8 results about "Helicopter dynamics" patented technology

The present application belongs to the technical field of helicopter dynamics test, and relates to a method and system for measuring the distance between blades of upper and lower rotors based on measured bending moment. The measured bending moment data in flight is used, and the existing blade measurement system is used. Without additional measurement equipment, the relationship between bending moment and deformation is used to establish the calibration relationship between the test bending moment and the deformation of different profiles of the blade, so as to obtain the distance between the blades of the upper and lower rotors in the real-time flight state. The method can relatively real-time monitor the distance between the blades of the upper and lower rotors in the full flight spectrum state without additional measurement equipment, and ensure flight safety. The method has the advantages of simplifying the measurement method of the blade tip distance, shorter feedback time compared with the light ray sensor and radar wave measurement, and better real-time effect.

The application discloses a helicopter low-altitude flight path planning method based on motion state search and enhanced safety pipeline, which comprises the following steps: firstly, based on a grid map, segmented flight path planning is carried out to generate a helicopter motion state space considering dynamic constraints and maneuvering characteristics; then, after the state space is expanded and a cost function is established, an optimal path search is carried out in the expanded state space by using an improved hybrid A* algorithm; then, in a local map which is updated in real time according to dynamic threats, an enhanced safety pipeline is generated by expanding, pruning and interpolating based on the initial flight path according to the safety constraints of the flight path; finally, the B-spline curve is used to fit the flight path in the enhanced safety pipeline, and the curve parameters are optimized by using the minimum cost criterion, so that the helicopter low-altitude flight path planning optimization is realized. According to the application, the state space considering the dynamic constraints and maneuvering characteristics of the helicopter is used to generate the enhanced safety pipeline in real time and to serve as the optimization space of the fitting parameters of the rear-end flight path, so that the adaptability of the planned flight path to the execution process of the helicopter is improved, and the flight safety of the helicopter under the dynamic threats at low altitude is effectively improved.

The invention discloses a two-degree-of-freedom helicopter preset performance tracking control method based on reinforcement learning. The method comprises the following steps: constructing a two-degree-of-freedom helicopter dynamic model; a preset performance function is introduced, a constrained tracking error is converted into an unconstrained form through error conversion, and therefore it is guaranteed that the system reaches a steady state within preset time; designing a preset time nonlinear disturbance observer; based on a backstepping control architecture, combining with a predefined time filter, and decomposing the system into two stages of subsystems through coordinate transformation; an optimal performance index function is constructed for each stage of subsystem, an optimal control strategy is approached online by using a reinforcement learning algorithm, and an optimal virtual controller and a self-adaptive optimal actual control law are designed. According to the method, all signals in a two-degree-of-freedom helicopter closed-loop system can be converged and bounded within predefined time, transient and steady state response indexes of the system are improved, and it is ensured that the helicopter can still rapidly and accurately track a reference trajectory under complex working conditions and quantized limited conditions.

The invention discloses a multi-platform unmanned helicopter dynamic scheduling method and system based on an improved tabu search algorithm, and relates to the field of unmanned helicopter scheduling, and the method comprises the steps: constructing a dynamic scheduling model of an unmanned helicopter; the dynamic scheduling model is used for simulating the whole process of combat-guarantee of the unmanned helicopter; constraints of the dynamic scheduling model comprise task stage logic constraints and resource constraints; solving the dynamic scheduling model based on an improved tabu search algorithm to obtain an initial scheduling scheme; carrying out local rescheduling on the initial scheduling scheme based on a multi-modal disturbance perception adaptive rescheduling strategy to obtain a rescheduling scheme; and updating the global task plan of the multi-platform unmanned helicopter based on the rescheduling scheme. According to the invention, integrated modeling of the combat mission and the guarantee operation can be realized, the dynamic environment adaptability is improved, and the accurate scheduling of the unmanned helicopter is improved.

The application discloses a kind of helicopter safety flight boundary determination method, device, equipment, medium and product, it is related to helicopter technical field, the method includes obtaining the mass center speed vector of helicopter, attitude angle vector and angular velocity vector;According to mass center speed vector, attitude angle vector and angular velocity vector utilize helicopter dynamics characteristics to construct helicopter nonlinear model and constraint range;According to the helicopter nonlinear model and the constraint range utilize alpha shape method and heuristic algorithm to determine helicopter attitude angle rate safety boundary;According to the helicopter attitude angle rate safety boundary utilizes DFoG method to determine helicopter attitude angle safety boundary;According to helicopter nonlinear model, the helicopter attitude angle rate safety boundary, the helicopter attitude angle safety boundary and the constraint range determine helicopter speed safety boundary, the application can improve the accuracy of helicopter safety flight boundary.

The application discloses a kind of based on composite cost function's helicopter dynamic route planning method and system, it is related to route planning technical field, including: obtaining the multi-source data of target area and fusion generation dynamic three-dimensional terrain model;Based on target area setting take-off point and multiple potential landing points;Based on landing point adaptability comprehensive evaluation cost function evaluation all landing points, obtain optimal landing point;Based on take-off point and optimal landing point, in combination with flight complexity cost function, obtain current optimal exploration area;Based on current optimal exploration area in combination with depth coupling cost function, screening obtains candidate flight node;Based on candidate flight node screening obtains optimal flight node of current exploration area;Based on take-off point, optimal flight node and optimal landing point obtain current optimal route;Based on current optimal route flight, and dynamically update subsequent route when abnormal. Improve the safety, efficiency and reliability of post-disaster helicopter rescue.

The application provides a kind of helicopter landing gear dynamics modeling method based on Adams, three-dimensional model of helicopter body and landing gear is respectively established, and the three-dimensional model is imported into Adams;Hydro-pneumatic buffer is equivalent to a gas spring, an oil damper and a friction damper parallel mechanism, the mathematical model of hydro-pneumatic buffer is established;Combined with Adams in Faila tire mechanics model and tire model interface, the modeling of tire vertical force, longitudinal force, lateral force and turning moment is carried out;The current time tire motion state information is obtained from the tire model interface of Adams, the tire force and torque are calculated and output, and the tire model interface is returned to Adams, the motion state of the next simulation time is calculated, and iterative analysis is carried out.The technical scheme of the application can solve the problem of long solving time and low efficiency of traditional dynamics modeling method of helicopter landing gear, realize the rapid solution of helicopter dynamics characteristics and adjustable dynamics model parameters.