39 results about "True airspeed" patented technology

A system and method are provided for calculating Mach number and true airspeed without reference to data from a pitot static sensor. The true airspeed and Mach number are calculated using the altitude information from GPS, IRS, Radio Altimeter and other onboard sensors other than the air data computer (ADC). The computed true airspeed or Mach number could be used to confirm the ADC information or in lieu of the ADC information when the ADC information is unreliable or unavailable.

The object of the present invention is to provide an air data sensor that does not require an external input of a reference velocity as a Doppler LIDAR, has a function of autonomously determining the absolute airspeed, and has no position error. The optical air data sensor in accordance with the present invention is an optical air data sensor, mounted on an aircraft, for emitting a laser light as a transmission light into atmosphere, and then receiving a laser scattered light produced by scattering of the laser light by aerosol present in the atmosphere as a reception light, thereby to measure an airspeed and a wind velocity of airflow in a distant region on the basis of a Doppler shift amount between the transmission light and the reception light, wherein a true airspeed is autonomously measured, without setting a reference velocity, by successively sweeping a frequency offset corresponding to a reference velocity for providing an offset to a measurement frequency, and performing this sweeping within a frequency range in which the Doppler shift amount is measured.

The invention discloses an estimation method of an atmosphere angle of attack and an angle of sideslip in a high-angle-of-attack flight status. Under the premise that the structure of an aircraft is not changed and additional measuring devices and hardware devices are not added, the parameters output by the existing onboard strapdown inertial navigation system, a GPS (Global Position System) system, a flight control system and a fuel measuring system are fully used for resolving the angular acceleration, the rotational inertia, the product of inertia, the coefficient of a moment equation set and the total mass of the aircraft; based on a flight dynamics model, by establishing an extended Kalman filter, and integrating the processes of resolving the flight dynamics model and the status estimation together, accurate estimation of the current angle of attack, the angle of sideslip and the true airspeed is realized, and then the current air speed and the change rate of the air speed are resolved and input into the extended Kalman filter as the feedback information so as to finish the real-time accurate estimation of the angle of attack and the angle of sideslip of next time; the real-time accurate estimation of the angle of attack and the angle of sideslip is realized by a recursive resolving mode, measurement range and measurement precision of an atmosphere data system are improved, and adaptability to complex flight environment is also improved.

A navigation and guidance computer system using navigation sensors to determine aircraft position, and automatically control the aircraft to fly from an initial position to intercept and follow a crew-selected rendezvous orbit in accordance with Air Traffic Control and military specified rules. It creates maneuvers that result in smooth, efficient motion of the aircraft from an initial position to the execution of a rendezvous orbit. It controls the aircraft by applying commands to the aircraft's autopilot. The system creates the smooth and coordinated maneuvers by considering and anticipating all constraints on the aircraft flight path by creating a single maneuver that is a re-entry maneuver, an over fly maneuver, and a turning maneuver all as a single turn that is contained entirely within the allowable airspace. All maneuvers are created and executed recognizing the turning capability of the aircraft considering allowable bank angles, current wind conditions and true airspeed.

A system and method are provided for calculating Mach number and true airspeed without reference to data from a pitot static sensor. The true airspeed and Mach number are calculated using the altitude information from GPS, IRS, Radio Altimeter and other onboard sensors other than the air data computer (ADC). The computed true airspeed or Mach number could be used to confirm the ADC information or in lieu of the ADC information when the ADC information is unreliable or unavailable.

A system for calculating airspeed and dynamic pressure comprises a system body, an internal accelerometer, located within the system body, an internal pressure sensor, located in the system body, the internal pressure sensor being not hermetically sealed within the system body and capable of measuring the static pressure of the ambient atmosphere, and a processor in reception of the internal accelerometer, and the internal pressure sensor, capable of calculating Mach number via an axial acceleration, and capable of calculating a dynamic pressure and a true airspeed via the Mach number.

The object of the present invention is to provide an air data sensor that does not require an external input of a reference velocity as a Doppler LIDAR, has a function of autonomously determining the absolute airspeed, and has no position error. The optical air data sensor in accordance with the present invention is an optical air data sensor, mounted on an aircraft, for emitting a laser light as a transmission light into atmosphere, and then receiving a laser scattered light produced by scattering of the laser light by aerosol present in the atmosphere as a reception light, thereby to measure an airspeed and a wind velocity of airflow in a distant region on the basis of a Doppler shift amount between the transmission light and the reception light, wherein a true airspeed is autonomously measured, without setting a reference velocity, by successively sweeping a frequency offset corresponding to a reference velocity for providing an offset to a measurement frequency, and performing this sweeping within a frequency range in which the Doppler shift amount is measured.

A method and aircraft system are provided for determining an optimal gliding speed that maximizes gliding distance of the aircraft upon engine failure, and comprises calculating the optimal gliding speed from a speed polar curve, true airspeed, heading, and vertical wind speed. The polar curve may be constructed with consideration of the aircraft center of gravity and weight. The calculated gliding speed, which may be restricted to a threshold, is provided to the pilot and optionally to an autopilot. The method is repeated periodically, or if the wind vertical or horizontal velocities exceed a threshold for a predetermined period of time.

An inertial navigation system which includes a first control system and a second control system is described. The first control system is configured to estimate a vertical velocity based in part on received vertical acceleration data. The second control system is configured to receive the estimated vertical velocity from the first control system and determine a compensated vertical velocity utilizing the estimated vertical velocity and airspeed.

The invention relates to a bionic polarization / inertial / atmospheric data integrated navigation system. The system consists of a navigation sensor, a solving module, an interface circuit, a microprocessor, a storage module and a power supply module. The sensor is composed of a biomimetic polarization sensor, an inertial measurement unit and an atmospheric data system. Specifically, the bionic polarization sensor includes an optical camera, a motor, a polarizing device and other components, and the atmospheric data system is composed of a pitot-static sensor, a pitot-static pipeline and a totaltemperature circuit. The work flow includes that: the sensor module collects the polarized light information, atmospheric static pressure, full pressure and other data in the atmospheric environment,and transmits the data to the solving module, and the processor determines whether the sensor works reliably, selects a working mode, and works out the course angle, true airspeed, height and other information for compensation correction of the attitude and speed of the navigation system, and stores and outputs navigation parameters. The integrated navigation system provided by the invention has the advantages of flexible navigation mode, strong autonomy, small volume and the like, and has interference suppression, fault detection and system reconstruction functions.

A flight display for an aircraft includes a virtual ice accretion meter having a liquid water content portion and an ice thickness portion. A method for determining ice accretion includes integrating over a time period a constant K multiplied by a liquid water content (LWC) and true airspeed (TAS).

An inertial navigation system which includes a first control system and a second control system is described. The first control system is configured to estimate a vertical velocity based in part on received vertical acceleration data. The second control system is configured to receive the estimated vertical velocity from the first control system and determine a compensated vertical velocity utilizing the estimated vertical velocity and airspeed.

The invention belongs to the aviation meteorology field and discloses an updraft measurement method of an airplane used in weather modification. By using a traditional method, updraft can not be settled. In the invention, the above problem is solved. The method comprises the following steps of 101, acquiring the true airspeed Vt, the angle of attack alpha and the sideslip angle beta of fixed wingairplane flight; 102, converting a vector VtSb=(VtX, VtY, VtZ) into a ground coordinate system from a body coordinate system; 103, acquiring the three-dimensional ground speeds VgXg, VgYg and VgZg, the pitch angle theta, the roll angle phi and the course angle psi of the fixed wing airplane flight; and 104, in the ground coordinate system, subtracting a three-dimensional airspeed from a three-dimensional ground speed and acquiring the updraft. In the invention, the updraft can be accurately measured; the measurement of the updraft is performed in an artificial precipitation field, which can beused to determine an airflow direction and a size in cloud and can be used for precipitation work scheme making; and catalytic efficiency is increased.

The invention discloses a flight record system for a plane and a data processing method thereof, relates to the technical field of aircrafts, and aims to solve the technical problem involved in monitoring of plane working conditions. The system comprises a ground communication terminal as well as a self-contained power supply, an onboard satellite communication terminal and two trigger switches which are arranged on the plane, wherein the first trigger switch is a mechanical micro switch; the second trigger switch is a bipolar latch Hall switch; the onboard satellite communication terminal is connected with the ground communication terminal through a satellite; the power supply port of the onboard satellite communication terminal is connected to an onboard power supply and the self-contained power supply respectively through the two trigger switches; the first trigger switch is arranged in the undercarriage cabin of the plane, and is triggered to be switched on / off through an undercarriage; the second trigger switch is arranged in a true-airspeed meter, and is triggered to be switched on / off through two magnets arranged on the inner wall of a dial plate; flight working condition data can be transmitted to the ground communication terminal in real time through the onboard satellite communication terminal. The system and the method contribute to ground monitoring of the plane working condition.

The invention discloses a high-sensitivity optical-type airspeed measuring device which comprises an airspeed pipe, a shell body and an opening sylphon. An optical curve sensing unit is contained inside the shell body, wherein the optical curve sensing unit comprises a curve-type test channel and a measuring unit, the measuring unit is connected with a disposing unit, and the disposing unit is connected with a display unit. The curve-type test channel comprises a curve-type support, multiple side A transformation teeth and multiple side B transformation teeth. The multiple side A transformation teeth and the multiple side B transformation teeth are arranged in a crossing mode, and the curve-type test channel which is provided for one or more signal optical fibers passing is formed among heads of the multiple side A transformation teeth and the multiple side B transformation teeth. The multiple side A transformation teeth and the multiple side B transformation teeth are arranged on two sides of the signal optical fibers correspondingly. A movable point of the opening sylphon is fixedly connected with one end of the curve-type support, and the other end of the curve-type support is fixed on the inner wall of the shell body. The high-sensitivity optical-type airspeed measuring device is simple in structure, reasonable in design, convenient to process and manufacture, low in cost and flexible in using manner, high in sensitivity and good in using effect.

An Energy State Awareness System that alerts the pilot of an aircraft during the climb, cruise and descent phases of a flight of low airspeed conditions, and during the Approach / Landing and Go-Around phases of flight when airspeed has deviated from a pre-determined reference airspeed that is considered “Stable” for the flight conditions. In order to determine the degree of deviation, the system monitors some of various readily available signals representative of flight parameters and of the aircraft's configuration such as true airspeed, weight, flap position, center of gravity and normal load factor—nz. Some signals are used directly, others are used as inputs to internal algorithms that compute the data necessary to determine the magnitude of the deviations.

The present invention provides a method and system for optimizing rotor flapping, which utilizes the collective stick position and true airspeed to determine a commanded longitudinal stick position.

A method for measuring a windspeed vector is described. A true airspeed vector of a flying machine is measured while the machine is in flight using one or more nanowires on the flying machine. Each nanowire is configured to measure a value of local air velocity relative to the flying machine. A velocity of the flying machine relative to the ground is measured while the machine is in flight, and then (a) the true airspeed vector is subtracted from (b) the velocity of the flying machine relative to the ground. Other applications are also described.

The invention provides an atmosphere data ground testing system. The invention aims to provide a testing system which can test the dynamic characteristics of optical atmosphere speed sensors in a ground environment and has low requirements for environments. The technical solution of the invention is characterized in that an atmosphere data computer, a GPS / Beidou resolver and an inertial navigationapparatus are integrated in a case; a combined wind speed measurement apparatus measures the wind speed and direction of relative airflow in the horizontal direction and the vertical direction at measurement points to provide benchmark data of the true airspeed, angle of attack and angle of sideslip for an optical atmosphere speed sensor; a rotating platform changes the included angle between theoptical atmosphere speed sensor and the relative airflow by rotating a stipulated angle; the optical atmosphere speed sensor makes emitted laser beams converge at a focus, and the projection speed ofthe macroscopic atmosphere relative movement speed Vc in the axis direction of each laser beam at the focus is detected according to the principle of laser scattering; the projection speeds of more than three different directions are combined to obtain testing data.

The invention provides a true airspeed reconstruction strategy for an unmanned aerial vehicle. Under two conditions that a mach number fails and a total temperature sensor fails, true airspeed reconstruction is performed in different ways; when the mach number fails, the mach number reconstruction is performed according to the eastward speed, the northward speed and the skyward speed of a GPS and the GPS height; when the total temperature sensor fails, the true airspeed is directly obtained by look-up of a mach number and air pressure altimeter or the true airspeed is reconstructed according to the eastward speed, the northward speed and the skyward speed of the GPS. The true airspeed information validity is ensured, and the true airspeed is calculated by fully utilizing atmosphere data information and GPS data information.

A system for calculating airspeed and dynamic pressure comprises a system body, an internal accelerometer, located within the system body, an internal pressure sensor, located in the system body, the internal pressure sensor being not hermetically sealed within the system body and capable of measuring the static pressure of the ambient atmosphere, and a processor in reception of the internal accelerometer, and the internal pressure sensor, capable of calculating Mach number via an axial acceleration, and capable of calculating a dynamic pressure and a true airspeed via the Mach number.

The invention belongs to the helicopter atmosphere system field, particularly to an air speed correction method for helicopter maneuvering flight, and solves the problem of air speed change in reverse direction when a helicopter performs large maneuvering movements like changing from rapid downslide to rapid climbing. An inertia sensor on the helicopter measures a vertical acceleration a; the vertical acceleration a opens a mobile points window for low pass filtering processing; the vertical acceleration is corrected after filtering processing to obtain a correction air speed that is close to a real air speed. <{EN3}>The correction of the air speed that is has a local distortion benefits controlling the flight stability by the automatic stationary system, reducing pilot's control burden and improving flight comfort level.

The invention discloses an estimation method of an atmosphere angle of attack and an angle of sideslip in a high-angle-of-attack flight status. Under the premise that the structure of an aircraft is not changed and additional measuring devices and hardware devices are not added, the parameters output by the existing onboard strapdown inertial navigation system, a GPS (Global Position System) system, a flight control system and a fuel measuring system are fully used for resolving the angular acceleration, the rotational inertia, the product of inertia, the coefficient of a moment equation set and the total mass of the aircraft; based on a flight dynamics model, by establishing an extended Kalman filter, and integrating the processes of resolving the flight dynamics model and the status estimation together, accurate estimation of the current angle of attack, the angle of sideslip and the true airspeed is realized, and then the current air speed and the change rate of the air speed are resolved and input into the extended Kalman filter as the feedback information so as to finish the real-time accurate estimation of the angle of attack and the angle of sideslip of next time; the real-time accurate estimation of the angle of attack and the angle of sideslip is realized by a recursive resolving mode, measurement range and measurement precision of an atmosphere data system are improved, and adaptability to complex flight environment is also improved.

The invention discloses a making method of synthetic gas through oxidizing large air-speed part of natural gas, which comprises the following steps: loading nickel nanometer-wire network particle catalyst in the reactor; aerating the composite gas of natural gas and oxygen with the rate of carbon atom number of the natural gas and oxygen molar number at 1. 5-2. 5:1 under 400-900 deg. c at 1X104-5X106h-1 as air speed of the reactor; proceeding partial oxidizing reaction to make the synthetic gas; setting the grain size of the nickel nanometer-wire network particle catalyst at 50-500mum, the aperture of the network hole at 5-30nm, the specific surface area at 9-12m2 / g, the void rate at 90-99%; improving the transmitting rate of methane to 95% and the selectivity of hydrogen and carbon monodioxide to 99% and 98% separately because the nickel nanometer-wire network particle catalyst possesses good reacting activity and stability without loss activity easily; making the manufacturing device with small bulk, reduced pressure, simple structure and high manufacturing ability.

The invention belongs to the helicopter atmosphere system field, particularly to an air speed correction method for helicopter maneuvering flight, and solves the problem of air speed change in reverse direction when a helicopter performs large maneuvering movements like changing from rapid downslide to rapid climbing. An inertia sensor on the helicopter measures a vertical acceleration a; the vertical acceleration a opens a mobile points window for low pass filtering processing; the vertical acceleration is corrected after filtering processing to obtain a correction air speed that is close to a real air speed. <{EN3}>The correction of the air speed that is has a local distortion benefits controlling the flight stability by the automatic stationary system, reducing pilot's control burden and improving flight comfort level.

The embodiment of the present invention provides a system and method for verifying the opening strength of a parachute with infinite mass. The system includes: the airdrop model is connected with the helicopter, and consists of the front cabin and the test parachute; the parachute device includes the test parachute and the main parachute, the test parachute is pre-installed in the test parachute, and the main parachute is pre-installed in the front compartment; the control device includes the on-board Launch control device and on-board recovery control device. The on-board recovery control device includes a pitot tube. The pyrotechnic device is used to complete the release of the airdrop model, and the connection and separation of the test umbrella cabin and the front cabin; the on-board launch control device is used to control the airdrop The release of the model; the recovery control device on the cabin is used to realize the recovery control of the airdrop model; the measuring device is used to measure the flight altitude and true air speed of the airdrop model; the pitot tube is used to measure the parachute opening dynamic pressure of the test parachute. The invention can make the obtained parachute opening load data more accurate, thereby achieving the purpose of verifying the strength of parachute opening conditions with infinite mass.

An aircraft flight recording system and a data processing method thereof relate to the technical field of aircraft and solve the technical problem of monitoring the operating conditions of the aircraft. The system includes a ground communication terminal, a self-contained power supply installed on the aircraft, an airborne satellite communication terminal, and two trigger switches. The first trigger switch is a mechanical micro switch, and the second trigger switch is a bipolar latch. type Hall switch; the airborne satellite communication terminal is connected to the ground communication terminal through the satellite, and the power port of the airborne satellite communication terminal is respectively connected to the airborne power supply and the self-contained power supply through two trigger switches; the first trigger switch is installed at the start of the aircraft In the landing gear compartment, the landing gear triggers its opening and closing. The second trigger switch is set in the real airspeed indicator, and its opening and closing are triggered by two magnets set on the inner wall of the dial; The data is sent to the ground communication terminal in real time. The system and method provided by the invention are beneficial to ground monitoring of aircraft working conditions.