Magazine

A C-language computer program implemented as firmware controls the operations of a microprocessor on a 3-by- 1-inch (approximately 76-by-25-mm) motion-control circuit board denoted a widget board. The firmware implements a serial communication interface according to the inter integrated circuit bus...

A report presents a theoretical study of a harmonic oscillator in homogeneous or nonhomogeneous externally applied electric and/or gravitational fields. The standard quantum-mechanical formalism for a simple harmonic oscillator, starting with the Hamiltonian and the associated creation and...

A report discusses algorithms for realtime planning of translation paths of multiple spacecraft flying in formation. The algorithm takes account of requirements to avoid collisions while operating within resource constraints (e.g., not calling for an acceleration greater than maximum possible) and...

A report proposes the development of a microfabricated, integrated colloid thruster as a prototype of devices for propulsion and control of the attitudes of microspacecraft. (In a colloid thruster, a beam of positively charged, microscopic droplets is extracted electrohydrodynamically from a column...

A report describes a prototype system interface assembly (SIA) that performs the functions of a compact, radiation-hard application-specific integrated circuit (ASIC) to be built subsequently. The SIA ASIC would be installed in a spacecraft, where it would function as a peripheralcomponent...

A report presents a theoretical study of the thermodynamics of an ultralow-temperature gas of fermions that interact with a gravitational field and with an externally imposed trapping potential but not with each other. The gravitational field is taken to define the z axis and the trapping...

A report discusses the continuing development of a normally closed, piezoelectrically actuated valve fabricated mostly by micromachining of silicon. The design and operation of the microvalve as described in the instant report are basically the same as those of the version described in...

A report presents a theoretical approach to designing a low-energy transfer of a spacecraft from an orbit around the Earth to ballistic capture into an orbit around the Moon. The approach is based partly on the one presented in “Low-Energy Interplanetary Transfers Using Lagrangian Points”...

A method of generating three-dimensional composite digital images can serve multiple purposes in technical illustration. The method was devised to accelerate and facilitate the design of new electric lights and receptacles for large buildings, and can just as well be applied to the design,...