10 results about "Terminal velocity" patented technology

The application relates to an online planning method for a hypersonic variable shape aircraft based on sequence convex optimization and belongs to the field of trajectory planning of a hypersonic variable shape aircraft. The application is realized by the following steps: analyzing the influence of variable shape characteristics on the aerodynamic characteristics of the aircraft, constructing a three-degree-of-freedom dynamics model of the hypersonic variable shape aircraft for trajectory planning; taking the maximum of a weighted function of a terminal height and a terminal speed at the end of a task as a performance index, simultaneously considering initial boundary constraints, terminal boundary constraints and control quantity constraints, combining the aircraft dynamics model to construct an initial trajectory optimization problem of the hypersonic variable shape aircraft; performing convex processing and discretization processing on the trajectory planning problem of the variable length aircraft to obtain a trajectory planning convex problem; constructing a sequence convex optimization solving method based on a variable time domain rolling planning considering multi-stage continuous solving to solve the trajectory planning problem of a gliding section with a terminal time freedom, and realizing online planning of the hypersonic variable shape aircraft according to the solving result.

The application discloses a kind of multi-constraint terminal velocity optimal midcourse guidance methods suitable for long-range glider, including the following steps: launch platform plans the midcourse guidance trajectory of terminal velocity optimization;Launch platform extracts track point from midcourse guidance trajectory, and passes to aircraft;Aircraft generates midcourse guidance instruction according to received track point;According to midcourse guidance instruction, the flight process of aircraft is controlled.The multi-constraint terminal velocity optimal midcourse guidance method suitable for long-range glider provided by the application can meet time, angle and other terminal constraints simultaneously, and ensures that the kinetic energy loss of midcourse guidance section is minimum, and the maximum gliding distance of aircraft is enhanced.

A relative motion control planning method considering terminal velocity constraint comprises the following steps: step one, determining the feasible interval range of control planning transfer time; step two, according to the feasible interval range of control planning transfer time, determining the traversal time interval to obtain the trial point of iterative predictive control planning calculation; step three, according to the obtained trial point, using the method of iterative predictive control planning to traverse all results in the feasible interval range to obtain the terminal state after relative motion control at each trial point; step four, in the series of terminal states obtained in step three, according to the terminal optimization condition, determining one group as the optimal solution. The present application optimizes the optimal control planning position meeting the terminal velocity constraint condition through the iterative predictive comparison in a certain feasible control planning time interval, and calculates the corresponding control planning quantity, which can be applied to various spacecraft on-orbit space rendezvous and docking and other task scenarios.

The present invention discloses a method for designing a curved range-increasing trajectory in the mid-course guidance section, belonging to the field of guidance technology, and is applicable to a simple, highly versatile, and engineering-applicable method for designing a curved range-increasing trajectory of a medium- and long-range anti-tank missile using inertial guidance in the mid-course guidance section. Based on the information output by inertial navigation and combined with target information, this method determines the desired altitude trajectory in the mid-course guidance section. A method for solving the desired altitude trajectory in the mid-course guidance section that takes into account both range increase and terminal velocity requirements is provided. This method is characterized by simplicity, strong versatility, and suitability for engineering applications, and has broad application value in similar medium- and long-range anti-tank missile systems. The present invention has been applied in the development process of a certain domestic missile weapon system.

The invention designs an integrated deformation control method for an aircraft facing dive strike. According to the method, the deformation amount is brought into system control input, a deformation control integrated optimization framework is constructed, and effective execution of a dive strike task is ensured. For an aircraft attitude dynamics model, an intelligent adaptive controller is designed to obtain an expected control moment, and a composite estimation strategy based on a prediction error and a tracking error is established through a parallel estimation model, so that the estimation performance of aerodynamic uncertainty and external interference and the instruction tracking precision are improved. The overdrive control problem caused by input dimension increase is considered, diving speed, deformation and pneumatic control surface deflection limitation are taken as constraint conditions, minimum control torque deviation, aerodynamic resistance and energy loss are taken as optimization objective functions, an optimal distribution model is established, and optimal pneumatic control surface deflection and deformation are solved by adopting a sequential quadratic programming method. According to the method, through integrated coordination of deformation and control, accurate control over the tail end speed and effective tracking of guidance instructions are guaranteed, and technical support is provided for efficient completion of dive attack tasks.

An intelligent CTU rack and an anti-shake control method and apparatus therefor, and a terminal. The method comprises: acquiring a goods placement instruction for controlling the operation of an intelligent CTU rack, and on the basis of the goods placement instruction, controlling a retractable structure to clamp a rack body, wherein the goods placement instruction comprises an initial velocity, a terminal velocity and the maximum acceleration for the operation of the intelligent CTU rack; processing the initial velocity, the terminal velocity and the maximum acceleration, so as to obtain a velocity curve; and on the basis of the velocity curve, controlling the operation speed and operation time of the extension of a fork in the rack body, so as to obtain a goods release instruction when the fork in the rack body is extended in place. In the method, the retractable structure is first controlled, on the basis of the goods placement instruction, to clamp the rack body, so as to stabilize the rack body of the intelligent CTU rack, and then the operation speed and operation time of the extension of the fork in the rack body are controlled by means of the velocity curve, such that the fork in the rack body is extended in place, and thus impact forces generated during the extension and retraction of the fork in the intelligent CTU rack are both reduced.

A device for self-weight material turning and bottom flexible landing comprises a lifting conveying mechanism, an output conveying mechanism, an air gathering cover and an air blowing device, and a belt II of the lifting conveying mechanism is erected on a support III and a support IV higher than the support III. The air gathering cover is of a vertically-through channel structure and is installed on the support IV in the mode that a cantilever is supported above a belt III of the output conveying mechanism, and the air blowing device comprises an air nozzle supplying air to the air gathering cover from the lower portion of the air gathering cover. In the falling process of the frame sectional material, the falling speed of the sectional material can be slowed down through upward lifting buffering force of wind power, the wind can be more gathered through the wind gathering cover, the upward acting force is larger, meanwhile, kinetic energy is saved, cost is reduced, the terminal speed of the frame sectional material is extremely low, and the purpose of soft landing is achieved.

The present invention provides a method, device and system for ultrasonic measurement of a single bubble inside a liquid metal, relating to the technical field of ultrasonic measurement. The method for ultrasonic measurement of a single bubble inside a liquid metal is used for measuring the morphology and velocity of a single bubble in a liquid metal measurement area. Wherein, ultrasonic probes are arranged on both sides along the x-axis, both sides along the y-axis, and both sides along the z-axis of the measurement area; the ultrasonic measurement method includes: obtaining the measurement information of the bubble by the ultrasonic probes during the upward movement of the bubble in the measurement area, the measurement information including the projected lengths of the bubble on the x-axis, y-axis and z-axis, and the angles between the normal lines at each detection point on the bubble surface and the detection directions of the corresponding ultrasonic probes; calculating the morphology parameters and terminal velocity of the bubble according to the measurement information. This ultrasonic measurement method can simultaneously measure the morphology parameters and terminal velocity of the bubble inside the liquid metal, and has a relatively high measurement accuracy.

The invention provides a proportional guidance method based on a neural network. The method comprises the following steps: for the current moment, acquiring position and attitude information of a target and an aircraft; based on the position and attitude information of the target and the aircraft, respectively using a neural network and a proportional guidance law to generate control quantities; performing weighted summation on the control quantity generated by using the neural network and the proportional guidance law to obtain the control quantity required at the current moment; wherein the weighting coefficient is at least related to the height of the aircraft. Compared with an existing proportional guidance method with angle constraint, the method gives consideration to the ballistic end velocity, planning real-time performance and impact angle satisfaction under the condition of considering high dynamic.

The present invention discloses a transverse-longitudinal coupled parameterized guidance method, device, medium, and product based on an analytical solution to an aircraft trajectory, relating to the field of aircraft guidance technology. The present invention obtains an analytical solution to the guidance cycle number, real-time terminal velocity, the motion equation for no-fly zone avoidance, and real-time trajectory planning to determine the nominal profile; determines control instructions based on the real-time motion state data and the nominal profile; assigns control instructions based on the profile tracking guidance law to obtain guidance instructions; corrects the nominal profile based on the analytical solution, and returns to the step of "obtaining the aircraft's real-time motion state data" until the number of corrections to the nominal profile equals the number of guidance cycles. By correcting the nominal profile, the present invention can improve aircraft guidance accuracy.