Immersive engineering is coming into everyday use at Bell Helicopter Textron, Fort Worth, Texas, thanks to motion-tracking technology from Motion Analysis Corporation (MAC). Using a 24-camera Hawk Digital system and simulation-software tools, Bell Helicopter's research and simulation unit can put almost anyone inside its massive engineering and performance database-in lifelike 3D stereographics and real time.
Immersive engineering brings design, performance and operational data into the world of Virtual Reality (VR). The Bell Helicopter system-the Interactive Design Visualization Center (IDVC)-is used by designers, engineers and mission planners to show potential customers, pilots, maintainers and even air traffic controllers how a Bell Helicopter aircraft and its crew will perform.
Thanks to motion tracking, these users can literally move around inside of, and interact with the data. Motion Analysis, in Santa Rosa, California, is the world's largest manufacturer of high-performance optical instrumentation systems that measure and analyze the movement of objects. Movement is tracked in real-time with the extensibility to scale to multiple, independent, concurrent, live, full-body kinematic simulations.
Key applications include animation production for movie making, movement analysis in medicine and sports, and industrial measurement and control.
Bell Helicopter Textron, designs, builds and supports the most proven, most reliable, and best performing vertical lift aircraft in the world. With its revolutionary tiltrotor technology, it is redefining flight. Bell has delivered more than 35,000 aircraft to customers in more than 120 countries.
The IDVC was built surprisingly quickly, in just three months start to finish, by a team led by Steve Lewis, Manager of the Simulation unit of the Bell Helicopter Flight Technology Group. The room itself was fitted with its motion tracking facility and multiple moveable 8-foot displays in just a week by Lewis' team to meet a deadline for a Textron corporate leadership visit. The IDVC was upgraded to include a 9 1/2-by-19-foot rear projection system for wall-to-wall and floor ceiling viewing, including active or passive stereo of up to five independent video feeds.
The IDVC is portable both virtually and physically.
This allows users to work with motion tracking remotely, a significant advance over many similar systems, where bandwidth imposes severe constraints. This is especially important to Bell Helicopter as its operations are widely dispersed. The main civilian / commercial aircraft assembly operations are in Mirabel, Quebec, Canada. Its military assembly facility is in Amarillo, Texas, but suppliers and support operations are dispersed all around the world.
While hardware mockups may require hundreds of thousands of dollars annually for transportation, maintenance and storage, Bell Helicopter managers pointed out that they are of limited use outside of marketing activities. Conversely, the content used in virtual simulations for marketing is routinely used in support of many other efforts including research and development, supply chain management, manufacturing and product support.
In the IDVC, 10 to 12 CPUs are required to run the MAC motion tracking, VR system and displays. "Building the simulator on top of the Math Model helped us hold costs to stand up the IDVC to just $750,000," Lewis said. Half of that went for software and support and half for integration.
"If the data can be characterized as motion in 3D space, we can simulate it and work with it through the Motion Analysis system," Lewis said. "The idea of the IDVC is to characterize the physical phenomena that impact the design on an aircraft by motion expressed in terms of positions, rates, and accelerations." His personal tech background is vibration and frequency analysis in aircraft.
The inherent opportunity in any set of data, no matter what its size, is to make it more accessible. "Accessible" means making the data:
Therein lies the technical challenge that Bell Helicopter has addressed so successfully with MAC's motion tracking technology. To really put data to work in new and more effective ways requires that users be able to get inside the data as they suggest improvements and analyze alternatives.
As with solid models and other Computer Aided Design (CAD) files, those changes still go onto layers, but now they are made while nearly surrounded by the data-rather than peering at it on a computer screen. To make changes with Motion Analysis tools, users mimic what is desired in the theater-like motion tracking room. They can see themselves and anyone else in the simulation as dynamic digital representations known as avatars.
Engineering data is reused and applied to refine designs and performance to optimize missions and mesh the results with customer preferences. At Bell Helicopter, data from the Math Model is used for design refinements, aerodynamics, maintenance / repair / overhaul (MRO) operations and technical publications-even for reconstructing crashes.
"The IDVC lets us do a great deal more with all this solid model / CAD data besides designing and fitting parts," Lewis said. "For example, we can build up tooling on top of design intent, layer by layer, and then display as-produced surfaces. This is great for hand-offs between departments and for all sorts of analysis." In essence, VR and motion tracking make data come alive.
The Motion Analysis system at Bell Helicopter uses 24 motion-tracking cameras positioned at multiple levels around a darkened, theater-like room measuring 20 by 20 feet. Users wear snug dark blue or black suits with two dozen reflective white spheres or markers, on key body parts. MAC's Hawk cameras capture every movement and every change in orientation; its EVa Real-Time (EVaRT) software tracks objects and reconciles overlapping views whether there is one user or several.
The power of the Motion Analysis system still leaves Lewis's team a bit awed. Lewis said that "People come to us all the time asking if we can incorporate some new idea of theirs into the IDVC. The answer is almost invariably, yes. The concepts associated with motion tracking and analysis in virtual simulation, by themselves, have fostered completely new areas of innovation at Bell Helicopter."
IDVC users can run multiple scenarios concurrently and independently in a single, shared volume of space. In fact, Lewis added, "we have enough camera and analysis power for a 40-by-40-foot motion-tracking theater."
On screen, users see digital representations known as avatars of their heads and hands; the forefinger doubles as a pointer or wand. Every movement of each user's body, even bend angles of finger joints, is immediately and precisely replicated digitally and displayed. IDVC inputs include but are not limited to:
Users can enhance the IDVC experience with full 3D using stereographic head-mounted displays (HMDs). As in any other VR system, HMDs let each user see any other users as parts of the simulation. Each user's perspective on the data is unique and that perspective automatically adjusts to every movement, just as in the physical world.
Bell Helicopter's Flight Technology Group is the parent organization for the Simulation Group and the IDVC. Innovations by this Bell Team allow multiple environments using varied technologies and levels of fidelity to interactively address challenges and solve problems over the Internet. When first introduced in a design collaboration linking five different Bell sites with the MAC System in the IDVC, a key program leader described the new capability as "amazing" and added, "This is going to change our lives in terms of the way we communicate with the designers back in Fort Worth."
Lewis put that in perspective: A team of visiting officials from the National Aeronautics and Space Administration (NASA) "told us they have been trying to develop something like this since 1992."
Lewis's comment about using the IDVC for something other than "designing and fitting parts" is a major understatement. Three examples:
Bell has integrated motion-tracking capabilities into multiple design, analysis, and test activities. Using some emerging technologies and analytical techniques developed at Bell, analytical iterations can be calculated "on-the-fly" in the virtual environment. One idea is to enhance and extend CFD capabilities to make more productive use of wind tunnel tests that cost upwards of $50,000/day. Bell has also been able to integrate test data into the motion-tracking environment to enhance understanding of test results. Flight test loads, motions, temperatures, acoustics, vibrations, pressures, etc., can be superimposed on 3D models for comparison with analytical results or for independent evaluation. Essentially any type of data that have spatial characteristics can be better communicated using the immersive virtual environments of the IDVC.
Air traffic control scenarios were developed to verify to the Federal Aviation Administration (FAA) that tilt-rotor aircraft such as the BA609 would not disrupt established airport operations. Bell conducted numerous piloted and batch simulations alongside FAA officials to evaluate BA609 flight paths during normal takeoffs and landings in a highly heterogeneous airspace simulation.
Bell has integrated predictive, measured, and artificial intelligence data from the FAA tests into a combined air traffic control simulation in the motion-tracking environment. Another proposed use of the IDVC is to combine these air traffic control scenarios with motion tracking's live immersive interactivity.
"Inputs for us can be almost anything than can be digitized," Lewis observed. "It's all just content to us." This content includes radar feeds for air traffic control, FAA Monte Carlo analyses for allocating landing slots and terrain maps from various sources.
Remote learning for aircraft diagnostics, maintenance training, and collaboration over the Web were also simulated. This time live 3D immersive interactivity was used to graphically demonstrate whether an additional radio will fit and not block access to any other components crammed into the nose of a helicopter that need regular service. This is very important to Bell Helicopter as it has a reputation to maintain. It has been named No. 1 in customer support by Professional Pilot magazine for 13 years in a row.
This simulation shows displays and monitors (front and back), air-conditioning ducts, radio connection sockets (power, control, antennas, displays, etc.), and Global Positioning System (GPS) navigation.
IDVC and motion tracking have brought great benefits to Bell Helicopter in terms of speeding up the use and reuse of complex data. "What users get from IDVC is better access to more data sooner to a good approximation of the ideal or perfect solution, and which can be easily communicated," Lewis said.
Many other ideas are in the works, some of them with the potential to transform the way design evaluation and testing are done at Bell Helicopter. Simulations and motion tracking in the IDVC can be used to:
In conclusion, Lewis observed that "sometimes with these simulations we even outstrip our own imaginations with what we can accomplish. Motion-tracking from Motion Analysis gives us powerful, proven and robust tools to use with our Math Model in overcoming everyday, real-world challenges."
Until very recently, most aircraft simulation was not digital or virtual but physical, as in physical mockups. Mockups have many shortcomings and systems like Bell Helicopter's Interactive Design Visualization Center (IDVC) with motion tracking were developed to find remedies.
"No matter how good they are, physical mockups don't really let you suggest and evaluate changes concurrently and in near real-time," said Steve Lewis, Manager of the Simulation unit of the Bell Helicopter Flight Technology Group.
There are two other alternatives to physical mockups, he added. One is loading AVI files onto CDs and distributing them by sneaker-net. It's digital graphics "but you only get one point of view while IDVC gives you many, he explained, and without motion tracking you have no real-time control of whatever motion you are working with." And finally there is just releasing the job unanalyzed to production or to the field "with guess and hope and redo later. This leads to huge rework costs eventually, almost all of them easily avoided."Copyright 2008, MINDFEED Marcomm, Santa Fe, N.M., USA