Researchers at the Georgia Institute of Technology have developed technologies to lower maintenance costs for the Navy and to automate more tasks at the factory. The scope of the institute’s engineering research has also grown from its origins in textiles, ceramics, and early helicopter—or autogyro—design. Today, student and faculty researchers in Georgia Tech’s Logistics and Maintenance Applied Research Center—LandMARC—are using the latest information technology to reduce the maintenance and logistics costs for aircraft, I transit buses, and emergency vehicles. The first project undertaken by LandMARC is expected to reduce the cost of maintaining the US Navy’s aging fleet of Lockheed Martin P-3 Orion anti-submarine aircraft by more than $1 million per year. Georgia Tech and Navy personnel are concentrating on improving the diagnostic techniques for the Orion’s engine-driven compressor because it is the airplane’s single most costly repair item. The compressor supplies air to several key aircraft systems, including internal pressurization, engine start, and air conditioning.
THE GEORGIA INSTITUTE OF TECHNOLOGY has come a long way since its three original researchers received a grant of $12,000 in 1934. Although Georgia Tech's staff has grown to more than 1,000 professionals endowed with over $100 million, its mission in Atlanta remains the same as in Depression days: to develop innovative solutions that will foster industry.
The scope of the institute's engineering research has also grown from its origins in textiles, ceramics, and early helicopter-or autogyro-design. Today, student and faculty researchers in Georgia Tech's Logistics and Maintenance Applied Research Center- LandMARC-are using the latest information technology to reduce the maintenance and logistics costs for aircraft, I transit buses, and emergency vehicles. Other students and faculty members at the Institute 's Advanced Technology Development Center have developed software algorithms for a robotic motion control system to reduce the labor required for materials handling and inspection.
LandMARC was begun a year ago. It borrows technologies developed for a variety of industrial applications, such as monitoring health of factory machinery, and integrates them to improve all aspects of logistics and maintenance, thereby reducing the overall cost of owning complex machines and vehicles. Those technologies include sensing devices, portable diagnostic instruments and computers, Internet protocols, airborne recorders, and mission-planning software.
The logistics center staff is made up of students and faculty from Georgia Tech's Schools of Electrical and Computer Engineering, Industrial and Systems Engineering, Literature, Culture, and Communications, as well as the College of Computing. They divide their research into four areas: integrated logistics, predictive diagnostics, supply chain management, and system sustainment.
The first project undertaken by LandMARC is expected to reduce the cost of maintaining the U.S. Navy's aging fleet of Lockheed Martin P-3 Orion anti-submarine aircraft by more than $1 million per year.
The P-3 Orion is a land-based, turboprop aircraft designed to conduct anti-submarine and maritime surveillance. Lockheed Martin Aeronautics Co. introduced the P-3V in 1962, basing its design on the L188 Electra airliner, to replace the aging P-2V Neptune aircraft that the Navy had used for anti-submarine surveillance.
After three major model changes to the current P-3 , the Orion is still the only land-based anti-submarine plane in the Navy's service. In April, the Bush administration offered up to 12 Orion P-3 aircraft to the Republic of Taiwan, and the Navy Aries EP-3 that was struck by a Chinese F-8 jet fighter, also in April near Hainan Island, uses the same airframe as the Orion aircraft.
Four Allison T-56 aircraft engines carry 11 crew members a maximum of 2,780 nautical miles on a single mission. The P-3 fulfills its sub-hunting mission by means of advanced directional frequency and ranging sonobuoys and magnetic anomaly detection equipment. A general-purpose digital computer monitors and integrates this data to display it for the P-3 's pilots, provides the pilots with flight information, and automatically launches weapons.
The P-3 packs a nine-metric-ton arsenal, including a Harpoon cruise missile, SLAM missiles, Maverick air-to-ground missiles, MK-46-50 torpedoes, depth bombs, mines, and rockets.
Lockheed Martin built the last P-3 in 1990; the average age of the Orions in Navy service is 26 years. Because the P-3s remained in service longer than their designers originally intended, maintenance costs rose accordingly. In fact, Department of Defense research estimates that maintenance represents more than 60 percent of the lifetimecosts of complex military equipment, according to Ron Wagner, a retired Navy captain and co-director of LandMARC. Wagner served as an aviation maintenance officer during his naval service.
Georgia Tech's LandMARC wrote a proposal to the Navy and won a contract to develop a decision support system that could help the service maintain its aging Orion fleet. "We helped the Navy find funding through the Office of the Secretary of Defense for the research and development costs of the P-3 logistics and maintenance system; the Navy will fund the implementation of the system," explained Gisele Welch, an electrical engineer and director of LandMARC.
Improving Compressor Diagnostics
Georgia Tech and Navy personnel are concentrating on improving the diagnostic techniques for the Orion's engine- driven compressor because it is the airplane's single most costly repair item. The compressor supplies air to several key aircraft systems, including internal pressurization, engine start, and air conditioning.
The need to keep as many of the Orions in service as possible discourages conducting time- consuming troubleshooting using technical manuals, for example, when pilots report a warning light on a compressor-associated system. By erring on the side of safety, the Navy replaces an estimated 40 percent of the P-3 compressors unnecessarily at a cost of approximately $4 million per year for the entire fleet of 225.
LandMARC has developed an electronic performance support system, or EPSS, to trim unnecessary repairs on the Orion compressor by 25 percent, or about $1 million annually, by taking some of the guesswork out of compressor diagnostics. "The EPSS integrates proven technologies, including lap top computers, to download data from on-board flight data recorders, then process and integrate the data into a Web-based system that technicians can use while troubleshooting and repairing the aircraft ," Welch explained.
The support system can combine the data from different sources into a single Web - based information source for repair technicians. This type of architecture will allow for future enhancement without a complete redesign
The Navy is using the support system to develop an electronic troubleshooting guide that will assist aircraft mechanics working on the P-3 compressors. This guide will enable Navy technicians to troubleshoot, fill out paperwork, repair faulty equipment, replace it, and test it faster, in order to return the aircraft to service more quickly.
Among the diagnostic tools being use d by the P- 3 researchers is the Firefly Flight Data Recorder, developed by Georgia Tech in 1998 to collect data from electronic warfare equipment on Lockheed Martin's C- 130J Hercules, a tactical cargo and personnel transport aircraft. The Firefly records data gathered from sensors monitoring the aircraft and its flight , runs them through algorithms, and instructs the Hercules' computer how to release its load of decoys to confuse hostile radar
"In the P-3 project, we would like to install the Firefly on the Orion to monitor how the pilot flew the aircraft and how that affected parameters such as compressor performance, to get a more accurate picture of equipment status," Welch said.
At present, the new maintenance program is laid out in storyboard fashion, similar to the sketches of scenes for a motion picture, and will be evaluated in July. The Navy hopes to implement the EPSS program sometime next year.
If the program reduces compressor repair costs, the Navy will likely adapt it to other major P-3 systems, including hydraulics and landing gear.
Maintaining Bus Fleets
In addition to the Navy project, the LandMARC researchers are looking for opportunities to improve the maintenance of aging buses and trains. They are speaking with the Metropolitan Atlanta Rapid Transit Authority about using advanced diagnostics to prevent buses from breaking down.
This kind of plan involves installing diagnostic equipment such as vibration and temperature sensors on each bus, then connecting these sensors to a data collection device during daily fueling periods to download diagnostic information collected the previous day.
"This would allow technicians to track important parameters, such as high engine temperatures and excessive vibration, to discover systems in need of inspection or maintenance," explained Gary O'Neill, a former aerospace engineering duty officer who commanded the Navy's depot in Jacksonville, Fla ., before becoming a co-director of LandMARC.
A vibration sensor monitoring the transmission system could forewarn technicians of an impending failure in time to prevent a breakdown.
A transit agency also could use this information to identify long-term trends to avoid problems. "For example, data collected from a bus struggling up a steep hill in summer could convince the transit authority to change its route," Welch suggested.
Another benefit of collecting data from b uses is that a transit authority can analyze its repairs to reduce its overall spare parts inventory by stocking parts based on need.
LandMARC believes that nurses and other health care professionals can use the EPSS it is developing for the P-3 to streamline treatment of patients. The Georgia Tech logistics center is discussing this possibility with the nursing schools at Valencia Community College and Seminole Community College, both in Orlando, Fla. Both colleges are major trainers of nurses and have access to hospital testing facilities
Economical Assembly Algorithms
Manufacturers would benefit from automating many operations, such as loading and unloading containers or machines, and inspection of finished goods, where it is presently not economical to use robots.
CAMotion Inc. is an independent company formed by three faculty members at the Advanced Technology Development Center at Georgia Tech to commercialize a suite of proprietary software algorithms for a robotic motion control system to reduce the human labor involved in performing those routine tasks.
"The software's capabilities will minimize the cost of the robotic systems themselves, making inspection and assembly automation affordable," said Steve Dickerson, chairman of CAMotion. Dickerson, a member of ASME, is a retired professor of mechanical engineering at Georgia Tech.
The automation software is built around three types of algorithms developed by students and faculty affiliated with Georgia Tech's Manufacturing Research Center. CAMotion licenses these algorithms from Georgia Tech, which holds the patents on them.
One is a vibration control algorithm that plans the trajectory of a robotic arm to eliminate unwanted oscillation. Damping vibration enables engineers to design less rigid robotic systems from lighter and less expensive components, as little as one-third the cost of traditional robotic systems, according to Dickerson.
A second, learning algorithm in the CAMotion software means that automated equipment could improve its performance to reduce dynamic error by analyzing previous mistakes . The third, a position estimation algorithm, combines inputs from accelerometers, encoders, and machine vision to pinpoint the equipment's position relative to its task, is a basis to optimize its movements to do the job
CAMotion implements its proprietary control algorithms on standard, Pentium-based PC motherboards that use real-time software extensions. This arrangement eliminates the need for additional motion control cards, each of which would be equipped with a microprocessor. In addition, using PCs enables a manufacturer to rein in capital costs.
Speeding Product Packing
In late 1999, Vulcan Electro-Coating Inc. of Birmingham, Ala., approached CAMotion for help in automating the inspection and packing of products. Vulcan electron powder coats automotive roof racks for parts manufacturers supplying Ford, General Motors, and Toyota.
Inspectors had four seconds to examine yard-long coated roof rack parts to ensure that there were fewer than three coating defects or protrusions, each no more than one millimeter in size. "Even using our best-trained inspectors, meeting the tight coating quality standards demanded by the automotive industry just wasn't practical," said David Boyd, a coatings specialist and president of Vulcan.
Loading up to 500 coated parts into cardboard containers was also onerous, repetitive work, "and with less than one percent unemployment in our county, we decided to automate inspection and packing," explained Boyd.
The coatings executive described the automotive specifications to Dickerson, who programmed the CAMotion software accordingly. "We purchased standard robotic components and built an inspection machine and a packing machine, then programmed them with the CAMotion software and delivered them to Vulcan at a total cost of under $100,000," Dickerson recalled.
Today, Vulcan workers place coated roof racks onto the loading section of the CAMotion inspection machine. A gripper picks up each part and moves it through the inspection station, which is equipped with a robot-controlled head consisting of illumination and vision systems . The vision systems are made by DVT Corp., another Georgia Tech spin-off company, founded by Dickerson in 1991.
The vision systems move over the yard-long roof rack in six stages, capturing up to 120 images in less than five seconds. The CAMotion software analyzes them to inspect paint quality.
If the part being inspected does not meet standards, it is moved robotically to another stack for further inspection or coating. Rack parts coated properly are lifted by the packing machine and deposited in a cardboard container that holds 500 parts.
The packing machine is basically an xz robot that lifts each part about 4 feet, moves it 5 feet horizontally, and deposits it in the box. "Because of the relatively long motion, the vibration dampening algorithm really pays off," noted Dickerson. "We only needed to provide the robot packer with two degrees of freedom because the containers are slightly larger than the parts."
Vulcan is beginning to phase out its current roof rack coating assignment for another that involves use of a different coating on similar parts. "We'll just reprogram the new inspection specification this entails on the PC," said Boyd.
CAMotion used its experience at Vulcan to refine its software and hardware designs. "For example, we structured our software differently to run on Linux, an open architecture, to enable us to make internal changes with more freedom than the original, Windows-based structure," Dickerson said.
In addition, the company developed the Remote Axis Serial Interface Device, basically a circuit board with microcomputer that controls the servo-motors and other nearby inputs and outputs in the robots after receiving serial commands from the Pc. The RASID is mounted near the robot system's servo-motors, thereby reducing the amount of wiring needed, and continuing to eliminate the need for costly servo-control cards.