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Linear actuation using milligram quantities of CL-20 and TAGDNAT

Propellants, Explosives, Pyrotechnics

Tappan, Alexander S.; Basiliere, Marc; Ball, J.P.; Snedigar, Shane; Fischer, Gary J.; Salton, Jonathan R.

There are numerous applications for small-scale actuation utilizing pyrotechnics and explosives. In certain applications, especially when multiple actuation strokes are needed, or actuator reuse is required, it is desirable to have all gaseous combustion products with no condensed residue in the actuator cylinder. Toward this goal, we have performed experiments on utilizing milligram quantities of high explosives to drive a millimeterdiameter actuator with a stroke of 30 mm. Calculations were performed to select proper material quantities to provide 0.5 J of actuation energy. This was performed utilizing the thermochemical code Cheetah to calculate the impetus for numerous propellants and to select quantities based on estimated efficiencies of these propellants at small scales. Milligram quantities of propellants were loaded into a small-scale actuator and ignited with an ignition increment and hot wire ignition. Actuator combustion chamber pressure was monitored with a pressure transducer and actuator stroke was monitored using a laser displacement meter. Total actuation energy was determined by calculating the kinetic energy of reaction mass motion against gravity. Of the materials utilized, the best performance was obtained with a mixture of 2,4,6,8,10,12-hexanitro-2,4,6,8,10, 12- hexaazaisowurtzitane (CL-20) and bis-triaminoguanidinium(3,3' dinitroazotriazolate) (TAGDNAT). © 2010 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.

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Wheeled hopping mobility

Proceedings of SPIE - The International Society for Optical Engineering

Fischer, Gary J.

Sandia National Laboratories has developed a mesoscale wheeled hopping vehicle (WHV) to overcome the longstanding problems of mobility and power in small scale unmanned vehicles. The system provides mobility in situations such as negotiating obstacles in the vertical dimension and rough terrain that are prohibitive for other small ground base vehicles.

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Covert air vehicle 2003 LDRD final report

Callow, Diane S.; Salton, Jonathan R.; Fischer, Gary J.

This report describes the technical work carried out under a 2003 Laboratory Directed Research and Development project to develop a covert air vehicle. A mesoscale air vehicle that mimics a bird offers exceptional mobility and the possibility of remaining undetected during flight. Although some such vehicles exist, they are lacking in key areas: unassisted landing and launching, true mimicry of bird flight to remain covert, and a flapping flight time of any real duration. Current mainstream technology does not have the energy or power density necessary to achieve bird like flight for any meaningful length of time; however, Sandia has unique combustion powered linear actuators with the unprecedented high energy and power density needed for bird like flight. The small-scale, high-pressure valves and small-scale ignition to make this work have been developed at Sandia. We will study the feasibility of using this to achieve vehicle takeoff and wing flapping for sustained flight. This type of vehicle has broad applications for reconnaissance and communications networks, and could prove invaluable for military and intelligence operations throughout the world. Initial tests were conducted on scaled versions of the combustion-powered linear actuator. The tests results showed that heat transfer and friction effects dominate the combustion process at 'bird-like' sizes. The problems associated with micro-combustion must be solved before a true bird-like ornithopter can be developed.

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Long range hopping mobility platform

Fischer, Gary J.; Fischer, Gary J.; Spletzer, Barry L.

Sandia National Laboratories has developed a mesoscale hopping mobility platform (Hopper) to overcome the longstanding problems of mobility and power in small scale unmanned vehicles. The system provides mobility in situations such as negotiating tall obstacles and rough terrain that are prohibitive for other small ground base vehicles. The Defense Advanced Research Projects Administration (DARPA) provided the funding for the hopper project.

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Miniaturized robotically deployed sensor systems for in-situ characterization of hazardous waste

Fischer, Gary J.

A series of ``MiniLab`` end effectors are currently being designed for robotic deployment in hazardous areas such as waste storage tanks at Idaho National Engineering Laboratories (INEL) and Oak Ridge National Laboratory (ORNL). These MiniLabs will be the first ever multichannel hazardous waste characterization end effectors deployed in underground high level waste storage tanks. They consist of a suite of chemical, radiological, and physical properties sensors integrated into a compact package mounted on the end of a robotic arm and/or vehicle. Most of the sensors are commercially available thus reducing the overall cost of design and maintenance. Sensor configurations can be customized depending on site/customer needs. This paper will address issues regarding the cost of field sampling verses MiniLab in-situ measurements and a brief background of the Light Duty utility Arm (LDUA) program. Topics receiving in depth attention will include package size parameters/constraints, design specifications, and investigations of currently available sensor technology. Sensors include radiological, gas, chemical, electrolytic, visual, temperature, and ranging. The effects of radiation on the life of the systems/sensors will also be discussed. Signal processing, control, display, and data acquisition methods will be described. The paper will conclude with an examination of possible applications for MiniLabs.

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7 Results
7 Results