Abstract: Vibration absorbers are provided which utilize a torsional spring and a dynamic mass to control vibrations that occur within the structure to which they are attached. Additionally, pipeline systems are provided which utilize such vibration absorbers including a mass and a torsional spring to control the vibrations that occur within the pipeline system. In various embodiments of the present invention, the torsional spring is one or more elastomer elements coupled between the dynamic mass and a support frame to produce a spring force responsive to pivotal rotation of the dynamic mass relative to the support frame. In various embodiments, one or more elastomer elements arranged in series or in parallel may be used as the torsional spring to provide a desired vibratory dampening characteristic for applications, such as pipelines. Use of such torsional springs may provide a more simplified design with less mechanical joints which may be less susceptible to failure in harsh environments.

Abstract: A prosthetic suspension unit for cushioning shocks in amputees is provided. The prosthetic suspension unit has a first member adapted to be secured to a first prosthetic member and a stop located in the first member. An attachment member is adapted to be secured to a second prosthetic member. A bearing member is operative between the attachment member and the first member such that the attachment member may slide freely in an axial direction relative to the first member. An elastomeric energy storage element is positioned within the first member and includes a first portion abutting the stop. A second portion abuts a face axially moveable with the attachment member to compress the storage member upon application of load by the user.

Abstract: A device for absorbing vibration is disclosed, along with compensator elements for use therein. The device comprises a primary fluid system for dynamic isolation and/or damping, and a volume compensator having an auxiliary chamber fluidly interconnected with, but dynamically isolated from, the primary fluid system. The volume compensator features a compensator element having an elastic layer in fluid communication with the auxiliary chamber and disposed in sealing engagement within the device. The compensator element advantageously comprises a deformable elastomer stiffener cooperative with the elastic layer for providing static pressurization to the primary fluid system. The compensator element may further provide a reduced rate of change in volume stiffness characteristic that allows the fluid pressure in the primary fluid system to increase at a reduced rate. Further, the reduced rate characteristic prevents excessive static pressure swings. The compensator element may further comprise a seal bead.

Abstract: A controllable medium device for resisting movement (rotary, linear, or sliding) between two relatively moveable members includes a first member and a second member coupled for relative movement having a working space between them, and a controllable medium retaining structure, for example, an absorbent matrix, to hold a controllable medium only in the working space. A field generating coil is mounted to one of the first and second members to generate a field acting on the first and second members and the controllable medium in the working space. The rheology change in the medium produced by the field results in resistance to relative movement of the first and second members. A device according to the invention may be used in apparatus, such as washing machines, exercise equipment, air supported tables, and a range of other apparatuses that would benefit from controlled damping or braking.

Abstract: A damper (20) for damping motion between two relatively moveable members, such as pivotal motion between components in office chairs (10). The damper (20) includes a outer member (22) having an internal recess (23) with a inner surface (24) and a crosswise oriented hole (30) intersecting the recess (23), and an inner member assembly (32) moveable relative to the outer member (22) having a shaft (34) with a resilient friction member (38) mounted thereon. The resilient friction member (38) frictionally engages the inner surface (24) in an interference fit relationship thereby radially precompressing the resilient friction member (38). The resilient friction member (38) preferably has one or more protrusions (40) that may be axially or radially oriented.

Abstract: In a seat suspension system, a method for adjusting the gain applied to a control signal to accommodate for large variations in rider weight and input severity and thereby provide rider comfort over a wider range of conditions than is possible with fixed gains or tunings. The method of the present invention is adaptable to changes in system operating conditions.

Abstract: A magnetically actuated motion control device includes a housing defining a cavity and including a slot therethrough. A movable member is located within the cavity and is movable relative to the housing. A magnetic field generator located on either the housing or the movable member causes the housing to press against the movable member to develop a friction force.

Abstract: A haptic interface system or force feedback system having a magnetically-controllable device that provides resistance forces opposing movement. The magnetically-controllable device is adapted for use with a force feedback computer system to provide force feedback sensations to the system's operator. The magnetically-controllable device contains a magnetically-controllable medium beneficially providing variable resistance forces in proportion to the strength of an applied magnetic field. The system further comprises a controller that executes an interactive program or event, a video display, and a haptic interface device (e.g. joystick, steering wheel) in operable contact with an operator for controlling inputs and responses to the interactive program.

Abstract: An resilient member for a side bearing assembly includes a first rigid element extending in a linear direction and having a first end and a second end. A second rigid element extends in the linear direction of the first rigid element spaced from the first rigid element to provide a space between the two. The second element also has a first end. The first end of the second element is displaced along the linear direction away from the first end of the first rigid element. Resilient or elastomeric material fills the space between the first rigid element and the second rigid element with a substantially concave profile connecting the first ends of the two elements. The resilient material includes at least one weakened region along the substantially concave portion thereof as a result of assembly, which is located where the resilient material is subjected to the relatively lower stresses and strains when used in a side bearing assembly.

Abstract: A mount for use in the suspension system of a railway that truck limits the relative lateral movement between a side frame member and a bearing adapter. In one embodiment, the mount includes a rigid material layer having at least four sections laterally angled between a horizontal axis and a vertical axis. A first and second elastic material layer are respectively positioned between the side frame member and rigid material layer, and between the rigid material layers and bearing adapter. The first elastic material layer has least four sections abutting and conforming to at least four sections of the rigid material layer. In addition, the second elastic material layer has at least four sections abutting and conforming to at least four sections of the rigid material layer. The angled sections cooperate to increase the lateral spring rate of the mount, and improve the ride characteristics and high speed stability of the railway truck.

Abstract: A controllable damper for resisting movement between two relatively moveable members includes a first member and a second member coupled for relative movement having a working space between them, and a controllable medium retaining structure, for example, an absorbent matrix, to hold a controllable medium in the working space. A field generating coil is mounted to one of the first and second members to generate a field acting on the first and second members and the controllable medium in the working space. The rheology change in the medium produced by the field results in resistance to relative movement of the first and second members. According to a preferred embodiment, transmission is included to convert linear motion of a first component to rotary motion of the second member. The transmission allows amplification of the relative speed between the first and second members.

Abstract: A haptic interface system or force feedback system having a magnetically-controllable device that provides resistance forces opposing movement. The magnetically-controllable device is adapted for use with a force feedback computer system to provide force feedback sensations to the system's operator. The magnetically-controllable device contains a magnetically-controllable medium beneficially providing variable resistance forces in proportion to the strength of an applied magnetic field. The system further comprises a computer system that runs an interactive program or event, a video display display, and a haptic interface device (e.g. joystick, steering wheel) in operable contact with an operator for controlling inputs and responses to the interactive program.

Abstract: A multi-linkage suspension system (20) including isolators (32) positioned at the outboard ends of the linkages (26) for suspending and isolating an engine (22), such as an Auxiliary Power Unit (APU), from a structure (24), such as an aircraft fuselage. The system (20) has a plurality of linkages (26) extending from the engine (22) towards the structure (24); each linkages (26) including an inboard (28) and outboard (30) end, a plurality of outboard isolators (32) attached at the outboard ends (30), a bracket (27) for connecting the outboard isolators (32) to the structure (24), a rod end (34), which is preferably elastomeric and includes an elastomer layer (36), for connecting the plurality of linkages (26) to the engine (22). The system (20) is easily tuned and provides for common components and the location of the isolators (32) minimizes direct exposure to heat and aggressive fluids.

Abstract: An interlock mechanism is provided which includes a controllable fluid within a hydraulic link. The controllable fluid, preferably comprising a magnetorheological fluid, is disposed within the interlock mechanism. The viscosity of the fluid can be changed to allow the interlock mechanism to be actuated. A fluid control means, such as a magnet assembly, is used to control the fluid.

Abstract: An Adaptive Off-state (AO) control method (55) for use in conjunction with a suspension system (10) including a controllable damper (22) interconnecting relatively moveable members (12, 14) to reduce the transmission of vibrational forces therebetween. Such suspension systems (10) are switchable between alternative on- and an off-state in accordance with a primary control method (53) and/or a secondary override control method (59). Sensors (48, 52) monitor the parameters of the suspension system (10), such as the displacement, velocity, and acceleration of the moveable members (12, 14). Damper command signals (107) are provided to the damper (22) in the on-state (116) to adjust the damping characteristics thereof. In the off-state, the damping signal in conventional systems is approximately zero or a constant relatively low magnitude.

Abstract: A controllable pneumatic apparatus including a pneumatic actuator coupled with a linear-acting brake including a field responsive medium. The pneumatic actuator has a housing with a gas cavity, a first piston slidably disposed in the gas cavity subdividing the gas cavity into first and second gas chambers, and an output member coupled to the first piston. The linear-acting controllable brake includes a medium containing cavity subdivided into a first and second chambers, and a second piston rigidly interconnected with, and longitudinally aligned with, the first piston. A passageway interconnects the first and the second chambers and a field responsive medium (e.g., a magnetic fluid) is contained in the passageway. A field generator produces a field to change a rheology of the medium and cause a braking force to be applied to the output member to control motion thereof. A preferable control method implements motion control based upon the kinetic energy and the braking force in the system.

Abstract: A prosthetic insert unit for cushioning shocks in prosthetics is provided. The unit includes attachment member (150 etc.), a lower sleeve (124′ etc), a slide bearing (152′ etc.) to allow free reciprocal motion therebetween, an elastomeric energy storage member (124′ etc.) received in the interior of the sleeve (124′ etc.), a piston (134′ etc.) cooperative with said elastomer member to compress same, and an anti-rotation mechanism. Preferably, the anti-rotation mechanism is integral with the slide bearing (152′ etc.). The elastomer member provides controlled deflection as well as damping for the insert. Preferably, an anti-click element (269 etc.) is provide to minimize rebound clicking. Acoustical elements (268 etc.) may also be included to minimize noise transmission into other areas of the insert.

Abstract: A seismic MR damper for providing controllable damping forces between a first structural member and a second structural member within large structures, such as buildings, bridges, etc.

Abstract: A fluid isolator apparatus (20) for isolating vibration between a vibrating member, such as a helicopter transmission or pylon and another structure, such as a helicopter fuselage. In one aspect, the fluid and elastomer apparatus (20) includes an inner member (24), an outer member (22), and an elastomer element (26) flexibly interconnecting them. First (30) and second (34) operating chambers are interconnected by a passageway (36). Fluid (37) oscillates between the operating chambers (32, 34) through passageway (36). A spring (42) flexibly suspends the piston (40) such that dynamic motion between said inner and outer member (24, 22) displaces piston (40) and spring (42). Preferably the a hollow cavity (28) houses both the piston (40) and a metal coil spring (42). The stiffness of the coil spring (42) may be interchanged to adjust a resonant parameter. Optionally, the piston mass itself or an additional tuning mass (58) mounted on the piston (40) may be used to accomplish tuning.

Abstract: Elastomer dampers (20) and (120) for damping movement between two relatively moveable members, such as shimmy motion between components in an aircraft landing gear assembly (10). Each damper includes a housing (24) having an internal cavity (36) with a cylindrical interior surface (34) and an opening (41), and a member assembly (28, 128) moveable relative to the housing (24) having an elongated shaft (30) received through the opening (41) with a piston head assembly (32) mounted thereon. The piston head assembly (32, 132) has a annular support element (46, 146) received over the shaft (30) with a sleeve-like elastomer member (48, 148) received over it. The elastomer member (48, 148) engages the interior surface (34) in an interference fit relationship thereby radially precompressing the elastomer element (48, 148) in the range of between about 5% and 15%.