A shaft lock for interconnection of an elongate tubular lacrosse handle and a plastic lacrosse head. In a first embodiment, the shaft lock comprises an elastomeric insert compression-fitted inside the handle. The insert has a compressible body portion which, in an uncompressed form generally conforms to the interior walls of the handle and is defined by a plurality of co-planar ribs that span the interior walls of the handle and a hard screw-anchor embedded within the elastomer insert. In additional embodiments, the shaft lock comprises a collared male plug removably or integrally formed within said lacrosse head for joining said head to a hollow lacrosse handle. The collar surrounds the core plug such that a gap exists between the core plug and the collar for receiving the wall of said handle. The core plug may comprise four or more rotationally-symmetric ribs to correspond to one or more interior shapes of said handle. Said ribs may be formed in whole or in part of a resilient elastomeric material for compression fit of the handle between the plug and the collar of the shaft lock. The plug may be further anchored inside said handle by at least one screw threaded through the handle into the core plug. This avoids loosening and/or dislodgement as a result of impact or vibration, and resists the threads of the screw from stripping either the handle wall(s) or the insert as a result of torque or other stress,

Flexure structures, assemblies incorporating flexure structures, and methods utilizing flexure structures to support objects are provided. A flexure structure as disclosed can be formed monolithically from a single piece of material, includes a center aperture to accommodate at least portions of other elements or structures, allows for rotation of a supported object in two axes with very little translational movement of the supported object, provides mounting fixtures on opposite sides of the flexure structure, and has a relatively high load capacity. Flexure structures include base mounts that can each be joined to a first side of an interconnect structure by flexure blades, and object mounts that are each joined to a second side of the interconnect structure by flexure blades. The flexure structure can be a generally annular structure, with the center aperture formed or defined at least in part by the interconnect structure.

A twistable and stackable shelf includes storage members, an elastic member, a first supporting pipe, a second supporting pipe, a first connecting member, and a second connecting member. Each of the first and second connecting member includes an end portion defining an inserting hole and an inserting portion defining a bottom groove and fluidly connected to the inserting hole. Two ends of the elastic member are inserted into the inserting holes and extend to the bottom grooves; two hooking members are arranged in the bottom grooves. The first and second supporting pipes form a vertical arrangement through the first and second connecting members and support the plurality of the storage members in a vertical direction. Or, the first and second supporting pipes form a horizontal arrangement through the first and second connecting members, and the storage members are twisted and stacked in the vertical direction.

A flexure assembly includes a first spiral flexure, a second spiral flexure, and a spacing element. The spacing element is positioned between the first spiral flexure and the second spiral flexure. The flexure assembly also includes a plurality of fasteners that collectively extend circumferentially around an axis defined by the flexure assembly. Each of the plurality of fasteners extends through the first spiral flexure and the second spiral flexure.

A multitude of flexure mechanism designs are set forth herein that furnish enhanced stiffness properties. The flexure mechanism designs can have various stages including ground stages, motion stages, flexure stages, and reinforcement stages, among other possible stages depending on the construction of the flexure mechanism designs. It has been determined that stages constituting twin stages can be connected via one or more inter-stage connections.

A multitude of flexure mechanism designs are set forth herein that furnish enhanced stiffness properties. The flexure mechanism designs can have various stages including ground stages, motion stages, flexure stages, and reinforcement stages, among other possible stages depending on the construction of the flexure mechanism designs. It has been determined that stages constituting sister stages can be connected via one or more in-plane inter-stage connections.

A bed comprises a fixed width deck section, a wing movably coupled to the fixed width section, and a mechanism for extending and retracting the wing.

A multitude of flexure mechanism designs are set forth herein that furnish enhanced stiffness properties. The flexure mechanism designs can have various stages including ground stages, motion stages, flexure stages, and reinforcement stages, among other possible stages depending on the construction of the flexure mechanism designs. It has been determined that stages constituting sister stages can be connected via one or more in-plane inter-stage connections.

A bed comprises a fixed width deck section, a wing movably coupled to the fixed width section, and a mechanism for extending and retracting the wing.