Abstract:
A miniature Hall current plasma source apparatus having magnetic shielding of the walls from ionized plasma, an integrated discharge channel and gas distributor, an instant-start hollow cathode mounted to the plasma source, and an externally mounted keeper, is described. The apparatus offers advantages over existing other Hall current plasma sources having similar power levels, including: lower mass, longer lifetime, lower part count including fewer power supplies, and the ability to be continuously adjustable to lower average power levels using pulsed operation and adjustment of the pulse duty cycle. The Hall current plasma source can provide propulsion for small spacecraft that either do not have sufficient power to accommodate a propulsion system or do not have available volume to incorporate the larger propulsion systems currently available. The present low-power Hall current plasma source can be used to provide energetic ions to assist the deposition of thin films in plasma processing applications.
Abstract:
Example devices and methods of tongue stimulation for communication of information to a user are disclosed herein. In an example, a tongue stimulation device may include a body configured to be placed entirely within a mouth of the user and atop the tongue of the user. An array of electro-tactile elements may be distributed on the body, wherein each of the electro-tactile elements is configured to stimulate an area of the tongue adjacent the electro-tactile element. A wireless receiver coupled to the body may be configured to receive stimulation information wirelessly from outside the mouth of the user. At least one processing unit coupled to the body may be configured to transform the received stimulation information into a stimulation signal for each of the electro-tactile elements, and to provide the stimulation signals to the electro-tactile elements.
Abstract:
Example devices and methods of tongue stimulation for communication of information to a user are disclosed herein. In an example, a tongue stimulation device may include a body configured to be placed entirely within a mouth of the user and atop the tongue of the user. An array of electro-tactile elements may be distributed on the body, wherein each of the electro-tactile elements is configured to stimulate an area of the tongue adjacent the electro-tactile element. A wireless receiver coupled to the body may be configured to receive stimulation information wirelessly from outside the mouth of the user. At least one processing unit coupled to the body may be configured to transform the received stimulation information into a stimulation signal for each of the electro-tactile elements, and to provide the stimulation signals to the electro-tactile elements.
Abstract:
A filament assembly can include: a button having a planar emitter region with one or more apertures extending from an emission surface of the planar emitter region to an internal surface opposite of the emission surface; an inlet electrical lead coupled to the button at a first side; an outlet electrical lead coupled to the button at a second side opposite of the first side; and a low work function object positioned adjacent to the internal surface of the planar emitter region and retained to the button. The planar emitter region can include a plurality of apertures. The low work function object can include a porous ceramic material having the barium, and may have a polished external surface. An electron gun can include the filament assembly. An additive manufacturing system can include the electron gun having the filament assembly.
Abstract:
The use of the electride form of 12CaO-7Al2O3, or C12A7, as a low work function electron emitter in a hollow cathode discharge apparatus is described. No heater is required to initiate operation of the present cathode, as is necessary for traditional hollow cathode devices. Because C12A7 has a fully oxidized lattice structure, exposure to oxygen does not degrade the electride. The electride was surrounded by a graphite liner since it was found that the C12A7 electride converts to it's eutectic (CA+C3A) form when heated (through natural hollow cathode operation) in a metal tube.