13,030 research outputs found
Advances in the proposed electromagnetic zero-point field theory of inertia
A NASA-funded research effort has been underway at the Lockheed Martin
Advanced Technology Center in Palo Alto and at California State University in
Long Beach to develop and test a recently published theory that Newton's
equation of motion can be derived from Maxwell's equations of electrodynamics
as applied to the zero-point field (ZPF) of the quantum vacuum. In this
ZPF-inertia theory, mass is postulated to be not an intrinsic property of
matter but rather a kind of electromagnetic drag force that proves to be
acceleration dependent by virtue of the spectral characteristics of the ZPF.
The theory proposes that interactions between the ZPF and matter take place at
the level of quarks and electrons, hence would account for the mass of a
composite neutral particle such as the neutron. An effort to generalize the
exploratory study of Haisch, Rueda and Puthoff (1994) into a proper
relativistic formulation has been successful. Moreover the principle of
equivalence implies that in this view gravitation would also be electromagnetic
in origin along the lines proposed by Sakharov (1968). With regard to exotic
propulsion we can definitively rule out one speculatively hypothesized
mechanism: matter possessing negative inertial mass, a concept originated by
Bondi (1957) is shown to be logically impossible. On the other hand, the linked
ZPF-inertia and ZPF-gravity concepts open the conceptual possibility of
manipulation of inertia and gravitation, since both are postulated to be
electromagnetic phenomena. It is hoped that this will someday translate into
actual technological potential. A key question is whether the proposed
ZPF-matter interactions generating the phenomenon of mass might involve one or
more resonances. This is presently under investigation.Comment: Revised version of invited presentation at 34th AIAA/ASME/SAE/ASEE
Joint Propulsion Conference, July 13-15, 1998, Cleveland, OH, 10 pages, no
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Perfect Solidity: Natural Laws and the Problem of Matter in Descartes' Universe
In the Principles of Philosophy, Descartes attempts to explicate the well-known phenomena of varying bodily size through an appeal to the concept of "solidity," a notion that roughly corresponds to our present-day concept of density. Descartes' interest in these issues can be partially traced to the need to define clearly the role of matter in his natural laws, a problem particularly acute for the application of his conservation principle. Specifically, since Descartes insists that a body's "quantity of motion," defined as the product of its "size" and speed, is conserved in all material interactions, it is imperative that he explain how solidity influences the magnitude of this force. As a means of resolving this problem, Descartes postulated an idealized condition of "perfect solidity" which correlates a body's "agitation" force (a forerunner of Newton's concept of non-accelerating, or "inertial" motion) with the interplay of its volume, surface area, and composition of minute particles. This essay explores this often misunderstood aspect of Descartes' physics, as well as the special function of idealized conditions in his collision rules. Contrary to those commentators who regard "perfect solidity" as a stipulation on bodily impact, this notion, it will be argued, is primarily concerned with the internal composition of macroscopic bodies, and only indirectly with their collision characteristics. Along the way, many of Descartes' hypotheses will be shown to display a level of sophistication and intricacy that, despite their essential incompatibility, belie several of the common misconceptions of Cartesian science
Computer aiding for low-altitude helicopter flight
A computer-aiding concept for low-altitude helicopter flight was developed and evaluated in a real-time piloted simulation. The concept included an optimal control trajectory-generated algorithm based on dynamic programming, and a head-up display (HUD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor symbol. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and advanced navigation information to determine a trajectory between mission waypoints that minimizes threat exposure by seeking valleys. The pilot evaluation was conducted at NASA Ames Research Center's Sim Lab facility in both the fixed-base Interchangeable Cab (ICAB) simulator and the moving-base Vertical Motion Simulator (VMS) by pilots representing NASA, the U.S. Army, and the U.S. Air Force. The pilots manually tracked the trajectory generated by the algorithm utilizing the HUD symbology. They were able to satisfactorily perform the tracking tasks while maintaining a high degree of awareness of the outside world
Research on computational and display requirements for human control of space vehicle boosters. Part I - Theory and results Final report, 1 Mar. - 31 Aug. 1967
Optimization study of computation and display requirements for human control of reusable orbital transport ascen
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