Abstract: A disk drive in which the base and the cover are interconnected in spaced positions to provide a marginal, peripheral gap between confronting or adjacent faces or edges thereof. The gap is bridged, closed and sealed by means of a pressure sensitive adhesive tape, a viscoelastic tape, which is energy adsorbing to damp disk drive vibrations.

Abstract: A disk drive in which the rotatable magnetic memory disks and the metal actuator are electrically isolated from the metallic mainframe of the disk drive and the magnetic heads on the metallic actuator, the coils of the magnetic heads and the magnetic memory disks are maintained at electrical potential levels which are sufficiently close to prevent arcing therebetween and which is different from the potential of the main frame. Electrical isolation is achieved by electrically insulating the disk spindle on which the disks are journaled from the mainframe and by electrically insulating the metal actuator from the metal actuator support when the metal actuator support is attached directly to the main frame, or by electrically insulating the metal actuator support from the main frame. An electrical potential is applied to the disks via the disk spindle and to the body of the magnetic heads via the metal actuator arm to provide potential levels which among these parts are sufficiently close to prevent arcing.

Abstract: An actuator structure in which the arms which support the magnetic heads are of sheet material in back-to-back pairs having ends fitted into and clamped between the confronting faces of pads arranged in columns on an actuator body. The pads in each column are cantilevered from the body on deflectable supports, except for one rigid support substantially centrally positioned in each column. A bolt extending through axially aligned holes in the pads and the arms in each column applies pressure to deflect the pad supports and clamp the arms between the pads.

Abstract: Magnetic head signal slimming is achieved using a differential, low order, lumped element, LC ladder network, having a single adjustment, differential feed forward equalization circuit, to provide pulse slimming and a variable, peaked amplitude response without varying the delay (phase) response of the network. The feed forward adjustment is easily varied by selection of the control signal input thereto so that the network gain and the slimming or pulse narrowing of the network is tailored for the difference in pulse widths produced by magnetic heads, which vary over the surface of the magnetic media and which vary from one magnetic head to another.

Abstract: A signal processing system that has an improved modular architecture so that a selected number of arithmetic element (AE) units may be utilized with a single arithmetic element controller (AEC) unit to provide a system that can be readily expanded or decreased on computational ability. All of the AE units perform similar calculations under control of the AEC unit in response to common address control and coefficient signals. Each AE unit has its own extended work store (EWS) unit with all of the EWS units responding to the same address and control signals, from either the AEC unit or an external interface unit to conform to the modular architecture. Each EWS unit is synchronized with the AE unit, thus allowing continuous and high speed computations to be performed. Also, each of the EWS units is coupled to the external interface unit for receiving and transferring data when not being accessed by the AEC unit.

Abstract: An apparatus for launching a payload, such as a spacecraft or satellite, from a launch vehicle in which a single instrumentality is employed to simultaneously impart angular momentum about the center of mass of the payload and linear momentum in a direction along the axis of rotation.

Abstract: A method of providing access to a multiplexed data bus having a plurality of data processing units coupled thereto. Each unit self-assigns sequence numbers thereto for identification purposes. The unit having the lowest sequence number obtains immediate access to the bus and may relinquish the bus by transmitting a control word, or token, with an incremented sequence number. All units receive the token but only the unit having the incremented sequence number gains access to the bus. The token passing continues through the series of sequence numbers and then recycles when no unit accepts the token (bus timeout). A newly added unit self-assigns a sequence number equal to the one transmitted prior to the bus timeout and thus acquires bus access on the next cycle. If a unit in the cycle fails, a bus timeout occurs mid-cycle and the access loop recycles. The units not gaining access to the bus during the cycle decrement their sequence numbers to close the gap, and hence gain access on the next cycle.

Abstract: A method for changing the spin rate of a spinning spacecraft having a dynamic balancing mechanism which utilizes the communications channel between the spacecraft and the receiving terminal, the master index pulse generator on the spacecraft, and the spacecraft axial thrusters. To change the spin rate, a dynamic imbalance of a known wobble angle and phase is introduced by the dynamic balancing mechanism. An axial thruster is then fired for a predetermined time interval thereby coupling a portion of the axial thrust force into the rotational energy of the spinning body.

Abstract: There is disclosed a fiber optic waveguide which is particularly suited for infrared radiation transmission at extended wavelengths. The core of the waveguide is fabricated from heavy ionic compounds selected from metal halides in order to achieve such extended infrared transparency. While it is impossible to prepare these materials into optical fibers using conventional fiber drawing techniques, the present invention teaches how such materials may be prepared into optical fibers using an extrusion process at elevated temperatures and high pressures.

Abstract: A method and associated means for producing simultaneous electrical representations of the electrical and acoustical (heart sound) activity of the heart, in which a pickup device and associated circuits produce a full wave rectified symmetrical heart sound signal annotated by pulses developed from the QRS wave of the electrocardiogram signal.The pickup device is designed to permit the direct (unbuffered) application of the pickup electrodes to the skin of the body and to provide a control of the associated circuits when not in contact with the body to shorten response times when the pickup device is placed in contact with the body.

Abstract: An antenna pointing control system primarily useful for aiming and controlling a communications satellite directional antenna. The invention makes use of a ground based pilot station which transmits an up-link signal to the satellite, including frequency differentiated communication signals and command and control signals. The command and control signals are referred to as the beacon or pilot signal. The pilot signal is a triangular frequency modulation waveform. The communications signals and the pilot signal are received by a common directional antenna on the satellite. A microwave network coupled to a multiple feed horn assembly of the antenna and responsive to the pilot signal produces pilot signal components including a sum signal and east-west and north-south error signals indicative of the corresponding angular errors between the desired antenna pointing direction and the direction from the satellite to the pilot station.

Abstract: A satellite squadron or cluster formation is disposed in a predetermined location in the geostationary orbit, including a plurality of controllably maneuverable communication satellites and a centrally located switching and control satellite. The satellites comprise a simulated geostationary communications platform made up of discrete modules which are not physically attached together. The satellites are grouped together in assigned positions in a relatively close formation, and are provided with cross-link intersatellite radio communications. The switching and control satellite detects the relative position of the communication satellites and sends control signals to maintain them in their assigned positions in the formation. Communication signals are relayed from one place on the earth to another via the satellite cluster formation by utilizing the control satellite as a switching satellite.

Abstract: A stethoscope transducer applicable as a conventional audio transducer and as a phonocardiogram transducer has a body which on one side mounts an electrode carrying chest bell and which on an opposite side mounts a conventional chest bell. A microphone and a rotor assembly are mounted in a cavity in the body. The microphone and earpiece connections on the body communicate through passages in the rotor assembly with the electrode carrying chest bell when the rotor assembly is in a first position and with the conventional chest bell when the rotor assembly is rotated to a second position. These are three electrodes, two being pickup electrodes which each occupy one quadrant of the chest bell rim in diametrically opposite positions. The third electrode is on the rim intermediate the pickup electrodes. The rim is of a non-wettable material providing a hydrophobic surface.

Abstract: A payload such as a spacecraft is deployed from launch vehicle with linear and angular velocity, using a structural arrangement for applying a tangential, single point ejection force to the spacecraft, in which, the single point ejection force and the spacecraft/launch vehicle reaction points enclose the spacecraft center of mass and center of percussion.

Abstract: Arrangements and methods are described employing input optical intensity to output spatial position mapping, for performing optical computing or logic processing functions. An electro-optical device which receives discrete input optical object beams of different intensity levels and a separate readout optical beam, diffracts portions of the readout optical beam to unique spatial positions in two dimensional space, each portion as a function of the intensity of individual discrete input beams or of combinations of the intensities of the input beams. A spatial filter having discrete apertures at selected ones of the unique spatial positions transmits the selected diffracted optical outputs for implementing logic or computing functions.