Abstract: A reticle design is disclosed for use in the first focal plane, which can be used both for close range and long range shooting. A phosphor luminescent material or other type of visible reflecting material is used with a diffraction pattern to enhance the brightness or visibility of all or a portion of the reticle, and may be used alone or in connection with other ways of illuminating the reticle.

Abstract: Rifle scopes with adjustment stops include a scope body, a movable optical element defining an optical axis enclosed by the scope body, and a turret having a screw operably connected to the optical element for adjusting the optical axis in response to rotation of the screw. The turret has a stop element selectably engaged to the screw. The body defines a stop surface positioned for engagement by the turret stop element to limit rotation of the screw, such that the relative position at which the stop element is secured to the screw defines a zero position of the screw and the movable optical element. The stop element is held against the stop surface by an indexing portion while the relative position at which the stop element is secured to the screw to define the zero position is determined.

Abstract: A dental model articulator of the type that has separable complementary articulation members is connected to a registration object having compatible complementary articulation members. The dental arches of each dental model articulator half is scanned with the reference object to give the axis of the articulator model. This facilitates generating a virtual dental model.

Abstract: A modular wheelchair comprises a number of different modules that include a chassis module with frame members substantially centered along a center plane through the chassis, so that the chassis is able to lay flat when the modules are dissembled. The chassis is connected to a drive module by a single plug/receiver mechanical coupling that may include opposite end geometries. When the plug is in a seated position within the receiver, first end geometries of the two components mate mechanically to resist radial movement, while the second end geometries mate mechanically to resist both radial movement and rotation about an axis of the coupling. Additionally, axial movement in one direction is resisted, with the coupling oriented to apply gravitational force to resist axial movement in the opposite direction. The same arrangement may be used for a seat module.

Abstract: Rifle scopes with adjustment stops include a scope body, a movable optical element defining an optical axis enclosed by the scope body, and a turret having a screw operably connected to the optical element for adjusting the optical axis in response to rotation of the screw. The turret has a stop element selectably engaged to the screw. The body defines a stop surface positioned for engagement by the turret stop element to limit rotation of the screw, such that the relative position at which the stop element is secured to the screw defines a zero position of the screw and the movable optical element. The stop element is held against the stop surface by an indexing portion while the relative position at which the stop element is secured to the screw to define the zero position is determined.

Abstract: A device for reducing vehicle aerodynamic resistance for vehicles having a generally rectangular body disposed above rear wheels, comprising a plurality of flexible opposing flat sheets and a plurality flexible load bearing struts attached to the bottom of the rectangular body, that bend to resist damage when struck by the ground, and guide airflow around the rear wheels of the vehicle to reduce its aerodynamic resistance when moving.

Abstract: Rifle scopes with adjustment stops include a scope body, a movable optical element defining an optical axis enclosed by the scope body, and a turret having a screw operably connected to the optical element for adjusting the optical axis in response to rotation of the screw. The turret has a stop element selectably engaged to the screw. The body defines a stop surface positioned for engagement by the turret stop element to limit rotation of the screw, such that the relative position at which the stop element is secured to the screw defines a zero position of the screw and the movable optical element. The stop element is held against the stop surface by an indexing portion while the relative position at which the stop element is secured to the screw to define the zero position is determined.

Abstract: A motion control system for lever propulsion of a wheelchair enables a number of different manipulations at the hand grip of the lever. In some embodiments, as many as five user-controlled operations may be performed without need to remove a hand from the hand grip. A user applies force to the hand grip to initiate the motion lever in its forward and rearward strokes. In addition, the hand grip may be pivoted relative to the lever in order to control a brake. A parking brake mechanism may be provided at the hand grip to apply constant brake force. The direction shifter at the top of the hand grip may be used to shift between forward, neutral and rearward modes of operation. In some embodiments, steering of a front caster wheel is possible by rotating the hand grip. Further along the lever, the power applied per lever stroke is adjustable.

Abstract: A monocular with attachment points has a tubular frame with a hard point attached to its exterior an optical axis defined by its center axis. A clip may have one end connected to the hard point. There may be two hard points attached to the frame's exterior, and the clip may be operable to detach from and reattach to either of the hard points. The hard points may be arranged in pairs on opposite sides of the frame's exterior. There may be a hand strap operable to detach from and reattach to any of the pairs of hard points. There may be a mounting surface rigidly connected to the frame's exterior. The mounting surface may be parallel to the optical axis and operable to receive a tripod mount and a picatinny rail mounting plate.

Abstract: An assembly for attachment of a propulsion system to a wheelchair frame includes a clamp which remains fixed to the frame, while an attachment device that enables three dimensions of adjustability permits quick release of a main wheel and the propulsion system (e.g., lever drive, pushrim and motor drive) that propels the main wheel. The clamp includes a first alignment feature, such as a pin. A spring-loaded latch may also be included. The attachment device includes a second alignment feature, such as a hole or slot, configured to mate with the first. To permit alignment for a number of different wheelchair frame geometries, the attachment device is rotatable to provide angular adjustability, structured to permit lengthwise adjustability, and coupled using hardware which provides offset adjustability in a direction generally parallel to the axis of the wheel.

Abstract: Rifle scopes with friction reducing elements include a scope body, a movable optical adjustment element connected to the scope body, and a turret rotatably connected to the scope body. The turret includes a contact element contacting the adjustment element at a location of contact. The contact element is rotatable with respect to the turret. The adjustment element at the location of contact differs in hardness from the hardness of a second portion of the adjustment element. The contact element at the location of contact and the adjustment element at the location of contact are of essentially equal hardness.

Abstract: Rifle scopes with low-light visible elements include a scope body, a movable optical element defining an optical axis enclosed by the scope body, a turret operably connected to the optical element for adjusting the optical axis, and a low-light visible element attached to the turret such that the rotational position of the turret can be determined by viewing the low-light visible element. A tactile indicator may be attached to the turret such that the rotational position of the turret can be determined by touch. A plurality of indicia may be attached to the perimeter of the turret such that the rotational position of the turret can be determined by viewing the indicia. At least one of the indicia may be visible in low-light conditions.

Abstract: A device for reducing vehicle aerodynamic resistance for vehicles having a generally rectangular body disposed above rear wheels, comprising a plurality of flexible opposing flat sheets and a plurality flexible load bearing struts attached to the bottom of the rectangular body, that bend to resist damage when struck by the ground, and guide airflow around the rear wheels of the vehicle to reduce its aerodynamic resistance when moving.

Abstract: A reticle for stadiametric rangefinding has a horizontal crosshair and a vertical crosshair that are attached to an optical element. The optical element defines an optical axis and a field of view. The crosshairs intersect perpendicularly at a location that is offset from the optical axis. There may be a plurality of rangefinding indicia shaped to indicate the size of an object at a specific range. The rangefinding indicia may be arranged in a position other than vertical.

Abstract: A drive mechanism for a lever propulsion wheelchair includes at least one clutch and at least one gear set contained within a central hub housing operatively coupled to the drive surface of the main wheel being driven. In the preferred embodiment, there are additional clutches and gear sets contained within the hub housing and coaxial to the wheel. By locating the transmission components within the hub housing and providing the coaxial arrangement, various user capabilities may be enabled without a significant increase in wheelchair width, as compared to the width of conventional pushrim propulsion wheelchairs. Transmission components are cooperatively arranged to provide capabilities that may include forward, rearward and neutral “gears,” braking, anti-rollback, and quick-release removal.

Abstract: A dental model articulator of the type that has separable complementary articulation members is connected to a registration object having compatible complementary articulation members. The dental arches of each dental model articulator half is scanned with the reference object to give the axis of the articulator model. This facilitates generating a virtual dental model.