Abstract: A drilling fluid inhibition evaluation device includes a main test member, a temperature control pressurization system, a gas source, a circulation heating system, a confining pressure pump, a central control system, a computer, an ultrasonic detector and a safety valve electrically connected through pipelines, respectively, the main test member and the temperature control pressurization system sequentially connected with the gas source; the present disclosure can pre-pressurize experimental fluid and then inject the fluid into a dilatometer, so as to prevent the fluid from generating obvious changes of phase states, eliminate pressure setting errors caused by a saturated vapor pressure of the fluid, improve accuracy of evaluation results, inspect a real expansion state of the sample and simultaneously monitor structural change characteristics of a rock sample in real time through reflection conditions of sound waves.

Abstract: A high-temperature and high-pressure drilling fluid inhibition evaluation device includes a main test member, a temperature control pressurization system, a gas source, a circulation heating system, a confining pressure pump, a central control system, a computer, an ultrasonic detector and a safety valve electrically connected through pipelines, respectively, the main test member and the temperature control pressurization system sequentially connected with the gas source; the present disclosure can pre-pressurize experimental fluid and then inject the fluid into a dilatometer, so as to prevent the fluid from generating obvious changes of phase states, eliminate pressure setting errors caused by a saturated vapor pressure of the fluid, improve accuracy of evaluation results, inspect a real expansion state of the sample and simultaneously monitor structural change characteristics of a rock sample in real time through reflection conditions of sound waves.

Abstract: A method for determining the heading of an unmanned aerial vehicle and an unmanned aerial vehicle are provided. The method includes: acquiring a first heading angle of an unmanned aerial vehicle by means of a first sensing system, and acquiring a second heading angle of the unmanned aerial vehicle by means of a second sensing system (S102); judging whether the second heading angle is valid according to a comparing result (S104); and if the second heading angle is invalid, determining the first heading angle as a current heading angle of the unmanned aerial vehicle (S106).

Abstract: An unmanned aerial vehicle control method and apparatus are provided. The method includes: obtaining, in real time, the motion status information of an unmanned aerial vehicle moving under the effect of a user-applied external force (100); generating at least one unmanned aerial vehicle control instruction based on the motion status information (110) and controlling the unmanned aerial vehicle to perform a corresponding flight action according to the at least one unmanned aerial vehicle control instruction (120). After an unmanned aerial vehicle moves under the effect of a user-applied external force, the control method further controls the unmanned aerial vehicle to perform a corresponding flight action according to the current motion tendency of the unmanned aerial vehicle, thus freeing the user from mastering a complicated unmanned aerial vehicle control technology, reducing the difficulty of the control over the unmanned aerial vehicle and making the unmanned aerial vehicle more applicable.

Abstract: The invention relates to a pressure oscillation simulation device of deep coalbed methane and a method thereof. The device includes: a box, a liquid discharge pipe arranged on a bottom portion of the box, a gas source connected to the box through a gas injection pipe, a water source connected to the box through a drainpipe that includes a branch pipe; a measuring system including a pressure measuring member and a liquidometer. The present disclosure can simulate the coalbed pressure oscillation in a coalbed gas exploitation process and be of simple structure and high reliability, and can simulate influences of the pressure oscillation on a wellbore and a stratum environment in the coalbed exploitation process to provide reliable data support for an actual coalbed exploitation; the simulation method of the present disclosure can accurately simulate the pressure oscillation of the wellbore and the stratum.

Abstract: A method and device for flight height adjustment and flight control of an unmanned aerial vehicle. The flight height adjustment method comprises: obtaining a planned flight height of an unmanned aerial vehicle at each flight position point; and adjusting the planned flight heights at the flight position points until the difference between the adjusted flight heights at any two adjacent flight position points is less than or equal to a preset value.

Abstract: An unmanned aerial vehicle control method and apparatus are provided. The method includes: obtaining, in real time, the motion status information of an unmanned aerial vehicle moving under the effect of a user-applied external force (100); generating at least one unmanned aerial vehicle control instruction based on the motion status information (110) and controlling the unmanned aerial vehicle to perform a corresponding flight action according to the at least one unmanned aerial vehicle control instruction (120). After an unmanned aerial vehicle moves under the effect of a user-applied external force, the control method further controls the unmanned aerial vehicle to perform a corresponding flight action according to the current motion tendency of the unmanned aerial vehicle, thus freeing the user from mastering a complicated unmanned aerial vehicle control technology, reducing the difficulty of the control over the unmanned aerial vehicle and making the unmanned aerial vehicle more applicable.

Abstract: The embodiment of the disclosure relates to an Unmanned Aerial Vehicle (UAV) terrain simulation flying method and device, and a UAV. The method includes: acquiring a vertical distance between a UAV and the ground; acquiring an oblique distance between the UAV and the ground; acquiring an angle between the vertical distance and the oblique distance; and adjusting a terrain simulation flying state of the UAV according to the angle, the vertical distance and the oblique distance.

Abstract: A method for determining the heading of an unmanned aerial vehicle and an unmanned aerial vehicle are provided. The method includes: acquiring a first heading angle of an unmanned aerial vehicle by means of a first sensing system, and acquiring a second heading angle of the unmanned aerial vehicle by means of a second sensing system (S102); judging whether the second heading angle is valid according to a comparing result (S104); and if the second heading angle is invalid, determining the first heading angle as a current heading angle of the unmanned aerial vehicle (S106).

Abstract: A method for filtering in ranging of a UAV is provided, which is based on a characteristic that velocities of the UAV change continuously during a moving process. A current velocity of the UAV is obtained via seeking difference of distances measured by the sensor, then a variance of continuous velocities is calculated and it is determined whether a current distance is valid according to the variance. The general process of the method is as follows. First, initial distances measured by the sonar sensor are acquired, secondly, it is determined whether a new distance is valid according to the initial distances, if the new distance satisfies a curtain condition, the new distance is considered to be valid and the initial distances are updated; if the new distance does not satisfy the curtain condition, a distance is estimated and used as the current distance and the initial distances are maintained.

Abstract: A rotorcraft and an automatic landing system and method thereof are provided in the present disclosure. The automatic landing system of the rotorcraft includes a controller, a laser emitter, a camera, an electronic governor and a motor configured to drive a propeller of the rotorcraft to rotate. The laser emitter and the camera are both locate in a bottom portion of an airframe of the rotorcraft. The laser emitter has two emission heads, laser beams emitted from the two emission heads respectively are symmetrical about a central axis, the central axis is perpendicular to a horizontal plane of a ground, and an angle between each laser beam and the central axis is an acute angle. Simply with an operation of the laser emitter, the camera and the controller, the flight speed and displacement of the rotorcraft can be controlled to realize automatic landing in the present disclosure.

Abstract: The embodiment of the disclosure relates to an Unmanned Aerial Vehicle (UAV) terrain simulation flying method and device, and a UAV. The method includes: acquiring a vertical distance between a UAV and the ground; acquiring an oblique distance between the UAV and the ground; acquiring an angle between the vertical distance and the oblique distance; and adjusting a terrain simulation flying state of the UAV according to the angle, the vertical distance and the oblique distance.

Abstract: A method and an apparatus for obtaining a range image, and a UAV are provided. The method includes: reading an image sequence of a predetermined scene, in which the Nth image and the (N+1)th image of the image sequence have an overlapping region; obtaining a pixel movement velocity of each pixel point in the overlapped region in a camera coordinate system of the UAV; obtaining an actual flying velocity of the UAV in a world coordinate system; obtaining a range image of each overlapped region according to the pixel movement velocity of each pixel point in the overlapped region in the camera coordinate system of the UAV, the actual flying velocity of the UAV in the word coordinate system, and parameters of the airborne camera, and obtaining a range image of the preset scene through integrating the range image of each overlapped region.

Abstract: A method and an apparatus for obtaining a range image, and a UAV are provided. The method includes: reading an image sequence of a predetermined scene, in which the Nth image and the (N+1)th image of the image sequence have an overlapping region; obtaining a pixel movement velocity of each pixel point in the overlapped region in a camera coordinate system of the UAV; obtaining an actual flying velocity of the UAV in a world coordinate system; obtaining a range image of each overlapped region according to the pixel movement velocity of each pixel point in the overlapped region in the camera coordinate system of the UAV, the actual flying velocity of the UAV in the word coordinate system, and parameters of the airborne camera, and obtaining a range image of the preset scene through integrating the range image of each overlapped region.

Abstract: A method for filtering in ranging of a UAV is provided, which is based on a characteristic that velocities of the UAV change continuously during a moving process. A current velocity of the UAV is obtained via seeking difference of distances measured by the sensor, then a variance of continuous velocities is calculated and it is determined whether a current distance is valid according to the variance. The general process of the method is as follows. First, initial distances measured by the sonar sensor are acquired, secondly, it is determined whether a new distance is valid according to the initial distances, if the new distance satisfies a curtain condition, the new distance is considered to be valid and the initial distances are updated; if the new distance does not satisfy the curtain condition, a distance is estimated and used as the current distance and the initial distances are maintained.

Abstract: A rotorcraft and an automatic landing system and method thereof are provided in the present disclosure. The automatic landing system of the rotorcraft includes a controller, a laser emitter, a camera, an electronic governor and a motor configured to drive a propeller of the rotorcraft to rotate. The laser emitter and the camera are both locate in a bottom portion of an airframe of the rotorcraft. The laser emitter has two emission heads, laser beams emitted from the two emission heads respectively are symmetrical about a central axis, the central axis is perpendicular to a horizontal plane of a ground, and an angle between each laser beam and the central axis is an acute angle. Simply with an operation of the laser emitter, the camera and the controller, the flight speed and displacement of the rotorcraft can be controlled to realize automatic landing in the present disclosure.