56 results about "Pressure altitude" patented technology

The invention relates to high integrity MIMU / GPS / micro magnetic compass / pressure altitude gage integrated navigation system. It is made up MIMU subsystem, GPS subsystem, micro magnetic compass subsystem, pressure altitude gage subsystem, and integrated navigation computer used to process subsystem output data and inosculate information to output carrier position, speed, and attitude information. The four subsystems adopt hard ware integrative high grade integration technique. The navigation computer adopts three embedding type microprocessor and has the feature of redundancy multiplexing. The GPS, micro magnetic compass, pressure altitude gage use one microprocessor together to process their algorithm. Navigation algorithm is made up of strap down inertial navigation algorithm, multi velocity model combined filtering algorithm. The invention has the advantages of small volume, low cost, high reliability, fast response speed and high precision. Thus it can be used in micro-miniature flyer precise navigation.

A cabin pressure altitude monitor and warning system provides a warning when a detected cabin pressure altitude has reached a predetermined level. The system is preferably embodied in a portable, pager-sized device that can be carried or worn by an individual. A microprocessor calculates the pressure altitude from signals generated by a calibrated pressure transducer and a temperature sensor that compensates for temperature variations in the signals generated by the pressure transducer. The microprocessor is programmed to generate a warning or alarm if a cabin pressure altitude exceeding a predetermined threshold is detected. Preferably, the microprocessor generates two different types of warning or alarm outputs, a first early warning or alert when a first pressure altitude is exceeded, and a second more serious alarm condition when either a second, higher pressure altitude is exceeded, or when the first pressure altitude has been exceeded for a predetermined period of time. Multiple types of alarm condition indicators are preferably provided, including visual, audible and tactile. The system is also preferably designed to detect gas concentrations and other ambient conditions, and thus incorporates other sensors, such as oxygen, relative humidity, carbon dioxide, carbon monoxide and ammonia sensors, to provide a more complete characterization and monitoring of the local environment.

The invention provides an aviation emergency instrument which comprises an atmospheric pressure measurement unit, an inertial measurement unit, a double-antenna GPS satellite receiver connected with a satellite signal receiving antenna, a graphic display unit, a secondary power supply circuit, and a comprehensive processing and calculation unit, wherein the comprehensive processing and calculation unit receives the information from the individual sensors, calculates the navigation parameters indicative of air speed, pressure altitude, posture, flight direction, longitude and latitude by use of a sensor information fusion algorithm, and sends the calculation result to the high-density liquid crystal graphic display unit. According to the invention, since the aviation emergency instrument can provide the navigation parameters indicative of air speed, pressure altitude, posture (pitch angle and roll angle), flight direction, longitude and latitude, the aviation emergency instrument can not only provide reference information to a pilot who operates the main flight instrument in the normal state but also serve as an emergency instrument in case that the main flight instrument is in the failure state. When the main flight instrument completely fails to work, the pilot can operate the aircraft to return safely by means of the navigation information provided by the emergency instrument.

The invention relates to a road segment traffic index estimation system based on unmanned aerial vehicle measurement. The estimation system is arranged on an unmanned aerial vehicle and comprises an aerial camera, an image processor, a pressure altitude sensor and a main controller, the aerial camera is connected with the image processor, shot road segment images are sent to the image processor to be processed, the main controller is respectively connected with the image processor and the pressure altitude sensor, and a road segment traffic index is estimated according to the image processing result of the image processor and the altitude, detected by the pressure altitude sensor, of the unmanned aerial vehicle. By means of the road segment traffic index estimation system, traffic crowdedness information of key road segments can be provided for road traffic management departments, data are more visual and more accurate, and the road traffic management departments can conveniently develop accurate and effective traffic processing measures.

The invention discloses a low-altitude flight control method applied to airborne geophysical prospecting of an unmanned aerial vehicle. The low-altitude flight control method includes adopting complementary filter of pressure altitude and radio altitude of the unmanned aerial vehicle to obtain altitude signals with high signal to noise ratio as a low-altitude flight height control source of the unmanned aerial vehicle. High-frequency topographic influence can be filtered by flight altitude, terrain can be well tracked, and airborne geophysical prospecting flight operation can be realized effectively in hills and small-gradient mountainous areas, so that the unmanned aerial vehicle can fly at minimum altitude along topographic relief, track the terrain and effectively avoid obstacles and is capable of acquiring high-quality exploration data of an airborne geophysical prospecting operation aeromagnetic system and an airborne radioactive system, and geophysical prospecting safety is improved. Feasibility of the low-altitude flight control method is verified by practical tests, is completely succeeded and has pilot application effect for relevant flight control methods and creates basis for massive airborne geophysical prospecting application in the unmanned aerial vehicle.

The invention discloses a determination method for pressure altitude parameters on a subsonic vehicle body. The determination method comprises a selection principle of a pressure source on the subsonic vehicle body and a data processing method for measuring pressure based on a selected pressure source, wherein the selection principle of the pressure source on the subsonic vehicle body is used for selecting and locating the pressure source; the data processing method for measuring pressure based on the selected pressure source comprises a correction formula fitting and measured value returning and calculating method, wherein the correction formula comprises [alpha] correction, [beta] correction and static pressure correction, and the returning and calculating method is a method that objective variables are obtained according to the iteration of pressure measuring values. Test results show that the corrected data has very high reducibility, the objective variables including a flying attitude angle, a speed and the like of a subsonic vehicle with higher precision can be obtained by combining the returning and calculating method, therefore, a new method is provided for the subsonic flying speed measurement of the subsonic vehicle.

A system for determining the difference in altitude between a vehicle and a portable electronic device is provided. The system comprises a first pressure sensor, a second pressure sensor, and a processor. The first pressure sensor is coupled to the portable electronic device and generates a first signal indicative of the atmospheric pressure at the portable electronic device. The second pressure sensor is coupled to the vehicle and generates a second signal indicative of the atmospheric pressure at the vehicle. The processor is coupled between the vehicle and the portable electronic device and is configured to receive the first signal and determine a first pressure altitude therefrom, and receive the second signal and determine a second pressure altitude therefrom.

The invention discloses an inertia altitude channel damping Kalman filtering method based on atmosphere assistance. The method comprises the following steps that firstly, an atmosphere data system pressure altitude error model in the moving process of an unmanned helicopter is established; then, based on the pressure altitude error model and a traditional inertia / atmosphere damping loop, a state equation and a measuring equation of a six-state damping Kalman filter including pressure altitude errors of an atmosphere data system and sensor errors of an inertia navigation system are established; finally, inertia / atmosphere navigation system damping Kalman filtering is carried out on the altitude error and the vertical speed error generated in the flying process of the unmanned helicopter, and a combined navigation system navigation result obtained after damping Kalman filtering is obtained. By means of the inertia altitude channel damping Kalman filtering method based on atmosphere assistance, tracking and compensation for atmosphere altitude measuring errors can be achieved in the flying process of the unmanned helicopter so as to improve the altitude precision in the atmosphere-assisted inertia navigation altitude channel, and the method is suitable for engineering application.

The invention discloses a course reversal method for safety protection of fuel quantity of an unmanned aerial vehicle. The method comprises the following steps: setting an initial oil capacity in software of a flight control computer; setting a real-time residual fuel capacity calculating function according to a test relationship table of oil consumption of an engine, an accelerator and a pressure altitude; then combining the function with the existing GPS position and preset air route longitude and latitude information of the unmanned aerial vehicle to estimate the requested safe fuel quantity of the unmanned aerial vehicle which can continuously land to an airport along an air route and return to the airport along the air route; when a safety threshold value is achieved, automatically shielding an operator of the unmanned aerial vehicle by the flight control computer to implement the instruction for online air route adjustment and executing an emergent return task of the unmanned aerial vehicle which continuously flies to the airport along the preset air route or returns along the air route for safety protection of fuel quantity.

The invention belongs to the electromechanical control technology of aviation emergency escapement instruments, and relates to a reserve parachute opening control device. The reserve parachute control device comprises a pressure sensor, a controller and a cutting device, wherein the pressure sensor, the controller and the cutting device are sequentially connected in series through cables. The pressure sensor can feel the change of atmospheric pressure, convert the pressure value into an electrical signal and transmit the electrical signal to the controller. The controller can receive the pressure value electrical signal transmitted by the pressure sensor, calculate the pressure altitude and the falling speed of a parachute, and output a control signal to the cutting device. The cutting device is connected with a contraction rope of a reserve parachute and used for cutting off the contraction rope when receiving the control signal. The reserve parachute opening control device can judge whether the main parachute is opened or not according to the pressure altitude and the falling speed of the parachute, and automatically open the reserve parachute when the main parachute is not opened, and therefore casualties caused when the parachute manual opening can not be achieved can be avoided.

The invention provides an unmanned plane pressure altitude change rate measurement system. The system comprises an atmosphere static pressure transducer, a temperature transducer, a signal processing circuit, an A / D converter and a micro controller unit; an acquired atmospheric pressure signal and an acquired temperature value signal are transmitted to the signal processing circuit through the atmosphere static pressure transducer and the temperature transducer arranged on an unmanned plane, a signal processed by the signal processing circuit is transmitted to the A / D converter, and a signal through the AD conversion is sent to the micro controller unit; the uncorrected pressure altitude change rate is fast resolved by using linear interpolation, and is corrected by using a software compensating method so as to obtain the final pressure altitude change rate. The atmosphere static pressure transducer is used for measuring the atmosphere static pressure change rate to obtain the value of the pressure altitude change rate, the measurement speed of the system is increased, the measurement precision of the system and the accuracy of the unmanned plane pressure altitude change rate are obviously improved; meanwhile the security of the unmanned plane is improved.

The invention provides a quadrotor. The quadrotor comprises a quadrotor body, wherein a supporting frame is arranged on the quadrotor body; four cross-shaped mechanical arms are arranged on the supporting frame; a propeller is arranged at the end part of each mechanical arm; a driving motor drives the corresponding propeller to rotate; an ultrasonic sensor is arranged at the top of a propeller shaft of each propeller; a pressure altitude sensor is arranged on the surface, facing the ground, of the supporting frame; a control box is arranged on the quadrotor body; a chip of an integrated controller is arranged in the control box; a protruding end is also arranged on the supporting frame; an industrial camera is arranged on the protruding end. According to the quadrotor provided by the invention, detection and patrol of cracks on a bridge can be realized automatically, so that lots of manpower and material resources can be saved; the measurement is convenient, the manufacturing cost of the quadrotor is low, and the measurement efficiency is high.

A flight control system for a helicopter having a main rotor and a tail rotor is provided. The flight control system includes an automatic rotor speed control being configured to transition the main rotor and the tail rotor between a high speed and a low speed based upon a plurality of received information without requiring any pilot action, the plurality of received information comprising height above ground level, knot indicated air speed, outside air temperature, barometric altitude, pressure altitude, density altitude, and an engine operational status.

The invention discloses a multi-degree of freedom inertial sensor four-axis unmanned aerial vehicle autonomous navigation flight controller, which comprises a DSP arranged inside the unmanned aerial vehicle. A power supply module provides power for the DSP; the DSP is directly connected with the inertial sensor and an air pressure altitude sensor via a system bus to integrate the inertial sensor and the air pressure altitude sensor as a whole; the DSP is also connected with a wireless data transmission radio station and can communicate wirelessly with a ground station control system via the wireless data transmission radio station; the information output end of the DSP is connected with an electron speed regulator; and the electron speed regulator is connected with the motor of the unmanned aerial vehicle and can control the speed of the motor of the unmanned aerial vehicle. The multi-degree of freedom inertial sensor four-axis unmanned aerial vehicle autonomous navigation flight controller has the advantages that the processor is integrated with the inertial navigation sensor and an air data sensor and can perform data exchange; and due to the integrated design, the system-level serial communication is reduced, the inertial data updating rate is improved, the reliability of the system is enhanced, and the cost, the volume, the weight and the power consumption are reduced.

A system for identifying human motion of a subject may comprise: a sensor platform attached to the subject; an attitude filter that receives sensor data and calculates the attitude and heading of the platform; a feature construction and aggregation unit that receives the sensor data and the attitude and heading to calculate a feature vector for a human motion model, an evaluation unit that receives feature vectors and calculates the probability that an instance of a specific human motion occurred; wherein the feature vector comprises: one or more feature constructions, X, such as: forces along and perpendicular to the gravity field direction; a magnitude of rotations perpendicular to the gravity field direction; an adjusted pressure altitude; one or more feature constructions which are time derivatives dX / dt; and one or more feature constructions which are derivatives V(dX / dt), wherein: V(x)=2*H(x)−1, H(x)=+1 (x>0), 0 (x<0), and x is dX / dt.

The invention discloses a general aviation onboard monitoring system. The general aviation onboard monitoring system comprises a pressure altitude measurement module, a positioning module, a Beidou processing unit, a central processing unit and a battery module, wherein the pressure altitude measurement module is used for measuring the pressure altitude information of a general aircraft, and sending the pressure altitude information to the central processing unit, the positioning module is used for providing the positioning information of the general aircraft in real time, and sending the positioning information to the central processing unit, the Beidou processing unit is connected with a Beidou antenna, and is used for receiving and dispatching communication by utilizing Beidou satellites, the Beidou processing unit is used for processing received external command information, sending the processed command information to the central processing unit, and sending the processed positioning information obtained from the central processing unit by the Beidou antenna, the central processing unit is used for processing positioning information required for each module, and managing the running condition of whole onboard monitoring system, and the battery module is used for providing a power supply. With the adoption of the general aviation onboard monitoring system, the monitoring capability of the general aircraft can be effectively improved, and a feasible and effective monitoring means can be provided for a general aircraft owner and a low-altitude airspace manager.

The invention relates to a method for measuring the deviation rate of an airplane relative to a side direction of a runway, and belongs to the technical field of avionics display control. The method comprises the steps: firstly collecting the glide deviation of the airplane relative to a standard glide slope, the pressure altitude and ground velocity of the airplane relative to the runway, the length of the runway and a set glide slope angle, and solving the distance between the airplane and a heading beacon station according to the above collected information; secondly solving the acceleration of the airplane in a side direction of the runway according to a roll angle, a pitch angle, a yaw angle, a selected course, and the X-axis, Y-axis and Z-axis accelerations of an airplane body coordinate system; finally obtaining the deviation rate of the airplane relative to the side direction of the runway through employing a complementary filtering algorithm. According to the invention, the method inhibits the high-frequency noise in heading beacon data and the low-frequency noise in inertia data while making the comprehensive use of the heading beacon data and inertia data, is higher in precision of output data, and can support a head-up flight guide function.

The invention discloses a tumble detection system. The system comprises an air pressure sensor, a six-axis sensor, a photoelectric type pulse sensor, a main control unit (MCU), a server and a mobile terminal, wherein the air pressure sensor is used for acquiring air pressure altitude data of a sporter; the six-axis sensor is used for acquiring accelerated speed data and angular speed data generated by the sporter; the photoelectric type pulse sensor is used for acquiring user pulse data; the MCU is used for performing feature processing on the acquired air pressure altitude data, the accelerated speed data, the angular speed data and the user pulse data to acquire feature data, judging whether the feature data is tumble data or not, and generating tumble information if the feature data is the tumble data and transmitting the tumble information to the server through the GPRS module; the MCU comprises the GPRS module; the server is used for transmitting the tumble information to the mobile terminal; and the mobile terminal is used for receiving the tumble information transmitted by the server side and displaying the tumble information. The system can improve the detection accuracy.

The invention relates to a road segment traffic index estimation system based on unmanned aerial vehicle measurement. The estimation system is arranged on an unmanned aerial vehicle and comprises an aerial camera, an image processor, a pressure altitude sensor and a main controller, the aerial camera is connected with the image processor, shot road segment images are sent to the image processor to be processed, the main controller is respectively connected with the image processor and the pressure altitude sensor, and a road segment traffic index is estimated according to the image processing result of the image processor and the altitude, detected by the pressure altitude sensor, of the unmanned aerial vehicle. By means of the road segment traffic index estimation system, traffic crowdedness information of key road segments can be provided for road traffic management departments, data are more visual and more accurate, and the road traffic management departments can conveniently develop accurate and effective traffic processing measures.

The invention relates to a pressure altitude simulator and belongs to the technical field of structure design of pressure altitude simulators. A static port, a total port and plug-in holes are formed in the outer end of a simulator body. A pump assembly, a liquid crystal display module, a sensor assembly, a power source assembly, a volume assembly and a deflation valve assembly are arranged inside the simulator body. A fixing plate is further arranged inside the simulator body, and a several-piece assembly and a valve assembly are arranged on the fixing plate. Under the condition that the function and performance of equipment are not damaged, the functions of all units inside the pressure altitude simulator and the structure of the pressure altitude simulator are reasonably adjusted, so that the equipment is reduced to 4U at present from original 8U, and the miniaturization design of the pressure altitude simulator is achieved; meanwhile, due to the fact that functional modules of the simulator are integrated and the structure is simpler after adjustment, production and maintenance cost is correspondingly reduced, and the demands of users for miniaturization and low cost of test equipment are met.

A computer system 20 provided in an aircraft 1 includes, as a module of a computer program to be executed, an approach determination section 31 configured to determine whether the aircraft 1 is approaching a landing site. The approach determination section 31 includes, as a condition for determination of approaching, establishment (C1) of one or both of a condition (C11) that a first absolute altitude A1 obtained by an radio altimeter 21 mounted on the aircraft 1 is low relative to a first approach altitude AA1, and a condition (C12) that a second absolute altitude A2 that is obtained by subtracting an altitude AL of the landing site from a pressure altitude Ap determined by a barometric altimeter 22 mounted on the aircraft 1 is low relative to a predetermined second approach altitude AA2.

An aircraft includes a fuselage having a cabin. The aircraft also includes a cabin pressure sensor configured to detect cabin pressure level of the cabin. The aircraft further includes a controller configured to determine a pressure threshold as a function of a pressure altitude of a destination airport of the aircraft. The controller is also configured to activate a flight safety system based on the cabin pressure level satisfying the pressure threshold.

The invention discloses health detection equipment and method for a hectometer-level water diversion vertical shaft of a large-sized hydropower station. The equipment comprises an unmanned airship, adata acquisition device and a winch, wherein the data acquisition device is suspended below the unmanned airship through multiple nylon ropes; the bottom of the data acquisition device is connected with the winch; the data acquisition device is of a 4-layer structure, and comprises a shock absorption spring arranged on the top layer, a laser scanner, a pressure altitude sensor and an inert measurement device which are arranged on the second layer, a lighting device and a camera which are arranged on the third layer, and a control device arranged on the bottom layer; a defective position and adefect shape of the inner wall of the water diversion vertical shaft are obtained by processing various acquired data. The health detection equipment breaks through the problems in implementation of manual detection and high detection difficulty for the water diversion vertical shaft of the large-sized hydropower station, fills the international blank of informatization detection of a hectometer-level vertical shaft section, and solves the technical problems on determination of the defective position and measurement of the defect shape of the inner wall of the water diversion vertical shaft section.

The invention relates to an air pressure altitude detection apparatus, which comprises a programmable controller, a computer, a sensor set and a low pressure cabin. According to the present invention, the single sensor in the prior art is changed into the sensor set comprising a plurality of sensors, such that the problem that the precision can not achieve requirements when the air pressure altitude exceeds 10000 meters is effectively solved.

The invention discloses a vehicle-mounted inertial navigation system. The vehicle-mounted inertial navigation system comprises a pressure altitude sensor, a milemeter, an acceleration sensor, an image acquisition module, a control module, a touch display module, an audio module and a communication module, wherein a plurality of interrupt response modules, an I2C bus interface module, a serial port communication interface module and a data input-output module are arranged inside the control module; the milemeter is connected with the interrupt response modules of the control module; the pressure altitude sensor is connected with the control module by virtue of the I2C bus interface module; the communication module is connected with the control module by virtue of the serial port communication interface module; and the acceleration sensor, the image acquisition module, the touch display module and the audio module are connected with the control module by virtue of the data input-output module. The vehicle-mounted inertial navigation system is capable of providing three-dimensional position, speed and track data and has the assistance of the characteristics of driver eye-closing caution, impact caution, border crossing caution, automatic cooperation of near interest points, and the like.

The invention relates to an indoor and outdoor integrated combined positioning device and belongs to the technical field of positioning. With the indoor and outdoor integrated combined positioning device adopted, full-airspace coverage position information service can be provided for people. The indoor and outdoor integrated combined positioning device comprises a data acquisition module and a combined positioning module; the data acquisition module is used for acquiring magnetic field data, angular velocity data, acceleration data, wireless signal data, an air pressure altitude data magnetic field and satellite navigation data; and the combined positioning module is connected with the data acquisition module and is used for receiving the data acquired by the data acquisition module, judging whether a current positioning condition is in a room or not, and performing the positioning solving of people through inertial navigation positioning, magnetic field matching positioning, wireless positioning, air pressure altitude measurement and map constraint on the basis of a particle filter framework if the current positioning condition is in a room, and performing the positioning solving of the people through a combined positioning method including satellite positioning. With the system of the invention adopted, full-airspace coverage position information service can be provided for the people. The system is used for emergency rescue, safety management, positioning navigation and other scenes.

The invention relates to a system and method for correcting the reference value of pressure conversion altitude. The system is used in a navigational aid and comprises a storage unit, a judgment unit, a sensing unit and a computing unit, the storage unit is used for storing contour line geographic information; the judgment unit is used for judging whether the geographic position information positioned by the navigational aid is on the contour lines; the sensing unit is used for measuring the atmospheric pressure around the navigational aid and obtaining an atmospheric pressure value; and the computing unit is used for computing a reference value according to the contour line information and the atmospheric pressure value, and carrying out conversion computation among the contour line information, atmospheric pressure value and reference value. By using the system and method, a user does not need to mind the problem of setting of the reference value, and the GPS device can automatically correct the conversion reference value of the pressure altitude at any time and enable the altimeter to always keep high measurement accuracy, thereby saving trouble for the user and facilitating applications of the user.

The invention relates to the technical field of vehicle-mounted systems and provides a vehicle-mounted inertial navigation system to overcome the technical problem of poor navigation experience of conventional vehicle-mounted navigation systems. The vehicle-mounted inertial navigation system comprises a data acquisition module, a data processing module and a data output module, wherein the data acquisition module comprises a pressure altitude sensor, an acceleration sensor, an image acquisition module and a mileometer; the data processing module comprises a one-chip microcomputer, a signal processing unit, a USB interface, an interruption response module, an I2C bus interface module and a serial port communication interface module; the one-chip microcomputer is connected with the signal processing unit; the signal processing unit is connected with the USB interface; the data output module comprises a communication module and a display module; the pressure altitude sensor is connected with the I2C bus interface module; the acquisition module and the data processing module are connected with the data output module through data lines via the USB interface; the mileometer is connected with the interruption response module; and the communication module and the display module are connected with the serial port communication interface module. Thus, navigation experience of three-dimensional location is provided.

The invention provides methods and systems for determining airspeed of an aircraft. The methods and systems allow for calculation of airspeed in near-ground and on-ground aircraft operation. A GPS altitude and a vertical acceleration of the aircraft are obtained for a current time frame. A geometric altitude for the previous time frame is determined, and the difference between the GPS altitude andgeometric altitude are combined with the vertical acceleration to calculate a geometric altitude rate of change. The geometric altitude rate of change is used to calculate a pressure altitude rate ofchange, which is used to calculate a pressure altitude for the aircraft. A static pressure is calculated from the pressure altitude, and the airspeed is calculated using the static pressure.