $500 per run. WAF support during technical and operational evaluations reduced the total number of in-water runs to less than 80. This effectively reduced the overall program cost by approximately one order of magnitude over its predecessor, the Mk50.

The Navy is using M&S to develop and test other important weapons systems, such as the Advanced Gun System (AGS), which is the “main battery” for the proposed advanced multimission destroyer DD(X). The AGS is being manufactured by United Defense LP, of Arlington, Va., in its Virtual Integration Facility (VIF).

“The VIF is a tool we use to communicate with our customer, but our engineers use it to see how their designs work,” said Jim Schoppenhorst, director of DD(X) programs at United Defense. “The VIF is a physics-based model of the gun. It goes far beyond animation. It is a computer-aided design tool that models all the parts of the gun, and incorporates the actual physics of a real gun, such as inertia or strengths of materials.”

With a physics-based model, the engineers and designers can identify a part or component in the VIF, observe its operation, remove it virtually and test it out with various materials or alternate designs. Rather than manufacturing a new component for testing, the VIF allows the new part to be installed and tested virtually.

“With VIF, prototypes came within 2 percent of predicted performance,” Schoppenhorst said. “When we used to build prototypes by hand, we were lucky to get within 10 percent of predicted performance.”

The AGS required four years from finished concept to system design review. After United Defense was selected as prime contractor for the AGS, there was a requirement to reduce the weight and volume of the gun. The company replaced the twin-cradle design with a vertical loading system, a process that took just six months.

“We looked at key aspects of performance,” said Schoppenhorst, concerning the Long-Range Land Attack Projectile used on the AGS. “With our modeling and simulation capabilities, we conducted parametric modeling to determine the key drivers. We wanted to know what drove the end effects of range, warhead payload and accuracy.”

For example, United Defense designers wanted to see if an extra kick out of the barrel would give the projectile a boost in range. This resulted in a corresponding increase in the weight of the round to account for the additional steel around the rocket motor, which protects it from the firing charge.

After plotting the results of thousands of simulated firings with varied parameters, Schoppenhorst said, the result surprised them. Instead of a greater charge, it turned out that a reduced charge, and a lighter round that was able to withstand the lower energy charge, actually delivered the greatest range.

The 7-foot-long round is a GPS-guided, rocket-assisted projectile with a range of up to 100 miles. With the AGS and Long-Range Land Attack Projectile, the DD(X) would provide long-range precision naval fires to support fast moving expeditionary forces far inland.

Whether predicting optimum system requirements for torpedoes, reducing the risks in testing new combat systems or evaluating rules of engagement decisions, modeling and simulation is proving to be virtually better in every way. M&S is the new reality in naval warfighting, and its delivering real improvements in surface warfare every day.

Retired Navy Capt. Edward Lundquist is the director of corporate communications for the Center for Security Strategies and Operations, Anteon Corp., Washington, D.C., supporting the director of surface warfare on the Navy staff.