Abstract: The present disclosure relates to the field of laser display technology and discloses a liquid cooling block, a liquid cooling heat dissipation system and a laser projector. The liquid cooling block includes a housing. A liquid inlet, a liquid outlet and at least two sets of cooling fins are arranged on the housing. At least two liquid storage chambers are formed in the housing. Each of the at least two liquid storage chambers corresponds to one set of the at least two sets of cooling fins. The at least two liquid storage chambers share the liquid inlet and the liquid outlet. One liquid storage chamber and its corresponding cooling fins have a total heat dissipation efficiency different from a total heat dissipation efficiency of another liquid storage chamber and its corresponding cooling fins.

Abstract: A container for a waste heat utilization circuit may include a housing that defines a housing interior such that the housing interior can be flowed through by a working medium. A sheath may be arranged in the housing interior for accommodating an auxiliary medium. The sheath may be fluid-tight and heat-conductive at least in certain areas. The sheath may define a sheath interior of variable volume.

Abstract: A method for semi-continuous operation of a heat exchange process that alternates between two heat exchangers is disclosed. The method comprises, first, providing a contact liquid to a first heat exchanger while the second heat exchanger is on standby. The contact liquid contains a dissolved gas, an entrained gas, or residual small particles that foul the first heat exchanger by condensing or depositing as a foulant onto the first heat exchanger, restricting free flow of the contact liquid. Second, detecting a pressure drop across the first heat exchanger. Third, switching flows of the coolant from the first to the second heat exchanger. Fourth, removing the foulant from the now standby first heat exchanger by providing heat to the heat exchanger, passing a non-reactive gas through the heat exchanger, or a combination thereof. In this manner, the heat exchange process operates semi-continuously.

Abstract: A firearm including a receiver, a barrel, a breech bolt assembly, and a trigger assembly. The bolt assembly has a bolt including a body portion, a lug portion, and a firing pin bore. The lug portion includes outward extending lugs, a cartridge recess, and an off-center hole. The bolt assembly also includes an extractor and an ejector pin. At least some of the lugs on the lug portion of the bolt have a tapering outer face so that a rearward face of the respective lug is taller than a forward face of the respective lug. In another aspect, at least some of the lugs on the lug portion of the bolt have tapering side faces so that a rearward face of the respective lug is wider than a forward face of the respective lug.

Abstract: A bolt assembly is provided for a firearm. The bolt assembly comprises a block adapted to connect to a firearm frame and a bolt carrier adapted to reciprocate within the frame. The bolt assembly comprises a support element between the block and the bolt carrier. The support element is adapted to reciprocate within the frame with respect to the cap and with respect to the bolt carrier. The first and second spaced apart parallel rods are connected to the cap and extending from the cap. The bolt carrier defines a pair of spaced apart bores receiving the rods. A first spring is interposed between the block and the support element, a second spring is received on the first rod, and a third spring is received on the second rod.

Abstract: The light-weight handheld less-lethal ballistic projectile launcher is configured as an “over/under” double barrel handheld device with a “break open” loading action. The launcher includes a barrel section pivotally connected to receiver section. The barrel section pivots between an open load/unload position and a closed firing position. The barrel section includes two metal barrel sleeves that are press fit into axial bores formed in the body of the barrel section. The barrel section also includes an ejector, which locks the barrel section in the closed firing position and partially expels spent rounds from the barrel sleeves when the barrel section is opened. The receiver section houses the launcher's fire control mechanism. The fire control mechanism uses a traditional single action operation and ensures that rounds are alternatively discharged from each barrel and prevents rounds from both barrels from being discharged simultaneously.

Abstract: The light-weight handheld less-lethal ballistic projectile launcher is configured as an “over/under” double barrel handheld device with a “break open” loading action. The launcher includes a barrel section pivotally connected to receiver section. The barrel section pivots between an open load/unload position and a closed firing position. The barrel section includes two metal barrel sleeves that are press fit into axial bores formed in the body of the barrel section. The barrel section also includes an ejector, which locks the barrel section in the closed firing position and partially expels spent rounds from the barrel sleeves when the barrel section is opened. The receiver section houses the launcher's fire control mechanism. The fire control mechanism uses a traditional single action operation and ensures that rounds are alternatively discharged from each barrel and prevents rounds from both barrels from being discharged simultaneously.

Abstract: The invention is a tamper resistant camera positioned on a gun, for example, mounted on the Weaver/Picatinny rail.

Abstract: A firearm is disclosed. The firearm has a power assembly, a member driven by the power assembly between a first position and a second position, and a trigger assembly. The member blocks a movement of the trigger assembly in the first position. The member allows a movement of the trigger assembly in the second position. The member is a rotatable member that rotates between the first position and the second position.

Abstract: A trigger assembly apparatus includes spherical portion(s) and spherical bearing(s), rounded sear, stabilizing catch, and complimentary shield. In an exemplary embodiment, the spherical portion(s) and spherical bearing(s) respond to non-linear movement. Further, the interaction of the spherical portion(s) and spherical bearing(s) results in the mobility of the trigger in relation to the 6 degrees of freedom thereby resulting in the firearm being generally unaffected by side to side movement of the trigger during activation. The trigger assembly may also include but is not limited to a rounded sear, stabilizing catch, and complimentary shield. The rounded portion of the sear engages the hammer stop notch at a single point further resulting in the firearm being generally unaffected by side to side movement of the trigger. Additionally the stabilizing catch and shield helps facilitate the proper reset of the trigger assembly.

Abstract: A bullpup-shaped rifle (“BSR”) or assault rifle (“AR”) able to expel a bullet is disclosed. In some embodiments, the BSR includes a firing control unit (“FCU”), grip module, bullpup rear attachment, and bolt and barrel assembly. The FCU is a serialized trigger mechanism capable of initiating launching a directional object when a trigger of the FCU is pulled. The grip module which contains a grip, FCU housing, and rear stabilizing connector, wherein the FCU housing is configured to house a removable FCU. The bullpup rear attachment which is coupled to the rear stabilizing connector for enhancing stability is configured to have a magazine port for receiving a magazine. The bolt and barrel assembly which is situated above the magazine port inside of the bullpup rear attachment behind the FCU facilitates the firing of the object.

Abstract: A modified assembly configured for firearm capable of propelling ammunition is disclosed. The modified assembly, in some embodiments, includes a firing control unit (“FCU”) and a grip module. The FCU is a serialized trigger mechanism capable of initiating a directional object when a trigger of the FCU is pulled. The grip module, in some aspects, includes a hand grip, FCU housing, and rear stabilizing connector wherein the FCU housing is configured to house a removable FCU. The rear stabilizing connector, for example, is capable of coupling to a rear attachment for enhancing stability of the modified assembly. In alternative embodiments, the modified assembly further includes a slide assembly, barrel, barrel block, bolt, and return spring situated in the vicinity of the FCU for facilitating object launching process.

Abstract: A sound suppressor assembly for use in providing a means to a firearm silencer/suppressor designer with an alternative technology to create a more effective device. A sound suppressor assembly comprising a substantially smaller and more versatile device than analogous devices of existing technology. A sound suppressor assembly comprising a monolithic baffle for use in trapping burning and unburned propellant, and thus, distributing heat to avoid damage to said sound suppressor assembly. A sound suppressor assembly for use in facilitating easier and more efficient disassembly and cleaning, while simultaneously being able to handle substantially high pressure ammunition.

Abstract: Apparatus, systems, and methods for the maintenance, repair, modification, cleaning, disassembly, and reassembly of firearms and firearm components are disclosed. Particular embodiments include tools to aid in the removal and insertion of an extractor pin from the bolt assembly of an AR-15 or M-16 rifle. Preferred embodiments are directed to bolt assemblies for 0.223 and 0.308 imperial caliber firearms, as well as 5.56 and 7.62 metric caliber firearms. The tools include a housing with a channel to receive the bolt, a channel to insert a locking rod to orient and secure the bolt in the housing, a channel for inserting a removal rod to remove the extractor pin from the bolt or an inserting rod to insert the extractor pin into the bolt.

Abstract: In some embodiments, a bow comprises a first limb supporting a first rotatable member. The first rotatable member comprises a first bowstring track and a first terminal post. A second limb supports a second rotatable member. The second rotatable member comprising a second bowstring track and a second terminal post. A bowstring comprises a first end attached to the first terminal post and a second end attached to the second terminal post. The first bowstring track and the second bowstring track are oriented in a bowstring plane, and the first terminal post is laterally offset from the bowstring plane.

Abstract: A liquid dispensing squirt device comprises a handle member, a barrel/loading member, and a spray nozzle member. The barrel/loading member connects to the top portion of the handle member, and contains an access hatch where the carbonated beverage is held. The liquid from the carbonated beverage can is dispensed through the spray nozzle with the can is pierced.

Abstract: A removable grip is disclosed. The removable grip contains a magazine well adapted to receive a magazine, wherein the magazine well is nonoperational.

Abstract: A holster for receiving an integrally suppressed handgun having a trigger guard and a complementary interlocking feature located forward of a forward-most end of the trigger guard. The holster comprising a holster body having a forward end, a rearward end, and a holster wall extending therebetween. The holster wall defining a cavity extending along a handgun receiving and withdrawal axis. The holster including a retention mechanism comprising a lever pivotally supported by the wall of the holster body with the lever being pivotable about a pivot axis. A blocking member of the lever being dimensioned and adapted to be received in the complementary interlocking feature of the handgun. The lever being positioned so that the blocking member extends through an aperture and into the forward portion of the cavity at least when the lever is in the blocking position.

Abstract: The disclosure relates to a viewing optic. In one embodiment, the disclosure relates to a viewing optic having an integrated display system. In one embodiment, the disclosure relates to a viewing optic having an integrated display system for generating images that are projected into the first focal plane of an optical system.

Abstract: Provided is an illuminated dot reticle for use in a rifle scope having an optical path defined through axially spaced-apart objective and ocular lenses and method manufacturing a reticle disc assembly. A reticle disc has a first surface facing the objective lens and a second surface facing the ocular lens. A first reticle pattern, including a central aiming point, is applied to one of the reticle disc surfaces. An optical fiber has a proximal end portion and a distal end, with a light source configured to deliver light to the proximal end portion of the optical fiber. The optical fiber is secured to one of the reticle plate surfaces such that the distal end is positioned to transmit light from the light source toward the ocular lens in the optical path, providing an illuminated dot at the central aiming point.

Abstract: The present invention relates to target acquisition and related devices, and more particularly to telescopic gunsights and associated equipment used to achieve shooting accuracy at, for example, close ranges, medium ranges and extreme ranges at stationary and moving targets.

Abstract: The disclosure relates to a viewing optic. In one embodiment, the disclosure relates to a viewing optic having an integrated display system. In one embodiment, the disclosure relates to a viewing optic having an integrated display system for generating images that are projected into the first focal plane of an optical system.

Abstract: A protective device and method of design to protect against multiple blast and impact events for use in any application in which a delicate target has to be protected. The protective device for mitigating the effects of blast or impact employs a first layer having a first acoustic impedance and a second layer having a second acoustic impedance. The second acoustic impedance is different than the first acoustic impedance. The second layer is proximate to the first layer. The first layer and the second layer are chosen collectively to tune the stress waves from the blast or impact events to one or more specific tuned frequencies. A third layer of a visco-elastic material is employed having a critical damping frequency that matches one or more specific tuned frequencies to dissipate the stress waves of the blast and impact event. The third layer is proximate to the second layer.

Abstract: A tuning and mitigation system and method for mitigating a blast or impact event having an elastic layer having an acoustic impedance chosen to tune stress waves resulting from the blast or impact to one or more specific tuned frequencies, and a dissipative layer made of a viscoelastic material having a critical damping frequency that matches at least one or more specific tuned frequencies.

Abstract: A vehicle comprises ? a composite passenger compartment (1) comprising a structural shell formed wholly or in part of a glass fibre containing composite material comprising a plurality of layers of fibrous material bonded with a resin;? applique armour (5-9) mounted to the composite passenger compartment wherein the plurality of layers of fibrous material comprise both glass fibres and fibres providing in composite form a greater ballistic resistance per unit mass than the glass fibre.

Abstract: A downhole explosive detonation assembly with a high voltage electro-explosive initiator having an input high voltage power supply with a low impedance shunting fuse, a flexible electrical link and a capacitor discharge unit. The explosive detonation assembly is adapted to detonate detonating cord from the side.

Abstract: A cartridge with an expanding bullet that has advantageous terminal effects over an extended range. The expanding bullet including a bullet body including a metal jacket extending from a tail portion to a nose portion and surrounding an interior solid core and defining a forward opening and interior cavity. A tip has an exterior surface substantially flush with an exterior surface of the metal jacket. The tip has a main portion forward of the opening and a tip retention portion that at least partially fills the interior cavity. In certain embodiments the tip retention portion includes one or more fluid entry facilitation means such as a fracture regions configured to, upon impact of the bullet with a target, fracture or deform to expose one or more fluid pathways into the interior cavity and to a forward facing interior surface for initiating expansion of the expanding bullet.

Abstract: A projectile with a projectile casing and at least one pyrotechnic charge incorporated in the projectile casing is proposed, wherein the projectile has an open projectile base with a destructible membrane and the pyrotechnic charge burns away at a defined rate during the flight of the projectile, and so the projectile loses mass in such a way that a predetermined effective range is not exceeded. As a result, safety and a nonlethal effect are achieved, in particular outside the effective range.

Abstract: A penetrator and a sub-caliber ammunition or projectile accommodating said penetrator. The penetrator according to the invention is characterized by the fact that the penetrator has an interface in the front area. Via said geometric interface, a basic penetrator devised in according to the invention can be provided having different penetrator tips and completed to form an individual KE penetrator.

Abstract: A new and novel non-lethal pellet shaped marking round for use with air rifles or air pistols, which utilizes the technology and ballistics of a bullet-shaped pellet projectile, and is designed to travel through a rifled barrel or a polygonal rifling barrel. Also disclosed is a novel non-lethal marking round pellet designed with grooves which imitate the spiral caused by a rifled barrel while utilizing a smooth bore barrel.

Abstract: One embodiment of the present invention provides a polymeric ammunition cartridge and methods of making and using the same. The cartridge includes a substantially cylindrical insert connected to a substantially cylindrical polymeric middle body. The substantially cylindrical insert includes a top surface opposite a bottom surface and a substantially cylindrical coupling element that extends from the bottom surface, a primer recess in the top surface that extends toward the bottom surface, a primer flash hole positioned in the primer recess to extend through the bottom surface, and a flange that extends circumferentially about an outer edge of the top surface.

Abstract: The present invention provides a polymeric ammunition cartridge comprising: a three piece primer insert; a substantially cylindrical polymeric middle body extending about the three piece primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers an circumferential surface of the primer flash hole aperture; and a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet.

Abstract: The present invention provides polymeric ammunition cartridge comprising: a three piece primer insert; a substantially cylindrical polymeric middle body extending about the three piece primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers an circumferential surface of the primer flash hole aperture; and a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet.

Abstract: The present invention provides a polymeric ammunition comprising: a three piece primer insert; a substantially cylindrical polymeric middle body extending about the three piece primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers an circumferential surface of the primer flash hole aperture; and a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet.

Abstract: The present invention provides polymeric ammunition comprising: a three piece primer insert; a substantially cylindrical polymeric middle body extending about the three piece primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers an circumferential surface of the primer flash hole aperture; and a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet.

Abstract: The present invention provides a three piece primer insert for use in polymer ammunition comprising: an upper primer insert portion comprising an upper primer bottom surface, an upper primer aperture through the upper primer bottom surface, a groove positioned around the upper primer aperture, wherein the groove is adapted to receive a polymer overmolding and a substantially cylindrical coupling element extending away from the upper primer bottom surface; a middle primer insert portion comprising a middle aperture and positioned in contact with the upper primer bottom surface and adjacent to the groove, wherein the middle aperture is smaller than the upper primer aperture; and a lower primer insert portion in contact with the middle primer insert portion comprising a lower primer bottom surface in contact with the middle primer insert portion and opposite a lower primer top surface, a primer recess in the lower primer top surface that extends toward the lower primer bottom surface and adapted to fit a primer,

Abstract: The present invention provides a polymeric ammunition comprising: a three piece primer insert; a substantially cylindrical polymeric middle body extending about the three piece primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers an circumferential surface of the primer flash hole aperture; and a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet.

Abstract: The present disclosure describes an electronic ignition circuit (“EIC”) for controlling at least one detonator. The EIC may include a protection circuit, an input circuit coupled to the protection circuit, a logic circuit electrically coupled to the input circuit, and an ignition circuit electrically coupled to the logic circuit. The protection circuit may include at least one of a fuse, a circuit breaker and an automatic switch. The logic circuit may include an answer back circuit, and a switching circuit adapted to switch to the next detonator or igniter. The ignition circuit may include a capacitor charging circuit, a capacitor discharge circuit to discharge a firing capacitor through a fuse head, and a shot detection circuit adapted to measure a voltage across the firing capacitor before discharging through the fuse head and to measure a voltage after discharging through the fuse head.

Abstract: A method of inhibiting a blast from an explosive (7) comprising the steps of (a) providing a blast inhibiting blanket (1), the blast inhibiting blanket (1) comprising first and second water porous outer layers (2, 3) and an absorbent core /4) sandwiched therebetween, said absorbent core (4) comprising an absorbent crystalline material and an absorbent fibrous material; (b) arranging the blast inhibiting blanket (1) to cover the explosive (7) but spaced apart therefrom; and, (c) wetting the blast inhibiting blanket (1) either before or after arranging the blanket (1) to cover the explosive (7).

Abstract: Containment vessels are adapted to facilitate blast and dispersion mitigation. According to one example, a containment vessel may include at least one containment layer. At least one expansion member may be coupled to the at least one containment layer to apply a force sufficient to expand a perimeter of the containment layer(s) laterally outward. A closure system may be coupled with the containment layer(s), where the closure system is configured to cinch the perimeter of the containment layer(s) around a target object without manual intervention. Unmanned aerial vehicle (UAV) including a containment vessel, as well as methods of making a containment vessel are also disclosed. Other aspects, embodiments, and features are also included.

Abstract: A tool, such as a tape measure, including a spring-based retraction system is shown. The spring-based retraction system is driven by a spiral spring, that has a variable preformed stress profile along the length of the spring.

Abstract: A tape measure includes a housing having a wall defining an internal cavity and a tape port, a coilable measuring tape disposed within the internal housing and having a first end extendable out of the housing, and an end hook member including an attachment portion and a hook portion. The attachment portion is arranged to engage the first end of the tape to attach the end hook member to the tape. The hook portion extends in a direction normal to the attachment portion and includes a first face and a second face arranged to engage the workpiece. A finger guard extends from the housing, and is configured to engage the hook member, and a finger space is defined between the tape port and the finger guard and is arranged to receive a user's finger during operation of the tape measure such that the user's finger engages the measuring tape.

Abstract: An assembly for measuring wear of a barrel and feedscrew combination, wherein the barrel has a longitudinally extending feedscrew disposed therein and a radially extending measuring aperture formed in a wall thereof, includes a measuring probe having a proximity detecting sensor, a barrel plug for removable insertion into the measuring aperture, and a measuring fixture. The barrel plug is configured to undergo wear in an axial direction thereof while inserted into the measuring aperture. The measuring probe and the barrel plug are installed into the measuring fixture for determining wear of the barrel plug in the axial direction thereof. The measuring probe is further configured for removable insertion into the measuring aperture for measuring wear of a flight of the feedscrew. A spacer and rotational tool cooperate with the measuring probe when installing the measuring probe in the measuring aperture.

Abstract: A phase-resolved heterodyne shearing interferometer has been developed for high-rate, whole field observations of transient surface motion. The sensor utilizes polarization multiplexing and multiple carrier frequencies to separate each segment of a shearing Mach-Zehnder interferometer. Post-processing routines have been developed to recombine the segments by extracting the scattered object phase from Doppler shifted intermediate carrier frequencies, providing quantitative relative phase changes and information to create variable shear, phase resolved shearographic fringe patterns without temporal or spatial phase shifting.

Abstract: The invention provides for generating a set of signature signals that correspond to a range of depths within a target. These signature signals can include multiple individual reference signals and be can modified to compensate for specific characteristics of the target. In the preferred embodiment the members of the set of signature signals are correlated with data sets by phase rotating individual reference signals to determine maximum and minimum correlation and thereby enabling determination of the scattering characteristic of the target at each depth. Also a pilot signal is monitored to dynamically determine the phase relationship between individual reference signals and thereby avail of phase sensitive detection techniques to enhance SNR at deeper regions where multiple individual reference signals exist.

Abstract: A vapor phase growth rate measuring apparatus has an initial parameter setting adjuster to set initial values of fitting parameters, a refractive index of each thin film to be formed on the substrate, a growth rate of each thin film, and at least one parameter having temperature dependence, a film thickness calculator to calculate a film thickness of each thin film, a parameter selector to select a value in accordance with a growth temperature for the parameter, a reflectometer to measure a reflectance of the substrate, a reflectance calculator to calculate a reflectance of the substrate, an error calculator to calculate an error between the calculated reflectance and an actual measurement value of the reflectance measured at a plurality of times, a parameter changer to change at least a part of the values of the fitting parameters, and an output value generator to generate characteristic values of each thin film.

Abstract: A shape calculating apparatus includes a light source and a light guide provided with detection targets to decrease quantity of light guided by the light guide according to a bend shape of the light guide. The apparatus also includes a light detector to detect light quantity information in wavelengths included in light absorption spectra of the detection targets, a calculation unit that makes a calculation relating to a shape of each detection target based on the light quantity information, and a control unit that changes a dynamic range of at least one of an intensity of light input to the light guide and a detection signal output by the light detector for each wavelength range so that a magnitude of the detection signal is within a range between a lower limit threshold and an upper limit threshold of the light detector.

Abstract: A three-dimensional (3D) measuring system includes a triangulation scanner having a projector and a first triangulation camera, the projector including a first circular polarizer, the first triangulation camera including a second circular polarizer, the second circular polarizer having handedness opposite the first circular polarizer.

Abstract: The present disclosure describes systems and processes, including processes in which first location data is received. Visual access to a first image corresponding to the first location data is provided, the first image including a roof structure of a building. A first computer input capable of signaling a designation from the user of a building roof structure location within the first image is provided. A designation of the building roof structure location within the first image is received. Responsive to receiving the designation of the building roof structure location, a second computer input capable of signaling user-acceptance of the building roof structure location within the first image is provided. Responsive to receiving the user-acceptance confirming the designation of the building roof structure location, visual access to one or more second images corresponding to geographic location coordinates of the building roof structure location is provided.

Abstract: An electro-magnetic brake which is switched between an operative braking position and an inoperative position by transient pulses of current. It is held passively in the operative and inoperative positions with little or no current. This prevents the generation of heat, which would affect the accuracy of measurements where the brake is used in dimensional measuring equipment. In one form, permanent and semi-permanent magnets are arranged in parallel, and the magnetic polarity of the arrangement is flipped by transient current pulses in a surrounding coil. A capacitor may provide a reservoir of current to activate the brake in the event of a power supply failure.