Abstract: A magnetodistortive actuator includes an elongated active component of a magnetodistortive material mounted on a support and having a stationary and a movable end portion. At least one permanent magnet applied a permanent magnetic bias to the active component to bring it to a desired point of its stress/field characteristic line. The strength of that portion of the magnetic field of the permanent magnet that acts on the active component is selectively varied by changing the magnetic reluctance of a body that is accommodated in a space interposed between the permanent magnet and the active component. The active component is further subjected to a variable magnetic field generated by a solenoid surrounding the active component, so that the active component is selectively shortened and lengthened around its length corresponding to the desired point, with attendant movement of the movable end portion relative to the support.

Abstract: An arrangement for controlledly removing material from an effective surface of a workpiece includes a mounting member which is mounted on a support for movement relative thereto at least in and opposite to a predetermined direction toward and away from the effective surface and a working member which is caused to rotate relative to the mounting member about a rotational axis that extends substantially normal to the predetermined direction. A pressing force acting in the predetermined direction is applied to the mounting member so that successive regions of an outer circumferential surface of the working member which is centered on the rotational axis act on a predetermined zone of the effective surface of the workpiece during the rotation of the working member with local pressures dependent on the magnitude of the pressing force and sufficient to remove material from the workpiece.

Abstract: An arrangement for solder-coating respective end portions of elongated components in a molten solder bath includes a fixture to be loaded with the components. This fixture includes at least one supporting wall that is capable of maintaining the fixture afloat in a predetermined position on an upper surface of the molten solder bath even when the fixture is fully loaded. The supporting wall has at least one opening through which one of the end portions of a respective component passes into the molten solder bath to a depth necessary for the molten solder to coat the respective end portion to the desired extent when the fixture floats in its predetermined position on the molten solder bath.

Abstract: An optical component having a plurality of cooling channels in a surface region underlying its effective surface is manufactured by first forming a precursor of the optical component consisting of a main body which carries the effective surface, and a plurality of solid fugitive material cores embedded in the main body at the desired locations of the cooling channels, and then converting the precursor into at least a portion of the optical component by consolidating the main body, and removing the cores from the cooling channels, such as by melting the fugitive material of the cores.

Abstract: An arrangement for sensing changes in a monitored parameter includes an optical fiber which has at least one sensing fiber length including a sensing portion situated at a monitoring location of a body. Two periodic gratings of the same periodicity are situated in the fiber each at a different end of the sensing fiber length. Such gratings are reflective to a predominant portion of any light that propagates in the fiber and has a wavelength in a stopband range around twice the periodicity.

Abstract: An arrangement for chopping a collimated beam of light traveling in an initial path, includes a flexible mirror which reflects substantially all of the light from the initial path into an auxiliary path in a first configuration thereof. The flexible mirror is deformed by a magnetodistortive actuator from its first configuration to a second configuration in which it disperses the light reaching it in such a manner that all but a minute fraction of the dispersed light propagates outside the path. Further propagation of the light that is reflected by the flexible mirror to the outside of the auxiliary path along the auxiliary path is blocked by an aperture plate having an apeture through which all of the light reflected by the flexible mirror passes when the flexible mirror has its first configuration.

Abstract: A composite structure including fibers embedded in a silica glass matrix is made by first forming a precursor of the structure by embedding the fibers in a matrix of a silica-based glass material which further includes a glass-forming additive that lowers the working temperature range of the material below that of pure silica glass, and by leaching the additive out of the glass matrix material. The thus obtained porous glass matrix may then be consoidated at an elevated temperature that is considerably lower than that which would be needed for manufacturing the glass matrix directly from a material having substantially the same composition as the material of the leached-out glass matrix.

Abstract: An arrangement for detecting metallic particles carried by a fluid includes a metallic probe member which surrounds an elongated passage through which the fluid flows and which is constituted by a split tube having two marginal portions delimiting a gap which extends along said passage and completely separates the marginal portions from one another. Capacitors are arranged at the gap and alternating electric current is caused to flow in the probe member around the passage so that the probe member and the capacitors form a tank circuit having resonance characteristics that are influenced by any inclusion then present in the passage in a manner dependent on the electromagnetic properties of the inclusion. The character of any metallic particle then present in the passage is determined from variations in the alternating electric current that reflect the influence of such metallic particle on the resonance characteristics.

Abstract: A control arrangement for use in conjunction with a flight control computer operating in response to various input signals including those received from a collective stick to control the flight regime of a helicopter, which is operative for causing the helicopter to perform bob-up and bob-down maneuvers, includes a circuitry which generates a first control signal when the helicopter is to perform a bob-up maneuver from its instantaneous altitude to a higher altitude, stores data descriptive of at least one instantaneous altitude at the time of commencement of the first control signal; issues in response to the first control signal, an ascent command signal representative of a helicopter ascent at a maximum permissible ascent rate; generates a second control signal when the helicopter is to perform a bob-down maneuver from the higher altitude to that stored in the storing means; issues, in response to the second control signal, a descent command signal representative of a helicopter descent at a maximum permis

Abstract: An arrangement for testing a concave reflecting surface of a solid body, especially a relatively complex concave reflecting surface such as that of an X-ray barrel optics mirror element, for deviations of its actual shape from its ideal shape includes a laser source and a negative cylindrical lens interposed between the laser source and the reflecting surface to be tested. The lens optically modifies the laser beam in such a manner as to propagate between the lens and the reflecting surface substantially normal to the reflecting surface and to be reflected from the latter for propagation back to and through the lens toward the laser source as a return laser beam having a wave front indicative of the actual shape of the reflecting surface and any aberrations of the lens. The arrangement further includes an interferometer that forms an interference pattern between the original and return laser beams, and a circuitry for evaluating the interference pattern.

Abstract: An arrangement for smoothing a coherent laser beam of a limited yet substantial coherence length due to the presence of several discrete optical frequencies therein is operative for subdividing the coherent laser beam into a plurality of partial beams of substantially the same intensity. Each of the partial beams is then conducted in a different path, the length of at least one of which differs from that of another path by a distance amounting to a fraction of the coherence length. At least some of the partial beams are subsequently combined into a coherent output beam in which the partial beam issued from the one path is shifted by the distance relative to that issued from the other path.

Abstract: An arrangement for controlling the vibratory behavior of an integral structural component includes at least one element of memory metal material two portions of which that are spaced by a predetermined distance from one another in a first state of the memory metal material are connected while the memory metal material is in its first state to respective locations of the integral structural component that are spaced substantially by the predetermined distance from each other along a region of the integral structural component which undergoes considerable cyclical dimensional changes while the integral structural component vibrates.

Abstract: A scroll compressor includes a fixed scroll element stationarily mounted on a support and an orbiting scroll element which is caused by an eccentric crank portion of a drive shaft to conduct an orbiting motion relative to the fixed scroll element. The drive shaft is rotatably mounted on the support by respective support bearings and carries a plurality of counterweights which have such respective masses and angular distributions about the shaft that the loadings of the support bearings by the drive shaft during the operation of the scroll compressor are minimized.

Abstract: The movement of a predetermined zone of a surface of a vibrating object is measured by separating a laser beam having a predetermined coherence length into a probe beam and a reference beam. The reference beam is then delayed relative to the probe beam by a predetermined time interval sufficient for the probe beam to travel through a predetermined distance at least corresponding to the coherence length, before being combined with the probe beam to form a combination beam. The combination beam is then subdivided into a plurality of substantially equal component beams each of which is conducted along a separate path to a location spaced from the predetermined zone substantially by one-half of the distance traveled by light in the predetermined time interval between the above location and the predetermined zone.

Abstract: A method of manufacturing surface acoustic wave devices includes providing a dielectric substrate with a plurality of channels which open onto a substrate surface region and each of which accommodates a metallic electrode, the electrodes being recessed below the substrate surface region by an actual distance which at least equals a desired distance at which the electrodes have a minimum acoustic reflectivity, testing the performance of the device to ascertain at least the acoustic reflectivity of the electrodes, and etching at least the dielectric substrate, when it is ascertained during the testing that the acoustic electrode reflectivity is excessive, at least at the substrate surface region to a predetermined etching depth. The use of this method results in a device having reduced post-etching acoustic electrode reflectivity as a result of the thus obtained reduction in the difference between the actual and desired distances.

Abstract: A CO.sub.2 gas laser is equipped with a gas mixture control arrangement which introduces into the interior of the laser, of the constituent component of water, only hydrogen, in such amounts based on the instantaneous humidity of the gas mixture that the dew point of water vapor resulting from the combination of the thus introduced hydrogen with incidental oxygen present in the laser interior as an incident to the operation of the laser is maintained within a predetermined range.

Abstract: An arrangement for controlling the position of a movable member, especially an aircraft control surface member, includes an operational amplifier and a capacitor connected in parallel to the amplifier. The control arrangement further includes a detector which detects the restoration of the supply of electric power following its interruption and generates a limited-duration pulse. This pulse is then used to close a switch, which is interposed between an input terminal of the capacitor and the ground, for the duration of this pulse, so that the capacitor is charged much more rapidly than otherwise. The output signal of the combination of the operational amplifier and the capacitor is supplied to an actuator for the movable member so that the extent of excursion of the movable member out of its desired position after the electric power supply has been restored is minimized.

Abstract: A magnetodistortive acutator arrangement for a flexible mirror that is mounted on a support includes an array of magnetodistortive actuators. Each of these actuators includes an elongated core of a highly magnetically permeable material stationarily mounted on the support, centered on a longitudinal axis and having two axially spaced end portions, a solenoid coil surrounding one of the end portions of the core and operative when energized for generating an electromagnetic field which permeates the core and has a high intensity region extending beyond the other of the end portions of the core, an active member of a magnetodistortive material connected to the core and extending axially beyond the other end portion thereof at least partially through the high-intensity region of the electromagnetic field for the latter to cause a change at least the axial dimension of the active member, and a transmitting member which applies this change to the flexible mirror.

Abstract: A mirror arrangement includes a flexible faceplate having a reflective surface and a flexible backing plate which are so mounted on a support that the backing plate is situated behind the faceplate with a gap in between. An array of elongated actuators is arranged on the support rearwardly of and perpendicularly to the backing plate. Each actuator includes an actuating member which is movable in the longitudinal direction of the actuator and exerts a selected force on the backing member at least when the respective actuator is energized. This force is transmitted to the faceplate through respective actuator posts. The gap is sealed with respect to the exterior of the mirror arrangement to form an enclosed cooling chamber.

Abstract: A power distribution system includes a plurality of power sources and load transfer units including transistors and diodes connected in series and leading to a common power output, each of the transistors being controller switchable subject to voltage levels of the respective input and output sides of said transistors, and the voltage and current level of said common power output. The system is part of an interconnection scheme in which all but one of the power sources is connected to a single load transfer unit, enabling the survival of at least a single power source with the failure of one of the load transfer units.