Modern weapon systems are designed to fight and deliver maxi mum firepower, but they lack the ability to carry large amounts of munitions aboard or to reload rapidly to perform sustained combat operations. Each combat unit must return to a resupply point for replenishment to keep it an effective fighting force. Of all these supplies, ammunition is perhaps the most critical, and the task of resupplying ammunition is becoming ever more complex.
Presently, the world’s most lethal main battle tank, the M1A1 Abrams, must be rearmed one round at a time through the top of the turret, while the Army's howitzers must load four separate components — fuze, primer, propellant, and projectile — for each artillery round. The M2 Bradley fighting vehicle's ammunition stowage and rearm methods need improvement to sustain intense combat operations. The Cobra and Apache helicopters must spend considerable time on the ground to rearm. The concept of rapid rearm and resupply requires integration and optimization of the combat soldier's needs in relation to his weapon and those of the logistician and his resupply system.
To enhance this critical element of warfighting, several advanced technology programs are underway at Picatinny Arsenal, N.J., to improve weapon system rearmament. New systems in development for armor, artillery, infantry, and aviation promise a new era of rapid battlefield rearmament.
Armor units resupply during lulls in combat, or when necessary to replenish combat loads. This generally occurs behind the forward line, and the preferred method is to rearm from a resupply vehicle. Rearmament is usually carried out in the open through the crew hatch, exposing the weapon and crew to overhead and small-arms fire. Studies by the Armor School indicate the combat vehicle is particularly vulnerable at this time, and the exposure time is significantly increased when in an NBC environment.
Meanwhile, new developments in ammunition and armor protection and continuing threat improvements in armor protection have dictated increased weapon and ammo performance. This results in heavier or more sensitive ammunition, such as the 120-mm combustible cartridge case round that was fielded for the Abrams tank. In conjunction with these concerns, developing a rearm and resupply system capable of efficiently supporting the armor system in the forward area is our major challenge. The Project Manager for Ammunition Logistics (PM-AM MOLOG) has established a program, the Future Armor Rearm System (FARS), to meet deficiencies inrearming armor units. The FARS program is intended to develop, integrate, and demonstrate technologiescapable of moving present and future one- and two-pieced ammunition from a rearm vehicle into the bustle of the future tank. This program is under the direction of the Project Manager for Ammunition Logistics, and includes representatives of the Human Engineering Laboratory, Oak Ridge National Laboratory, and Tooele Army Depot.
Concepts for handling and transferring ammunition were conceptualized in 1989, and a demonstration is scheduled in conjunction with the Advanced Tank Cannon (ATAC) System in FY 92 and the Tank-Automotive Command CATTB in FY 94. The concept calls for a module mounted on the rear of the MLRS medium-type chassis. A bearing and drive motor mechanism allow 360-degree rotation of the module. In the travel mode, the module boom is oriented over the chassis cab. The rotating module per mits the rearm vehicle to load ammo into the tank from either side or over the rear deck (see figure 1). Rotation of the module and manipulation of the extendable boom are controlled by an operator from the front seat of the vehicle cab. Using video and sensing devices, the operator can align the boom with the tank's rear rearm port, thus permitting the boom to "dock" with the tank. The operator can select and transfer ammunition from the cab.
A series of three rotary carousel magazine storage cells within the module hold either a projectile or two propellant charges for the new two-piece ATAC 140-mm ammunition. There are twenty projectiles in each of the lower two carousels, and forty propellant charges in the top carousel (see figure 2); thus each stack contains forty complete rounds. Stacks of carousels are to be placed in tandem allowing the module to hold 80 or 120, depending on the module length.
A single extractor mechanism with powered rollers (see figure 3) permits the removal of a cartridge component from any cell in the carousel. The operator moves the carousel until the desired component is above the extractor mechanism. The extrac tor can pass ammo from stack to stack, or from one cell to a lift table located in the module in line with the transfer boom (see figure 2). The lift table takes the component from the carousels, then moves in pitch and elevation to align with the conveyors located in the transfer boom. The conveyors move the ammo through the articulated boom to the tank, where it is passed through the docking port to the awaiting cell of the tank autoloader.
Exploring tomorrow's issues today, with emerging technologies, is just another way the Project Manager for Ammunition Logistics provides professional and imaginative solutions to ammunition logistics.
A source - magazine Armor, July-August 1991
Another hydraulic system developed at ORNL was the Future Armor Rearm System (FARS), shown in Fig. 2. The FARS was designed and built with the assistance of Tooele Army Depot. The FARS was developed to allow the Army to rearm its new M1A1 tanks without exposing the soldier to the hazards of the battlefield. The FARS hydraulically actuated arm served several purposes: (1) to dock with the empty tank; (2) to be a communication link between the tank and the FARS rearm vehicle; and (3) to transfer the ammunition between the tank and the FARS vehicle. Control of the FARS arm proved to be a challenge in achieving the fine motion required to dock with the tank rearm port. Management of the interaction forces between the arm and the docking port during contact was proven to be a hydraulic system challenge. -Ultimately, interaction forces were controlled by developing a compliant rearm port on the tank. Flexibility and low natural frequency would be a problem with the FARS arm if it were moved quickly. To avoid exciting the arm's structural dynamics, however, the joints are moved slowly.
Source - Hydraulic Manipulator Design, Analysis, and Control at Oak Ridge National Laboratory. 1997.
D uring Operation Desert Storm, the ground war lasted only four days, rmnirmzing the need for U.S. armored forces to reload ammunition. However, if battle conditions had been different or if Iraq had made good on its threat to use nuclear, biological, and chemical (NBC) weapons, the process of manually reloading ammunition into armored fighting vehicles would have been a much more dangerous task. This problem was noticed long before Operation Desert Storm, however. Since the midl970s the U.S. Army has been looking at the difficulties of rearming armored and mechanized vehicles on the battlefield in light of various combat scenarios and computer models. Under some of these battle conditions, the necessity of manually reloading ammunition could limit the effectiveness of U.S. armor.
Currently, the world's most lethal battle tank, the MIAl Abrams, must be rearmed one piece of ammunition at a time through a hatch on top of the tank. Under battle conditions, when the tank is running low on ammunition, the tank commander asks the base to send a Heavy Enhanced Mobility Tactical Truck (HEMTT, pronounced him-it) to meet with the tank well behind the fighting line. When the tank and HEMTT meet, the tank hatch is opened, the HEMTT crew and tank crew dismount, and ammunition reloading begins. Crew members remove the tank ammunition from storage cans and pass it up to the top of the tank where other soldiers lower it down through the hatch. Inside the tank, a soldier places the ammunition into storage honeycombs. Under the best conditions, this procedure is a tiresome task; under battlefield conditions it is also dangerous because the crew and equipment may be exposed to deadly weapon fire and NBC agents.
ORNL's Role
An ORNL group is part of a national team working to improve the safety and efficiency of this essential element of armored warfare by developing critical technology for automated reloading of armored vehicles. This technology will be demonstrated using the Future Armor Rearm System (FARS). Under the project guidance of ORNL's Robotics and Process Systems Division (RPSD), staff members from RPSD, the Central Engineering Division at Martin Marietta Energy Systems, Inc., and ORNL's Plant and Equipment Division have joined together to help develop automated reloading technology.
The development of the FARS technology is sponsored by the U.S. Army's Project Manager for Ammunition Logistics (PM-AMMOLOG) through the Work for Others Office. The charter of PM-AMMOLOG is to identify logistics problems in the U.S. Army's ammunition chain and find solutions. Ammunition reloading for heavy armored systems is a proven logistical problem within the Army's armored systems. "The FARS program," says project sponsor Nelson Gravenstede, "is intended to develop, integrate, and demonstrate technologies capable of moving ammunition from a rearm vehicle into the tank."
To develop and demonstrate the FARS technology, PM-AMMOLOG has put together a team consisting of personnel from ORNL and several other Army facilities. The team members were selected based on their individual expertise. The ORNL group was chosen based on our experience with robotic and remote systems, our advanced controls and integration capabilities, and our ability to design systems to operate in hazardous environments, such as nuclear fuel reprocessing facilities and outer space. Other team members include the Human Engineering Laboratory at Aberdeen Proving Ground, Maryland, and the Tooele Army Depot at Tooele, Utah. We are also collaborating with Benet Weapons Laboratory of Watervliet, New York, designer of the autoloader that will fit inside the advanced tank. We are working with these groups to develop the many subsystems of the FARS automated reloading system. ORNL is responsible for the ammunition handling and storage system, the overall controls, systems integration, and final technology demonstration.
A Look at the FARS
The F ARS will consist of a tracked, armored chassis and a specialized mission module. The mission module will house systems for storing and transferring ammunition into the tank bustle. Automated reloading, which will be demonstrated with FARS technology at ORNL, will not only ease the manual burden on the soldier but will also provide a safer, faster, and more efficient means of reloading heavy armored systems. The use ofF ARS technology will eliminate the possibility of exposing soldiers to enemy fue or NBC agents during the reloading operation.
With the F ARS technology, when a tank is running low on ammunition, the tank commander will communicate that need to the base, which will send a F ARS to meet the tank. Because the F ARS will be on a tracked chassis, it will be able to negotiate the same sort of terrain as tanks, and, with its armored protection, the F ARS will be able to meet the tank closer to the fighting line than the HEMTT. The FARS operator will approach the tank and dock the transfer arm to the port located on the tank bustle. While performing the docking operation, the operators will stay safely inside the FARS cab, relying on camera viewing and joy-stick control of the transfer arm to remotely guide it. Once the docking is completed, the connection between the tank and the F ARS will be purged to remove any possible contamination by NBC agents during reloading, and a communication link with the tank will indicate when ammunition transfer can begin.
Ammunition will be housed in the FARS in individual storage cells. These cells will be mounted on a rotating carousel to allow access to any desired type and sequence of ammunition. The tank commander will be able to choose from several types of ammunition, depending on the nature of the target. For example, different types of ammunition are fired at heavily armored and lightly armored targets. When the tank commander specifies the desired combination of ammunition, the PARS will send the ammunition from the carousels to a lift table and through the transfer arm into the bustle of the tank. Once inside the tank, the round will be transferred into an autoloader mechanism that will store ammunition and feed it into the main gun.
Benefits of Automated
Reloading Technology Automated reloading technology being developed will provide many benefits over the current manual method. It will increase safety, reduce the size of armor support crews, and increase the battlefield availability of armored fighting vehicles.
Soldier safety will be improved because crews from both vehicles can remain under full armor protection during the entire reloading process. The technology also protects the systems from NBC contamination. Also, the soldiers are less vulnerable because automatic reloading is faster than the current method.
The second main area to benefit is crew size. The current method is labor intensive and lengthy. Soldiers from both crews must dismount and handle the ammunition as they move it from HEMTT storage, to the tank, down the hatch, and into the tank storage system. Automated ammunition reloading will reduce crew size because, once the PARS leaves the supply base, the ammunition never again has to be manually handled.
The third major benefit of automated reloading is improved battlefield availability for the fighting vehicles. Because the automated reloading vehicle is armored and tracked, it can move closer to the fighting line than the current reloading vehicle. The goal for the entire automated reloading sequence is 10 minutes or less, a significant improvement over the current manual method. Combining the increase in loading speed and the ability to perform reloading operations in closer proximity to the fighting line would result in approximately a 20% increase in the number of tanks on the battlefield.
Demonstration of FARS Technology
Although the FARS concepts apply to a fully developed rearm vehicle, the demonstration will concentrate on the critical areas of technology. A fullsize advanced tank will be included in the FARS technology demonstration, which will take place at ORNL in the fall of 1992. The FARS will approach, dock, communicate, and transfer ammunition into the tank's automated loading system. The technology developed with the FARS will feed into the Army's Advanced System Modernization program for the Future Armor Resupply Vehicle as a fielded system. The FARS team members have dedicated many hours of company and personal time to the project. Bob Oliver of the Central Engineering Division made scale FARS and tank models on his own time. These models have been used in briefings to top Army offtcials and others. For his initiative and effort, Oliver received special recognition from the PM-AMMOLOG Deputy Director. "Building military models has been one of my hobbies for many years," says Oliver. "Being named principal engineer for a full-scale prototype like this has been the highlight of my career at ORNL."
The FARS project results will demonstrate a variety of new and advanced technologies for the Army community. The control system currently under development will enable the F ARS operator to access any desired piece of ammunition by coordinating the various systems into an integrated operation. Rick Glassell, an RPSD controls engineer, has helped design the control system for the FARS. "Developing the controls system required to coordinate this many different operations has been a challenge," says Glassell. "Communicating with the tank and remotely controlling the ammunition transfer ann are two of the major goals we are working on for the demonstration."
The ammunition handling and transfer system, which was designed by ORNL, is the first of its kind to be able to remotely handle ammunition produced using the Army's advanced combustible-case ammunition technology. The ability to remotely dock and communicate with the tank is also a technological advancement. Systems exist that assist with reloading specific types of ammunition; however, these systems require a soldier in the rearming loop to complete the operation. The fully automated FARS, from the storage cells to the firing of rounds from the tank's cannon, will be a technological first.
The Army plans to employ FARS technology after the year 2000 on its next generation of tanks. However, the advanced technology being developed by the FARS program will likely have applications in other areas of military rearming. The innovative application of advanced technology to F ARS has been a significant technical challenge. It has required a total integrated systems approach using a broad range of ORNL expertise and capabilities, particularly in remote systems, telerobotics, and advanced automation. The FARS team and ORNL staff members are strongly contributing to meeting the technology needs of the U.S. military.
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Technology for the Future Battlefield
Currently, the world's most lethal battle tank, the MIAl Abrams, must be rearmed one piece of ammunition at a time through a hatch on top of the tank. Under battle conditions, when the tank is running low on ammunition, the tank commander asks the base to send a Heavy Enhanced Mobility Tactical Truck (HEMTT, pronounced him-it) to meet with the tank well behind the fighting line. When the tank and HEMTT meet, the tank hatch is opened, the HEMTT crew and tank crew dismount, and ammunition reloading begins. Crew members remove the tank ammunition from storage cans and pass it up to the top of the tank where other soldiers lower it down through the hatch. Inside the tank, a soldier places the ammunition into storage honeycombs. Under the best conditions, this procedure is a tiresome task; under battlefield conditions it is also dangerous because the crew and equipment may be exposed to deadly weapon fire and NBC agents.
ORNL's Role
An ORNL group is part of a national team working to improve the safety and efficiency of this essential element of armored warfare by developing critical technology for automated reloading of armored vehicles. This technology will be demonstrated using the Future Armor Rearm System (FARS). Under the project guidance of ORNL's Robotics and Process Systems Division (RPSD), staff members from RPSD, the Central Engineering Division at Martin Marietta Energy Systems, Inc., and ORNL's Plant and Equipment Division have joined together to help develop automated reloading technology.
The development of the FARS technology is sponsored by the U.S. Army's Project Manager for Ammunition Logistics (PM-AMMOLOG) through the Work for Others Office. The charter of PM-AMMOLOG is to identify logistics problems in the U.S. Army's ammunition chain and find solutions. Ammunition reloading for heavy armored systems is a proven logistical problem within the Army's armored systems. "The FARS program," says project sponsor Nelson Gravenstede, "is intended to develop, integrate, and demonstrate technologies capable of moving ammunition from a rearm vehicle into the tank."
To develop and demonstrate the FARS technology, PM-AMMOLOG has put together a team consisting of personnel from ORNL and several other Army facilities. The team members were selected based on their individual expertise. The ORNL group was chosen based on our experience with robotic and remote systems, our advanced controls and integration capabilities, and our ability to design systems to operate in hazardous environments, such as nuclear fuel reprocessing facilities and outer space. Other team members include the Human Engineering Laboratory at Aberdeen Proving Ground, Maryland, and the Tooele Army Depot at Tooele, Utah. We are also collaborating with Benet Weapons Laboratory of Watervliet, New York, designer of the autoloader that will fit inside the advanced tank. We are working with these groups to develop the many subsystems of the FARS automated reloading system. ORNL is responsible for the ammunition handling and storage system, the overall controls, systems integration, and final technology demonstration.
A Look at the FARS
The F ARS will consist of a tracked, armored chassis and a specialized mission module. The mission module will house systems for storing and transferring ammunition into the tank bustle. Automated reloading, which will be demonstrated with FARS technology at ORNL, will not only ease the manual burden on the soldier but will also provide a safer, faster, and more efficient means of reloading heavy armored systems. The use ofF ARS technology will eliminate the possibility of exposing soldiers to enemy fue or NBC agents during the reloading operation.
With the F ARS technology, when a tank is running low on ammunition, the tank commander will communicate that need to the base, which will send a F ARS to meet the tank. Because the F ARS will be on a tracked chassis, it will be able to negotiate the same sort of terrain as tanks, and, with its armored protection, the F ARS will be able to meet the tank closer to the fighting line than the HEMTT. The FARS operator will approach the tank and dock the transfer arm to the port located on the tank bustle. While performing the docking operation, the operators will stay safely inside the FARS cab, relying on camera viewing and joy-stick control of the transfer arm to remotely guide it. Once the docking is completed, the connection between the tank and the F ARS will be purged to remove any possible contamination by NBC agents during reloading, and a communication link with the tank will indicate when ammunition transfer can begin.
Ammunition will be housed in the FARS in individual storage cells. These cells will be mounted on a rotating carousel to allow access to any desired type and sequence of ammunition. The tank commander will be able to choose from several types of ammunition, depending on the nature of the target. For example, different types of ammunition are fired at heavily armored and lightly armored targets. When the tank commander specifies the desired combination of ammunition, the PARS will send the ammunition from the carousels to a lift table and through the transfer arm into the bustle of the tank. Once inside the tank, the round will be transferred into an autoloader mechanism that will store ammunition and feed it into the main gun.
Benefits of Automated
Reloading Technology Automated reloading technology being developed will provide many benefits over the current manual method. It will increase safety, reduce the size of armor support crews, and increase the battlefield availability of armored fighting vehicles.
Soldier safety will be improved because crews from both vehicles can remain under full armor protection during the entire reloading process. The technology also protects the systems from NBC contamination. Also, the soldiers are less vulnerable because automatic reloading is faster than the current method.
The second main area to benefit is crew size. The current method is labor intensive and lengthy. Soldiers from both crews must dismount and handle the ammunition as they move it from HEMTT storage, to the tank, down the hatch, and into the tank storage system. Automated ammunition reloading will reduce crew size because, once the PARS leaves the supply base, the ammunition never again has to be manually handled.
The third major benefit of automated reloading is improved battlefield availability for the fighting vehicles. Because the automated reloading vehicle is armored and tracked, it can move closer to the fighting line than the current reloading vehicle. The goal for the entire automated reloading sequence is 10 minutes or less, a significant improvement over the current manual method. Combining the increase in loading speed and the ability to perform reloading operations in closer proximity to the fighting line would result in approximately a 20% increase in the number of tanks on the battlefield.
Demonstration of FARS Technology
Although the FARS concepts apply to a fully developed rearm vehicle, the demonstration will concentrate on the critical areas of technology. A fullsize advanced tank will be included in the FARS technology demonstration, which will take place at ORNL in the fall of 1992. The FARS will approach, dock, communicate, and transfer ammunition into the tank's automated loading system. The technology developed with the FARS will feed into the Army's Advanced System Modernization program for the Future Armor Resupply Vehicle as a fielded system. The FARS team members have dedicated many hours of company and personal time to the project. Bob Oliver of the Central Engineering Division made scale FARS and tank models on his own time. These models have been used in briefings to top Army offtcials and others. For his initiative and effort, Oliver received special recognition from the PM-AMMOLOG Deputy Director. "Building military models has been one of my hobbies for many years," says Oliver. "Being named principal engineer for a full-scale prototype like this has been the highlight of my career at ORNL."
The ammunition handling and transfer system, which was designed by ORNL, is the first of its kind to be able to remotely handle ammunition produced using the Army's advanced combustible-case ammunition technology. The ability to remotely dock and communicate with the tank is also a technological advancement. Systems exist that assist with reloading specific types of ammunition; however, these systems require a soldier in the rearming loop to complete the operation. The fully automated FARS, from the storage cells to the firing of rounds from the tank's cannon, will be a technological first.
The Army plans to employ FARS technology after the year 2000 on its next generation of tanks. However, the advanced technology being developed by the FARS program will likely have applications in other areas of military rearming. The innovative application of advanced technology to F ARS has been a significant technical challenge. It has required a total integrated systems approach using a broad range of ORNL expertise and capabilities, particularly in remote systems, telerobotics, and advanced automation. The FARS team and ORNL staff members are strongly contributing to meeting the technology needs of the U.S. military.
Source - Oak Ridge National Laboratory REVIEW, Vol.25, No.1. 1992