433 results about "Crosswind" patented technology

A crosswind kite system adapted to operate in an alternate mode in high winds. The system may operate at reduced efficiency in high winds in order to moderate loading on the system during those high winds. The system may use multi-element airfoils which are actuated to reduce the coefficient of lift of the airfoils in order to moderate loading in high wind conditions. Other flight aspects may be controlled, including flying the crosswind kite in side slip to induce drag which may lower loading on the system.

A reticle of a projectile weapon aiming system such as a riflescope includes a primary aiming mark adapted to be sighted-in at a first selected range and further includes a plurality of secondary aiming marks spaced apart below the primary aiming mark. The secondary aiming marks are positioned to compensate for ballistic drop at preselected incremental ranges beyond the first selected range, for a selected group of ammunition having similar ballistic characteristics. Angles subtended by adjacent aiming marks of the reticle can be adjusted by changing the optical power of the riflescope, to thereby compensate for ballistic characteristics of different ammunition. In some embodiments, the reticle includes a set of windage aiming marks spaced apart along at least one secondary horizontal axis intersecting a selected one of the secondary aiming marks, to facilitate compensation for the effect of crosswinds on the trajectory of the projectile.

A reticle of a projectile weapon aiming system such as a riflescope includes a primary aiming mark adapted to be sighted-in at a first selected range and further includes a plurality of secondary aiming marks spaced apart below the primary aiming mark. The secondary aiming marks are positioned to compensate for ballistic drop at preselected incremental ranges beyond the first selected range, for a selected group of ammunition having similar ballistic characteristics. Angles subtended by adjacent aiming marks of the reticle can be adjusted by changing the optical power of the riflescope, to thereby compensate for ballistic characteristics of different ammunition. In some embodiments, the reticle includes a set of windage aiming marks spaced apart along at least one secondary horizontal axis intersecting a selected one of the secondary aiming marks, to facilitate compensation for the effect of crosswinds on the trajectory of the projectile.

A gunsight reticle defines a system of dimensioned indicia spaced at specific separations to improve aiming accuracy of a gun. The indicia may include perpendicularly intersecting center vertical and center horizontal hairlines, and four (or more or less) horizontal range-marker lines disposed at specific angular separations below the horizontal hairline in bisected relationship with the center vertical hairline. Spacing of the range marker lines below the center horizontal hairline is proportional to bullet drop at selected ranges, depending upon ballistic characteristics of bullet used. Relative lengths of said range-marker bars on each side of the central vertical crosshair are proportional to a specific crosswind (say 10 mph) at target range reflected by respective range marker. The method involves employing this reticle to determine distance to target, and using distance thus determined to ascertain a precise aiming point on the reticle. These indicia also have other useful characteristics that allow the shooter to easily mentally calculate corrections for crosswind, moving targets and shooting at targets that are above or below the shooter at a significant angle.

Within an intake for a gas turbine engine provision is provided through stator vanes 25, 45 in the stator whereby back pressure from a necessary obstruction 34, 46 can be utilised to balance forward pressure variations caused by intake droop or crosswinds in order to reduce those forward pressure detriments for more efficient engine operation according to a desired objective regime. Typically the flow through the intake 20 is analysed and then an appropriate positioning of the stator vanes 25, 45 determined in order to provide approximate balance between the forward pressures and back pressures. Normally, a combination of camber variation of stator vanes 45a and stagger variation of stator vanes 45b are utilised in order to achieve a desired momentum balance around the circumference of the intake 20. It will be understood that both the forward pressures and the back pressures are differentially variable about the circumference such that one opposes the other.

According an embodiment, a projectile weapon aiming system includes a computer-controllable reticle with crosshairs or other aiming marks having a color and / or illumination that can be selectively changed to provide feedback to a shooter to indicate when the projectile weapon aiming system (and hence the projectile weapon itself) is accurately aimed to compensate for a particular range, inclination, crosswind, and / or other ballistic conditions.

The invention provides a side wind resistance landing flight track tracking control method based on side direction guide, which belongs to the flight track tracking control technology of airplanes landed under the side wind condition. The flight track tracking control method based on side direction guide is adopted, and comprises the following steps: calculating the inner ring posture control commands through a side direction guide law by the flight track tracking side direction deviation; generating steering engine control commands by an inner ring posture controller for controlling the airplane posture; and calculating the current side direction deviation by the flight line switching logics according to the current state of the airplane for the side direction guide law calculation. A transverse side direction movement model of the airplane is used for simulating the dynamic and kinematic model of the airplane. When being adopted, the side direction flight track control system based on the ground speed guide has better inhabitation effect on the side wind phenomena such as side direction gust wind, air turbulence, side direction wind shear and the like when the airplane is landed. At the same time, the side direction flight line switching logics can also meet the requirement of approach flight of the airplane under the side wind condition.

A system and methods for reducing aerodynamic drag and mitigating detrimental side wind effects on vehicles moving through air or water with a plurality of new subsystems disposed in a plurality of locations on the vehicles. Each one of the subsystems includes a sub-set of small-scale vortex generators that have an intake for air from airflow around the vehicle and that produce intensive small-scale vortices with large lifespan, and / or a new fairing device that streamlines airflow and produces a sheet of small-scale-vortices. The subsystems direct the vortices with large lifespan and / or sheets of vortices into the vehicle's drag-producing volumes. The vortex generators have one or several air channels preventing airflow from bypassing vortex-producing elements and the elements inside the channels that produce small-scale vortices. The novel fairing devices are of bluff shape and / or with bluff obstructions and / or slots for generating sheets of intensive small-scale vortices in surrounding airflow.

A vehicle traveling through an environmental media such as air experiences drag. The drag is actively modulated by energy beams which may either increase or decrease the drag. The energy beams may provide either a chemical, acoustic or electromagnetic energy at a transition region between turbulent and laminar flows or at the leading edge of a laminar flow or in the direction of a crosswind in order to facilitate the respective increase or decrease in drag. If the vehicle is a sailing ship, areas of the sails are selectively roughened or widened to enhance the thrust derived from the wind. Furthermore, the keel or hull of the sailing ship may be modified to improve the hydrodynamic characteristics of the sailing ship. If the vehicle is an automobile, the tires or road surface may be selectively heated to improve the traction of the automobile. Furthermore, the energy beams may be used to facilitate atomization of the air / fuel mixture prior to combustion in an internal combustion engine thereby improving the thrust of provided to the vehicle. Energy beams may be used to generate virtual extensions of a vehicle to enhance traveling efficiency.

An electro-optic system, e.g., mounted to a weapon, measures down range winds and a range-to-target for compensating the ballistic hit point. The system may include an optical light source, collimated to generate a laser spot on the target. The system may include a wind measurement receiver that captures laser light scattered from the target. The captured light may be modulated by atmospheric scintillation eddies, producing optical patterns which change in time and move with the crosswind. These patterns may be analyzed by a processor using covariance techniques to determine path-integrated crosswinds and associated errors. Ranging is done by measuring the time of flight of the laser pulse to the target collecting the scattered signal from the target. Compensated ballistic hit point, measurement errors and other data may be displayed on a micro-display digital eyepiece, overlaid on the real-time image of the target.

An electro-optic system, e.g., mounted to a weapon, measures down range winds and a range-to-target for compensating the ballistic hit point. The system may include an optical light source, collimated to generate a laser spot on the target. The system may include a wind measurement receiver that captures laser light scattered from the target. The captured light may be modulated by atmospheric scintillation eddies, producing optical patterns which change in time and move with the crosswind. These patterns may be analyzed by a processor using covariance techniques in either the time-domain or the frequency-domain to determine path-integrated crosswinds and associated errors. Ranging is done by measuring the time of flight of the laser pulse to the target collecting the scattered signal from the target. Compensated ballistic hit point, measurement errors and other data may be displayed on a micro-display digital eyepiece, or projected onto the direct view optics (DVO) of a riflescope so as to be overlaid in real-time on the optical image of the target.

An electro-optic system, e.g., mounted to a weapon, measures down range winds and a range-to-target for compensating the ballistic hit point. The system may include an optical light source, collimated to generate a laser spot on the target. The system may include a wind measurement receiver that captures laser light scattered from the target. The captured light may be modulated by atmospheric scintillation eddies, producing optical patterns which change in time and move with the crosswind. These patterns may be analyzed by a processor using covariance techniques in either the time-domain or the frequency-domain to determine path-integrated crosswinds and associated errors. Ranging is done by measuring the time of flight of the laser pulse to the target collecting the scattered signal from the target. Compensated ballistic hit point, measurement errors and other data may be displayed on a micro-display digital eyepiece, or projected onto the direct view optics (DVO) of a riflescope so as to be overlaid in real-time on the optical image of the target.

The invention discloses a vertical takeoff and landing unmanned aerial vehicle with foldable fixed wings based on a dual-duct fan power system. A dual-duct fan power system which is horizontally arranged at the tail of the body of the unmanned aerial vehicle in a tail-driving arrangement is adopted, so that lifting force for vertical takeoff and landing and thrust for horizontal flying are provided for an aircraft; a control surface which is arranged at the exit of each duct in a deflected manner is used for providing vector thrust, so that quick attitude change is realized; wings adopt a folding wing configuration, when the aircraft vertically takes off and lands / flies at a low speed, the wings are folded to decrease the frontal area of cross wind, and when the aircraft flies horizontally, the wings are unfolded to obtain large lifting force; and combined optimization of ducts and the wings is adopted, the wings are arranged in a specific duct air flow region, the duct suction generates a Coanda effect at a wing edge, so that the properties of the wings are improved. Multi-mold flight tasks such as vertical takeoff and landing, high-speed cruise, and the like of the aircraft are realized; the vertical takeoff and landing aircraft is high in aerodynamic efficiency during hanging in the air / flying at a low speed; and the vertical takeoff and landing unmanned aerial vehicle is high in anti-disturbance capacity during takeoff and landing / hanging in the air. The vertical takeoff and landing unmanned aerial vehicle is low in energy consumption, small in noise and high in safe reliability.

The invention discloses a variable-ship-length-rate-based crosswind-resistant straight path tracking method of an unmanned surface vessel. In view of different influences on path tracking by different ship length rates, a variable-ship-length-rate-based straight path tracking method is put forward based on combination with fuzzy control. The range deviation and a changing rate of the range deviation are used as inputs of a fuzzy controller and the ship length rate is used as the output of the fuzzy controller; the ship length rate is adjusted dynamically, thereby adjusting a course angle to adjust LOS-principle-based input and output parameters of a PD controller of a tracking expected course angle alpha fai. Voltages of motors at the left side and the right side of the unmanned surface vessel are controlled, thereby realizing straight path tracking of the unmanned surface vessel in a water-surface crosswind environment. Besides, with a course correction and error compensation method, static error occurrence caused by path tracking in a crosswind environment is reduced and a straight path tracking effect of the unmanned surface vessel in an anti-interference environment is improved.

The invention relates to a crosswind information estimation method based on the unmanned aerial vehicle crabbing method. The crosswind information estimation method based on the unmanned aerial vehicle crabbing method comprises the following steps that test data generated during unmanned aerial vehicle crabbing are obtained; the obtained test data are processed; crosswind information estimation is conducted according to the relation between the yaw angle phi and the track angle phi <s> and the relation between the airspeed Va and the ground speed Vd, wherein crosswind information includes the amplitude of crosswind and the crosswind azimuth angle relative to the geomagnetic true north, and a certain included angle exists between the pointing direction of the head of an unmanned aerial vehicle and the crosswind. According to the crosswind information estimation method based on the unmanned aerial vehicle crabbing method, the requirement for real-time crosswind estimation in an unmanned aerial vehicle flight test can be met, the crosswind applied to the unmanned aerial vehicle when the unmanned aerial vehicle flies flat can be measured quite accurately by analyzing the speed relation existing when the unmanned aerial vehicle crabs, the safety coefficient is increased when the unmanned aerial vehicle flies, and the completeness of information is guaranteed.

A reticle of a projectile weapon aiming system such as a riflescope includes a primary aiming mark adapted to be sighted-in at a first selected range and further includes a plurality of secondary aiming marks spaced apart below the primary aiming mark. The secondary aiming marks are positioned to compensate for ballistic drop at preselected incremental ranges beyond the first selected range, for a selected group of ammunition having similar ballistic characteristics. Angles subtended by adjacent aiming marks of the reticle can be adjusted by changing the optical power of the riflescope, to thereby compensate for ballistic characteristics of different ammunition. In some embodiments, the reticle includes a set of windage aiming marks spaced apart along at least one secondary horizontal axis intersecting a selected one of the secondary aiming marks, to facilitate compensation for the effect of crosswinds on the trajectory of the projectile.

The invention relates to the technical field of IT and discloses a cabinet server and a control method of the cabinet server. The cabinet server comprises a cabinet, a rotating speed acquisition device, a temperature acquisition device and a controller. Multiple separation boards are arranged in the cabinet so that multiple air ducts can be formed, and each air duct is internally provided with a fan; the air ducts are arranged in at least one air duct set, each air duct set comprises one convertible air duct and two side air ducts; air outlets of the convertible air ducts are provided with air outlet baffles; the separation boards between the side air ducts and the convertible air ducts are provided with ventilation openings and ventilation opening baffles; the controller is in signal connection with the rotating speed acquisition device and the temperature acquisition device and can control the rotating speed of the fans in the convertible air ducts and the rotating speed of the fans in the side air ducts according to information acquired by the rotating speed acquisition device and the temperature acquisition device, so that the ventilation openings are controlled to be opened or closed through the ventilation opening baffles. When the heat dissipation condition is met, the noise of the fans is the lowest when the cabinet server works.

The invention discloses a cruise stage fuel consumption prediction method for aircraft mass change. The method comprises the following steps: step 1, considering the influence of mass change and crosswind, and constructing a cruise stage fuel consumption model; step 2, aiming at the model constructed in the step 1, establishing an objective function and constraint conditions; and step 3, solving the optimal solution of the objective function to obtain the optimal fuel mileage under each mass and the corresponding optimal cruise height and maximum cruise Mach number. According to the prediction method, a cruise fuel consumption prediction model based on aircraft mass change can be established, and the optimal cruise height and the optimal cruise speed corresponding to the maximum fuel mileage of different aircraft masses are determined through optimization calculation by the model.

An improved electronic aiming device for use with a weapon or other manually aimed device. Means are provided to vary the field of view, determine range to target, compensate for bullet drop, and to compensate for crosswind, without removing either hand from the weapon, by monitoring the tilt of the weapon upon which the device is mounted.