Abstract: A shock absorbing assembly (10) has a front plate (12) and a rear plate (14) separated by spacers (16). The plates and the spacers each have holes (18A, 18B), the upper holes (18A) in the front plate preferably being threaded. Fasteners, such as but not limited to threaded rods (22A, 22B) and locknuts (24A, 24B), hold the spacers in position between the front plate and the rear plate. The threaded rods (22A) are screwed into the threaded holes in the front plate but do not protrude from the front face of the front plate. The threaded rods (22A) are secured by locknuts 24A on one end and the threaded rods (22B) are secured by locknuts 24B on both ends. The rear plate also has a pair of engagement plates (20) which position the assembly on the catwalk.

Abstract: Articulating protective systems for resisting mechanical loads and related methods are generally described. The protective structures described herein can incorporate one or more features that enhance the ability of the structure to resist an applied force while remaining sufficiently flexible to allow for movement of the object or person the structure is designed to protect.

Abstract: An active vibration control device is provided that is configured to control the position of a body relative to a reference frame. The control device includes sensors that provide input signals corresponding to movement of the body in at least one direction, a rotary rotary actuator configured to control the position of the body, and four-bar linkage connecting the rotary rotary actuator to the body. The linkage converts the rotary motion output from the rotary actuator into a linear motion of the body. The controller, based on the input signals from the reference frame sensors, provides control signals to the rotary rotary actuator which acts through the linkage to position the body in the at least one direction relative to the position of the reference frame.

Abstract: An aircraft vehicular assembly is provided that includes a nonelastomeric outer tubular member having an inner axial center bore with a tubular cylindrical frictional interface contiguous smooth inner surface segment, and a nonelastomeric inner member having an outer bonding surface segment. The nonelastomeric inner member is rotationally received in the outer member inner axial center bore with the nonelastomeric inner strut member rotatable within said outer member. An elastomer encompasses the nonelastomeric inner strut member outer bonding surface segment. The elastomer has an inner bonding surface segment and an outer grooved elastomer surface, the inner bonding surface segment is bonded to the nonelastomeric inner member outer bonding surface segment.

Abstract: A tuned mass damper comprising a frame, at least one bendable spring element being connected from its ends to the frame, and at least one mass element being connected to the spring element at a distance from the ends of the spring element, at least one movable spring support element for adjusting the tuning frequency of the damper, and means for moving the spring support element.

Abstract: Provided is a vehicle-mounted active vibration reducing device wherein vibrations in a plurality of directions are reduced by a single dynamic damper. Since an actuator is attached so as to be supported by an elastic member attached to a bracket, the actuator can be used as a mass of a dynamic damper. The moving directions of the actuator are the forward and rearward directions, and are different from the moving directions of the dynamic damper using the actuator as a mass, i.e., the upward and downward directions. Accordingly, vibrations can be controlled in the forward and rearward directions which correspond to the moving directions of the actuator as well as the upward and downward directions which correspond to the moving directions of the dynamic damper.

Abstract: Apparatus and methods for controlling drill string vibrations and applying a force to a drill bit include a body having a first piston at an uphole end in association with a drill string and a second piston at a downhole end in association with a drill bit. A first biasing member urges the first piston outward to provide a first force in an uphole direction to the drill string. A second biasing member urges the second piston outward to provide a second force in a downhole direction to the drill bit. When vibration from the drill string compresses the first biasing member, the first force resists the vibration and maintains the apparatus and drill bit in a consistent orientation. When an uphole force from the drill string or the drill bit compresses the second biasing member, the second force prevents movement of the drill bit in an uphole direction.

Abstract: The first corner portion elastically deforms in application of load such that the angle of the first corner portion changes depending on the pressing force from the first member. In this case, the first corner portion can move toward the outside of the inner periphery portion of the main body portion while the angle changes. The second corner portion has the same function as that of the first corner portion, and it can move toward the outside of the outer periphery portion of the main body portion while the angle changes depending on the pressing force from the second member in the elastic deformation of the second corner portion. As a result, the spring can prevent generation of hysteresis in load characteristics without increasing the number of parts, and enables height adjustment of the spring.

Abstract: Systems and methods for providing vibration isolation for a MEMS device are provided. In at least one embodiment, a system comprises a first assembly and a second assembly, wherein the second assembly and the first assembly are joined together, enclosing the MEMS device, wherein the joined first assembly and the second assembly have a recessed groove formed on an interior surface. Further, the system comprises a rigid support encircling the MEMS device, the rigid support fitting within the recessed groove; and at least one mount isolator in contact with a plurality of surfaces of the rigid support, wherein the at least one mount isolator interfaces the plurality of surfaces of the rigid support with the first assembly and the second assembly, when the first assembly and the second assembly are joined together.

Abstract: The invention relates to a support device for the gun sight of a military vehicle, incorporating a head to which the gun sight is fastened and a foot which is integral with the vehicle, the head being integral with a column with a vertical axis which is introduced into the foot, the column being made integral with the foot by spring means wherein the spring means are constituted in the form of tongues arranged along at least two parallel planes perpendicular to the vertical axis of the support, each plane incorporating at least three tongues evenly spaced angularly around the column and integral with it by a first end and integral with the foot by their second end, these spring means imparting stiffness to the link between the column and the foot that is less along the vertical axis than along the other directions (X, Y) orthogonal to this vertical axis.

Abstract: A vibration generating apparatus with high yield, low cost, and can exhibit vibration tactile haptic effects even with variation in the natural frequency of a mechanical vibrator, including a damping system having a damping ratio ?<1 to support a mechanical vibrator to a fastening part, and a magnetizing unit generating a dynamic magnetic field to vibrate the mechanical vibrator by non-contact, the mechanical vibrator generating a beat vibration by making the frequency of a drive voltage applied to the magnetizing unit, from a drive start or middle of drive, to be a non-resonant frequency out of a damped natural frequency of the mechanical vibrator, wherein the apparatus comprises a forced vibration control unit controlling to stop application of the drive voltage, in a beat wave defining an amplitude of the beat vibration, at a second valley part after a first peak part from the side of the drive start.

Abstract: Actuator arrangement with an actuator (8), a reference mass (22), a spring (24) and a first sensor (26; 42, 43; 32, 36). The actuator (8) applies a force between a first object (2) relative to a second object (16; 54). The reference mass (22) is, in use, supported by a third object (16; 56) by means of the spring (24). The first sensor (26; 42, 43; 32, 36) generates a first distance signal that depends on a first distance (z2; z5,z6; z3,z4) between the reference mass (22) and the first object (2) and is provided to a controller (6) to actuate the actuator (8).

Abstract: A vibration damper including a cylinder with a cylinder-side connection member. The at least one mounted component is fastened to the cylinder by a material bond. The cylinder and the mounted component are made of plastic. The mounted component and/or the cylinder are based on at least one ready-prepared semi-finished product that forms the surface of the vibration damper on at least one body side in the final state. Plastic supplemental volume fractions determine the finished body contour.

Abstract: A vibration insulating member is equipped between one component and an other component. The vibration insulating member includes a through hole forming portion and a contact portion. The through hole forming portion is formed of an elastic material to have a through hole in which a connection member is inserted to connect the one component with the other component. The contact portion is projected radially inward from an inner wall of the through hole forming portion. The contact portion has an inner wall on a radially inside. When the connection member is inserted in the through hole, an outer wall of the connection member forms a gap with the inner wall of the through hole forming portion and is in contact with the inner wall of the contact portion.

Abstract: Method and arrangement for oscillation isolation by means of an air bearing. The electropneumatic valves (4) for the compressed-air supply to the air bearing are subjected to a dither signal. This causes additional vibration of the mass 1 to be isolated. A compensation signal transmitter (12) ensures that additional vibration of the mass (1) is suppressed, by controlling actuators (10). Overall, hysteresis effects are avoided in the control of the compressed-air flow.

Abstract: A vehicle seating system includes a top frame for mounting to a vehicle seat. The top frame has integral rails or channels with roller tracks at one end and vibration dampening systems at the other. An opposing pair of the roller tracks includes a vibratory dampening or regulation system that controls the amount of fore and aft travel of the top frame.

Abstract: A vibration isolator having an upper housing defining an upper fluid chamber, a lower housing defining a lower fluid chamber, a piston resiliently disposed within the upper housing and the lower housing, a tuning passage defined by the piston, for providing fluid communication between the upper fluid chamber and the lower fluid chamber, a tuning fluid disposed within the tuning passage, the upper fluid chamber, and the lower fluid chamber. A reservoir in fluid communication with the upper fluid chamber for providing pressurization control of the vibration isolator. An expanded accumulator region for providing Increased pressure retention during maintenance and operation of the vibration isolator.

Abstract: A device for supporting and securing a piece of equipment on an aircraft engine or nacelle case, including a vibration damper including a first part secured to the case and a second coaxial part rigidly connected to the piece of equipment, the damper associated with a safety member configured to hold the damper in place on the case in the event of damper failure or breakage. The safety member, which is independent of the damper, is mounted astride the damper and secured to the case.

Abstract: A shock absorber, for use with headgear having a faceguard, has a sliding member that does not extend beyond the support structure of the shock absorber in a way that would leave it vulnerable to damage. A headgear having a faceguard provides a protected mounting location for mounting a shock absorber for the faceguard.

Abstract: An insulating coating (1) with high damping power and suitable for being fastened to a structure (2). The coating comprises a dissipater mesh made up of a plurality of dissipater elements (3) and of nodes (4) with the bottom end (4?) of each node being fastened to said structure (2). Each dissipater element is secured to first and second nodes (6, 7). The bottom ends (4?) of said nodes (4) project from said dissipater elements (3) so as to be suitable for creating an empty space (5) between the dissipater elements (3) and said structure (2). In addition, at least one dissipater element (3) is provided with at least one branch (10, 20) provided with a heavy element (30, 31, 32). The heavy element (30, 31, 32) has a first mass that is greater than or equal to a second mass of said branch (10, 20).

Abstract: A mounting assembly comprising an inner mounting sleeve having a cylindrical shank, wherein an end of the mounting sleeve is configured to be mounted to a support structure of a motorized device. The assembly comprises an inner grommet having a cylindrical shank, an axial opening of the inner grommet shank configured to accommodate the mounting sleeve shank there-through. The assembly comprises an outer ring sleeve having a cylindrical shank, the outer ring sleeve disposed around a portion of the inner grommet shank, the outer ring sleeve shank configured to accommodate an eyelet of a mounting arm there-around. The assembly comprises an outer grommet having a cylindrical shank, an axial opening of the outer grommet shank configured to accommodate the inner grommet shank there-in.

Abstract: An energy absorbing and transmitting material comprising a framework of interconnected units comprising at least one unit having a base and a protrusion or cone extending from the base along an axis, and at least one connecting member or rod that connects the unit to at least one adjacent unit, the connecting members extending substantially perpendicular to the axis of the unit from the base, where the framework is comprised of a single elastic material throughout, or configured so that when the framework is perturbed by tilting the unit towards the adjacent unit, the adjacent unit is tilted towards the unit.

Abstract: A gas pressure regulator adapted for being mounted to a gas cylinder is provided. The gas pressure regulator includes a body defining a front portion and opposed side portion and a plurality of gas pressure indicators mounted to the front portion of the body. A bonnet is mounted to an exterior portion of the body, and a pressure adjustment knob is mounted to one of the side portions of the body, proximate the bonnet, and horizontally relative to a longitudinal axis of the pressurized gas cylinder. An energy absorbing device is operatively engaged with the pressure adjustment knob and the bonnet, the energy absorbing device being capable of absorbing energy from impact loads imposed on the pressure adjustment knob.

Abstract: A device for stabilizing a launcher, in particular during the firing of camouflage bodies and decoy flares or other systems in which vibrations can build up, thereby subjecting them to shocks. The device is a stabilizer (4) provided on a known damping system (1), for example a metal cable damper etc., into which a re-adjustable system (10), consisting of a rod (11) provided with a curved portion or groove, a pre-loaded device (12), a type of pressure part (13) and a type of pawl part (14), is placed. Pressure can be exerted on the curved portion of the rod (11) by the pre-loaded device (12) using the pressure part (13) and pawl part (14).

Abstract: A displacement amplifier receives an actuation displacement signal from a piezoelectric actuator. The displacement signal is amplified by one or more stages of compliant elements, and a corresponding force is applied to a load. Wide frequency response is achieved in response to the resilience characteristics of the compliant elements that are formed from any of several materials, illustratively aluminum, steel, titanium, plastics, composites, etc., and are produced by any of several manufacturing techniques, illustratively extrusion, die casting, forging, etc. The compliant elements can be configured as plural compliant mechanical displacement amplifier stages. In bilateral arrangements displacement signals from distal ends of the motive source are applied to symmetrical, or mirror image, arrangements of compliant elements. The motive source, which may be a piezoelectric actuator, delivers its displacement signal at one end thereof to one or more compliant elements.

Abstract: A rotor hub and method to dampen a force exerted on a rotor hub by a rotor blade during flight. The rotor hub including a central member rotatably coupled to a rotor mast, a blade grip rigidly attached to a blade and movably coupled to the central member, and an adjustable damper operably associated with the blade grip. The method includes damping the force exerted on the rotor hub with the adjustable damper and selectively adjusting the adjustable damper between a first spring rate and a second spring rate.

Abstract: The invention is a system and method for automatically adjusting the resonance frequency of an energy absorbing device in response to a disruptive force. By configuring an energy absorbing device for automatic response tuning, utilizing a controller coupled to one or more sensors for processing a determination primarily based on sensing data, the natural period of an overall structure may be adjusted (i.e. increased or decreased) so that the acceleration response of the structure is decreased upon being subjected to a disruptive force, for example, high winds, a blast from an explosion, or a seismic force caused by an earthquake.

Abstract: A shock absorber is attached coaxially with a reciprocating rod driven by a reciprocating unit for absorbing an impact force without bending the reciprocating rod. The shock absorber has a hollow rod provided with a through hole. The hollow rod is mounted within an outer cylindrical body. An accommodating space is formed between the hollow rod and the outer cylindrical body. A spring force toward one end portion side of the hollow rod is applied to the outer cylindrical body by a compression coil spring. An annular piston provided in the hollow rod partitions the accommodating space into two liquid chambers. When the impact force is applied to the hollow rod, the liquid flows from one liquid chamber to another liquid chamber through a gap, whereby a resistance force is applied to the hollow rod.

Abstract: An expansion valve includes a vibration-proof spring that develops the sliding resistance by biasing a shaft. The vibration-proof spring includes a base portion constituted by a circular plate having a hole, through which the actuating rod can be inserted, in the central region, a plurality of spring portions, which is installed upright on the base portion and which is so formed as to come in contact with the periphery of the actuating rod, and a plurality of supporting pieces, which extend outward from the base portion and which is formed so that the supporting pieces can be stopped by the body. The supporting piece is structured such that the supporting piece includes a low-rigidity portion whose rigidity is lower than that of the base portion.

Abstract: A power toothbrush having a vibration compensation system, the toothbrush including a toothbrush housing (72), and an actuator which includes a stator (74) having a first moment of inertia and a rotor (76) having a second moment of inertia, at the end of said rotor is mounted a bristle member. A first spring element (86) having a first spring constant connects the stator to the housing, while a second spring element (88) having a second spring constant connects the rotor to the housing, wherein the ratio of the first and second spring constants is substantially the same as the ratio of the first and second moments of inertia.

Abstract: A high-carbon steel wire has as steel composition: a carbon content ranging from 0.40 weight percent to 0.85 weight percent, a silicon content ranging from 1.0 weight percent to 2.0 weight percent, a manganese content ranging from 0.40 weight percent to 1.0 weight percent, and a chromium content ranging from 0.0 weight percent to 1.0 weight percent. The remainder is iron. This steel wire has as metallurgical structure a volume percentage of retained austenite ranging from 4 percent to 20 percent, while the remainder is tempered primary martensite and untempered secondary martensite. The steel wire is obtained by partitioning after quenching.

Abstract: Particular embodiments relate generally to vibration isolation systems and tuned mass dampers. In one embodiment, a vibration isolation system may include a supporting base, an isolated mass, at least one air mount, a control valve, a compressed air supply, and a supervisory controller. The air mount is positioned between the isolated mass and the supporting base. The control valve is pneumatically coupled to the air mount, the compressed air supply and the atmosphere, and is operable to adjust a flow of air to and from the air mount. The supervisory controller receives a mass relative height signal, a mass relative velocity signal, and a mass relative acceleration feedback signal corresponding to a relative acceleration of the isolated mass or a pressure of the air mount.

Abstract: A machine and method to produce structural elements for the building trade made of cement material with one or more inserts made of polymer material. The machine comprises at least a molding member, a loading unit for loading the inserts and a depositing member to deposit the cement material. The molding member is open at the upper part and the loading unit and the depositing member are selectively positionable above the molding member in order to load and deposit from above, respectively, the inserts and the cement material into the molding member, in order to achieve the structural elements.

Abstract: A seismic-incurred-rupture-resistant deformation-recordable buckling-restrained brace is disclosed. A core plate is disposed in the concrete filled steel tubular outer sleeve, and an end portion of the core plate is provided with a core plate stiffening rib. A brace deformation recording device includes two toothed racks, a ratchet gear, a first cord spool, and a second cord spool. The two toothed racks are fixed on the core plate stiffening rib, and ratchet pawls in the length direction thereof face opposite directions. The ratchet gear is fixedly connected to the concrete filled steel tubular outer sleeve. The ratchet gear is disposed between the two toothed racks. A tooth on the ratchet gear is engaged with a ratchet pawl. The first cord spool is fixed on the ratchet gear. The second cord spool is fixed on the core plate stiffening rib.

Abstract: Negative-stiffness-producing mechanisms can be incorporated with structural devices that are used on spacecraft that provide thermal coupling between a vibrating source and a vibration-sensitive object. Negative-stiffness-producing mechanisms can be associated with a flexible conductive link (FCL) or “thermal strap” or “cold strap” to reduce the positive stiffness of the FCL. The negative-stiffness-producing mechanisms can be loaded so as to create negative stiffness that will reduce or negate the natural positive stiffness inherent with the FCL. The FCL will still be able to provide maximum thermal conductance while achieving low or near-zero stiffness to maximize structural decoupling.

Abstract: An assembly for connecting a first body to a second body includes a first element having a connection end to the first body and a first tubular portion, and a second element having a connection end to the second body and a second tubular portion extending along the longitudinal axis. The first tubular portion and the second tubular portion are interlocked by at least one complementary tubular portion nested in the first tubular portion and around the second tubular portion. A rigid piece connects the first body to the second body and is fastened to the first and second bodies. One of the first and second bodies is connected with functional play at one of the two attachment points of the rigid connecting piece, wherein the rigid connecting piece is formed of two flat rigid pieces extending on both sides of the first and second elements along the longitudinal axis.

Abstract: A structural member includes a split beam within a box structure. The split beam may be a segmented beam that includes multiple segments for each of its parts. Movement of the split beam parts within the box structure, as the structural member flexes, dissipates energy and adds to the damping of the structural member.

Abstract: A portable electronic includes a main body defining a plurality of mounting holes at corners; a plurality of mounting modules; a plurality of resilient members compressed and mounted in mounting holes of the main body by the corresponding mounting modules; and a control module. The control module includes a MCU; an acceleration transducer connected to the MCU to sample a real-time acceleration value, and a memory connected to the MCU to store a critical acceleration value. The control module controls the mounting modules to release the compressed resilient members so as to eject out the resilient members from the main body, when the real-time acceleration value is larger than the critical acceleration value.

Abstract: A system and method to control vibrations exerted on a non-vibrating structure. The system includes an adjustable variable stiffness support securely attached to both the non-vibrating structure and a vibrating structure. A driver operably associated with the variable stiffness support is configured to selectively adjust the variable stiffness support. A control system in data communication with both a sensor system and the driver includes an algorithm to determine whether adjustment of the variable stiffness support is required.

Abstract: The present invention is directed to an energy absorption system for absorbing mechanical impact energy using one or more chemicals for promoting absorption of a liquid, and optionally including one or more promoter, recovery agent, and/or viscosity adjusting agent, which allows the system to release the absorbed energy.

Abstract: A multipiece cushioning assembly adapted to be arranged in combination with a shock absorbing apparatus. The multipiece cushioning assembly is disposed between a pair of radial shoulders on first and second members telescoping members of the shock absorbing apparatus arranged in operable combination relative to each other. The radial shoulders on the first and second members limit travel of the shock absorbing apparatus, and with the multipiece cushioning assembly including a plurality of elastomeric bumpers arranged in a generally circular array for absorbing over-travel of the first and second members relative to each other and for readily permitting replacement of the multipiece cushioning assembly while maintaining the first and second members in operable combination relative to each other.

Abstract: The present invention is concerned with a flexing arrangement with a wide range of applications. The arrangement has at least one leaf spring structure having a plurality of reusable leaf springs connected together. At least one of the leaf springs is made of essentially of an alloy of nickel and titanium, and the alloy has a nickel content of substantially 50.1-55 at % and a titanium content of substantially 45-49.9 at %.

Abstract: The present invention provides a panel protecting device of a flat panel electronic device and a flat panel electronic device. The panel protecting device comprises: a sensor for detecting one or more of a falling speed, a falling time and a falling distance of the flat panel electronic device in a vertical direction when the flat panel electronic device is only under gravity; and a protecting means for being mounted around a panel of the flat panel electronic device. The protecting means has a rest position and a protruding position. The protecting means is accommodated in a recess of the flat panel electronic device when the protecting means is in the rest position and protrudes from the panel when the protecting means is in the protruding position. The protecting means moves to the protruding position from the rest position automatically when the one or more of the falling speed, the falling time and the falling distance is greater than or equal to a predetermined value.

Abstract: A dynamic vibration absorber (1) includes: a weight (2); a frame body (3) which surrounds the weight (2); a total of four pairs of vertically mounted U-shaped leaf springs (4, 5, 6 and 7) which are interposed between the frame body (3) and the weight (2) so as to hold the weight (2) with respect to the frame body (3) movably with respect to all directions in a horizontal plane and immovably in a vertical direction (V); and a damping mechanism 8 for damping the vibration of the weight (2) in the horizontal plane.

Abstract: The device of the invention consists in a telescopic element with two arms, one of them movable within the other, having in its corresponding ends attachment means (3), so that the shorter arm (2) has means with an axial groove (5) which in the normal working situation is operatively opposite in respect to an axial chamber (6) of the internal portion of the longer arm (1), so that in said chamber a blocking element is movable vertically in respect to the groove, preferably a cylinder (7) opposing the effort of an elastic element located within the corresponding housing (11) which is encased in said groove (5) blocking the device and permitting its unblocking once the effort of the elastic means on the cylinder is exceeded. The device is reusable and it is easily adjustable to different levels of effort for its unblocking.

Abstract: A device is described for vibration damping, which is attachable on a mechanical structure or integratable therein, having at least one mass which is indirectly or directly operationally linked to the structure via elastic means, referred to as the so-called damper mass, and at least one actuator for changing a stiffness which can be associated with the elastic means. The invention provides an electrical power source, which is capable of generating electrical power exclusively using an oscillating relative movement resulting along the operational link between the damper mass and the structure, and a regulating unit, which is connected to the electrical power source, which activates the at least one actuator as a function of the vibration behavior of the structure based upon a vibration damping rule.

Abstract: A mounting assembly comprising an inner mounting sleeve having a cylindrical shank, wherein an end of the mounting sleeve is configured to be mounted to a support structure of a motorized device. The assembly comprises an inner grommet having a cylindrical shank, an axial opening of the inner grommet shank configured to accommodate the mounting sleeve shank there-through. The assembly comprises an outer ring sleeve having a cylindrical shank, the outer ring sleeve disposed around a portion of the inner grommet shank, the outer ring sleeve shank configured to accommodate an eyelet of a mounting arm there-around. The assembly comprises an outer grommet having a cylindrical shank, an axial opening of the outer grommet shank configured to accommodate the inner grommet shank there-in.

Abstract: Provided is an active noise cancellation apparatus capable of reliably reducing road noise by a technique other than mounting a vibration generator on a floor panel itself or another plate-like interior part itself, while reducing costs and size of the apparatus. A reference signal detector is mounted on a knuckle and the vibration generator is mounted on a wheel housing or a suspension member. An error signal detector detects vibration of the wheel housing or vibration of the suspension member as an error signal, or detects sound in a vehicle interior as an error signal. A controller controls the vibration generator based on the reference signal and the error signal so as to reduce the error signal.

Abstract: A coating method forming a coating film having a predetermined film thickness on a band-like support body. The method includes conveying the band-like support body; forming the coating liquid on the band-like support body using a coating device fixed on an vibration isolation device; and detecting vibration components on a surface of a floor on which the coating device is disposed and controlling vibration of the active vibration isolation device.

Abstract: A shock absorber is provided that also includes vibration damping. The shock absorber includes at least one shock absorbing frame member that partially surrounds an electronic device enclosure. The shock absorber also includes at least two protrusions that protrude from the at least one shock absorbing frame member. Each protrusion extends beyond the at least one shock absorbing frame member from a recessed surface recessed into the at least one shock absorbing frame member.