Abstract: Method and apparatus are provided for reducing vibration in bearings. There are provided first and second bearing rings with races, rotating members rollingly engaging both first and second bearing races, a cage for aligning the rotating members between the first and second bearing races, and vibration reduction means coupled to the cage. The vibration reduction means preferably comprises one or more resonant spring-mass combinations mounted in or on the cage. Damping means is preferably included with the resonant spring-mass combinations. The resonant frequencies of the unmodified bearing cage are first determined and then the spring-mass combinations tuned so that the spring-mass combinations when attached to the cage absorb vibrational energy that would otherwise excite cage vibrations. By selecting the type of spring-mass combination different vibrational modes can be suppressed and/or controlled.

Abstract: A control system is provided for controlling the shape of a flexible electromagnetic radiation structure. The control system includes a plurality of actuators and a plurality of computational elements. Each of the plurality of actuators is coupled to a portion of the radiation structure and can be selectively actuated by the plurality of computational elements. Thus, the plurality of actuators and the plurality of computational elements provide control of the flexible electromagnetic radiation structure shape. In one embodiment, each of the plurality of computational elements controls one section of the flexible electromagnetic radiation structure. Thus each of the plurality of computational elements receives controls the one or more of the plurality of actuator within its section. Together, the plurality of computational elements provide a distributed control network for the radiation structure.

Abstract: A control system is provided for controlling the shape of a flexible electromagnetic radiation structure. The control system includes a plurality of actuators and a plurality of computational elements. Each of the plurality of actuators is coupled to a portion of the radiation structure and can be selectively actuated by the plurality of computational elements. Thus, the plurality of actuators and the plurality of computational elements provide control of the flexible electromagnetic radiation structure shape. In one embodiment, each of the plurality of computational elements controls one section of the flexible electromagnetic radiation structure. Thus each of the plurality of computational elements receives controls the one or more of the plurality of actuator within its section. Together, the plurality of computational elements provide a distributed control network for the radiation structure.

Abstract: An inertial control and measurement system is provided for applying inertial control to a vehicle and measuring angular rate of the vehicle. The system includes a control moment gyroscope having a spinning rotor, a gimbal, a gimbal support assembly attached to a spacecraft for allowing rotation of the gimbal about a gimbal axis, and a gimbal motor for rotating the gimbal about the gimbal axis to induce torque. A controller controls the gimbal motor to generate a control torque. The controller further determines an angular rate of the vehicle as a function of a determined torque and a gimbal angle acceleration.

Abstract: An inertial control and measurement system is provided for applying inertial control to a vehicle and measuring angular rate of the vehicle. The system includes a control moment gyroscope having a spinning rotor, a gimbal, a gimbal support assembly attached to a spacecraft for allowing rotation of the gimbal about a gimbal axis, and a gimbal motor for rotating the gimbal about the gimbal axis to induce torque. A controller controls the gimbal motor to generate a control torque. The controller further determines an angular rate of the vehicle as a function of a determined torque and a gimbal angle acceleration.

Abstract: A constant volume damper which has a very constant damping constant over a considerable range of frequencies by including check valves that prevent cavitation as a piston moves in a chamber. The damper is also sealed for use in space application and is temperature compensated.

Abstract: A moment control device for positioning a spacecraft which employs a plurality of spinning bodies operable to impart a desired torque to a space craft, the bodies being constructed in a unitary combination and the unitary combination being mounted to the spacecraft to be positioned.

Abstract: A vibration isolator which uses a compressible fluid such as air within a pair of flexible chambers interconnected by a restrictive passage, with one of the chambers connected between a first member which may vibrate and a second member which is to be isolated from vibration so that with vibration of the first member, the compressible fluid is compressed and expanded to force compressible fluid to flow through the restrictive passage between the first and second flexible chambers, and provide desired damping of vibration to the second member.

Abstract: A tuned mass damper using a single predetermined mass connected to springs of predetermined stiffness along each of at least two directions to absorb energy from a vibrating structure to which it is attached and damp the vibrations in a rapid and efficient manner with a minimum of weight and volume used.

Abstract: A vibration isolation apparatus having a shaft with an axis therethrough. The shaft has a first and second end. A piston having an axial bore is coaxially positioned with the shaft to provide a damper by forming a damping path between the piston and the shaft. A flange extends radially from the piston for coupling the apparatus to a load. A first extension is coupled to and extends radially from the first end of the shaft and a second extension is coupled to and extends radially from the second end of the shaft. Secondary bellows extending from and secondary fluid paths extending through the first and second extensions provide a first volumetric stiffness in series with the damper. Primary bellows connect the flange to the first and second extensions and are coaxial with the shaft to provide a second volumetric stiffness parallel with the damper and the first volumetric stiffness.

Abstract: A damping apparatus including a piston having an axis therethrough. The piston includes a coaxial body portion and a first and second end extending oppositely therefrom along the axis. A rigid housing is coaxial with and surrounds the body of the piston for forming a rigid fluid volume between the piston and the rigid housing. The rigid fluid volume includes a first fluid chamber at a first end of the piston and a second fluid chamber at the second end of the piston. The first and second fluid chambers are connected by a damping path. The damping apparatus further includes a flexible housing coupled to the first and second ends of the piston and surrounding the rigid housing to form a fluid return of lower resistance to flow than the damping path between the rigid housing and the flexible housing and to allow movement of the rigid housing with respect to the piston.

Abstract: A system for isolating a supported structure from transmitting vibrations to a supporting base in a spacecraft provides six degrees of freedom in a kinematic mounting. Six isolator elements in a symmetric arrangement of three skewed isolator pairs provides viscous damping and vibration and shock attenuation during launch and operation in space. The isolators employ two degrees of freedom flexure joints at each mounting point to assure primarily axial deflection and minimize bending moments, and have tuning springs to optimize performance. The system permits deterministic design and allows calculation of all loads from the nominal geometry and the isolator axial stiffness. Limit stops are provided between the supporting structure and the supported structure to limit excursions of the isolator members.

Abstract: A vibration absorbing damper of the viscous type having an outer cylinder enclosing a damping member with the damping member positioned for axial movement within the outer cylinder while retaining a hermetic seal without the use of gaskets or seals. The damping member is comprised of a pair of arcuate structures with high volumetric rigidity and joined axially by a nonelastomeric member. A fluid-retaining reservoir is deformed by forces applied to the exterior cylinder, resulting in deformation of the arcuate structure and resulting compression or extension of the fluid reservoir. Excess fluid is forced into a bellows through a restricting orifice for storage during compression stresses, and returned from the bellows to the fluid reservoir during extension of the outer cylinder during cyclical vibration. The damper operates with deflections as small as 1 microinch and provides a large actuating force, even though the motion is very small.

Abstract: A viscous damper for absorbing vibrations of low amplitude over a wide frequency range. Two working volumes of resiliently deformable material, in the form of a bellows, are provided in a folded structure joined by a base carrying a restrictive annular fluid passage. Compressive forces applied to the primary volume are transmitted by a damping fluid through the restrictive annulus to the secondary volume, the resulting energy dissipation providing a damping effect. A hermetically sealed configuration provides multi-axis damping and isolation without wearing of frictional surfaces. Large damping values are attained with linear performance over a large dynamic range.

Abstract: A vibration damping and isolation apparatus wherein in damping is obtained by purely viscous fluid shear forces. The fluid is sealed in two chambers divided by a orifice to permit fluid flow. Chamber containment of the fluid and chamber volume change is provided by metal bellows which are arranged to provide a constant overall volume. Coulomb forces are avoided by the elimination of rubbing surfaces.

Abstract: A floating bearing having a stationary member and an axially translating member including a pair of O-rings which in combination with surfaces of the movable member and the stationary member define a contained space which is further subdivided by an extension of a surface of either the translating member or the stationary member to form two chambers substantially enclosed but connected through a restricted space formed by the extremity of the extension and a proximate opposing surface of the other member. The chambers are substantially filled with a viscous fluid which provides damping of axial displacements of said movable member relative to said stationary member produced in vibratory environments.