61 results about "Pitch angle" patented technology

A system and device for detecting yaw and changes in pitch angle for use with navigational and positional devices. The system and device include a multi-axis magnetic field sensing device and a controller. Preferably, the magnetic field sensing device is a multi-axis magnetic compass that is capable of sensing variations in pitch and yaw. The controller is adapted to process yaw and pitch rotational data to determine a positive or a negative change in pitch.

In one embodiment and method of the present invention, an optical interference fly height (FH) test apparatus for measuring FH is disclosed, in accordance with an embodiment of the present invention, to include a slider, a transparent disk, means for directing a light beam directed between the slider and the disk, and means for iteratively measuring an estimated FH using at least two points of measurement on the slider when the slider is moved away from the disk at a pitch angle, wherein the estimated FH is computed as a function of the pitch angle and during each iteration, a previously-estimated FH is used to converge the estimated FH so that the estimated FH is within a predetermined range from the actual FH.

The present invention provides an attitude fusion enhanced measurement method and system based on inertial navigation technology. The method includes step 1, acquiring attitude data detected by each sensor, and performing data initialization; step 2, performing strapdown calculation on the initialized attitude data; Step 3, correct the attitude data corresponding to each sensor; Step 4, use feedback control to correct the gyro zero point according to the corrected acceleration data and magnetometer data; Step 5, output the corrected attitude data. The invention has a magnetic anomaly detection function, and the magnetic correction does not affect the pitch angle and roll angle correction; based on the nonlinear theory, better convergence speed and control precision are provided.

The invention discloses a space-borne real-time occultation prediction method, which comprises first obtaining the position velocity of the spacecraft according to the positioning equipment of the occultation detector, and calculating the orbital parameters of the spacecraft; and then calculating the orbital parameters of the spacecraft and all navigation stars after 10s position, and calculate the pitch angle, azimuth angle, tangent point height and antenna azimuth angle of all navigation stars, and judge whether the obtained pitch angle Elv, tangent point height Hight and antenna azimuth angle meet the threshold of occultation events, if satisfied , then extrapolate the time for 30s and 1min, and repeat the above calculation and judgment process respectively. If all are satisfied, it is determined that the navigation star is an occultation. The present invention judges occultation events by adopting continuous arc segments by inertial navigation equipment, thereby enhancing the accuracy of forecast results, the method is simple and easy, and has important application value for real-time forecast.

The invention discloses a multi-parameter alternating search-based metrewave radar low elevation height measurement method, mainly solves the problem that the error in the height measurement of up and down positions in the prior art is large. The method comprises the following implementation steps: extracting a target signal from a radar echo to obtain a covariance matrix of the target signal; calculating a synthesis steering vector by using a direct steering vector and a reflected steering vector; estimating the pitch angle of a direct wave to obtain an estimated value; estimating the pitch value of a reflected wave to obtain an estimated value; performing alternating search on a ground reflection coefficient magnitude, a ground reflection coefficient phase, the pitch angle of the direct wave and the pitch angle of the reflected wave to obtain the estimated values of each parameter; judging whether the alternating search is finished or not; searching the pitch angle of the direct wave to obtain the estimated value of the pitch angle of the direct wave, namely the precise elevation of a target; and obtaining the target height. The method does not depend on precise radar position altitude parameters; the adaptive capacity of radar to the position is enhanced; the height measurement precision is improved; and the method can be used for target positioning and tracking.

The invention discloses an attitude measuring method and device. First obtain the pitch angle, roll angle, geomagnetic three-component and angle change, and then calculate the attitude quaternion by solving the pitch angle, roll angle, and geomagnetic three-component, and then filter the attitude quaternion and angle change to obtain The quaternion output data; finally, the angle transformation is performed on the quaternion output data to obtain the attitude result. The invention compensates the obtained three components of pitch angle, roll angle and geomagnetism through the obtained angle variation, avoids magnetic interference and high-frequency shaking, improves measurement accuracy and realizes dynamic measurement.