CN-122020850-A - Propeller plane resistance characteristic identification method based on test data

CN122020850ACN 122020850 ACN122020850 ACN 122020850ACN-122020850-A

Abstract

The invention relates to the technical field of unmanned aerial vehicles, in particular to a method and a system for identifying resistance characteristics of a propeller aircraft based on test data, wherein the method comprises the steps of obtaining a target time point; the method comprises the steps of obtaining a correlation curve of a propeller tension coefficient and an unmanned aerial vehicle resistance coefficient at a target time point, obtaining a tension coefficient error value, and correcting the resistance coefficient to obtain a corrected resistance coefficient. The invention realizes approximate decoupling of the screw propeller tension coefficient and the aircraft resistance coefficient, breaks through the limitation of the traditional single data source or simplified model, provides high-confidence parameter reference for aerodynamic profile optimization, power system matching and flight performance evaluation of the unmanned aerial vehicle, obviously shortens the research and development period and reduces the test cost, and is particularly suitable for engineering design requirements of small and medium-sized unmanned aerial vehicles or complex configurations.

Inventors

SHEN YANHANG
CHEN YASHENG
TANG HENGXIAN
SHI ANYU
LI BOYUAN
LI DONGDONG

Assignees

西安爱生技术集团有限公司

Dates

Publication Date: 20260512
Application Date: 20260127

Claims (9)

1. A method for identifying resistance characteristics of a propeller aircraft based on test data is characterized by comprising the following steps: Acquiring two target time points when the matching weight of the unmanned aerial vehicle in a stable flight state meets the error range of the matching weight; Based on the matching weight and a mechanical balance equation, constructing a coupling relation model of the propeller tension and the unmanned aerial vehicle resistance, and acquiring a correlation curve of the propeller tension coefficient and the unmanned aerial vehicle resistance coefficient of the unmanned aerial vehicle under each target time point of stable flight state by using the coupling relation model; based on the propeller tension coefficient, acquiring the difference of the corresponding unmanned aerial vehicle resistance coefficients at two target time points according to wind tunnel test data; According to the difference of the resistance coefficients of the unmanned aerial vehicle, the correlation curves of the screw tension coefficients at two target time points and the resistance coefficients of the unmanned aerial vehicle are obtained, the actual tension coefficients in actual flight and the resistance coefficient correction values corresponding to the two target time points are obtained, and the tension coefficient error value is obtained according to the actual tension coefficients and the screw tension coefficients; When the error value of the tension coefficient is larger than a preset error threshold, the actual tension coefficient is used as the tension coefficient of the propeller, the difference of the resistance coefficient of the unmanned aerial vehicle is recalculated, and when the error value of the tension coefficient is smaller than or equal to the preset error threshold, the resistance coefficient correction deviation is obtained according to the resistance coefficient correction value corresponding to any target time point and the resistance coefficient of the unmanned aerial vehicle, and the corrected resistance coefficient is obtained by correcting the resistance coefficient based on the resistance coefficient correction deviation.
2. The method for identifying the resistance characteristics of the propeller aircraft based on the test data according to claim 1, wherein in the flight test, two approximately uniform acceleration time nodes when the unmanned aerial vehicle is in a stable horizontal flight state are selected as target time points.
3. The method for identifying the resistance characteristics of the propeller aircraft based on the test data according to claim 1, wherein the expression of the matching weight of the unmanned aerial vehicle in the stable flight state is: In the formula, The weight is matched with the unmanned aerial vehicle in a stable flight state; The lift force of the unmanned aerial vehicle is provided; is the gravity of the unmanned aerial vehicle; gravitational acceleration; Is the vacuum speed of the unmanned aerial vehicle; the rotating speed of the propeller of the unmanned aerial vehicle; is the lift coefficient; The air density at the current cruising altitude; Is the aircraft wing reference area.
4. The method for identifying the resistance characteristics of the propeller aircraft based on the test data according to claim 1, wherein the expression of the coupling relation model of the propeller tension and the unmanned aerial vehicle resistance is: In the formula, Is the pulling force of the propeller; Is aircraft resistance; The weight is matched with the unmanned aerial vehicle in a stable flight state; the rotating speed of the propeller of the unmanned aerial vehicle; Is the diameter of the propeller; is the tension coefficient of the propeller; the resistance coefficient of the unmanned aerial vehicle; The air density at the current cruising altitude; is the aircraft wing reference area; the acceleration of the unmanned plane during stable flat flight is achieved.
5. The method for identifying the resistance characteristics of the propeller aircraft based on the test data according to claim 1, wherein the difference absolute value of the corresponding unmanned aerial vehicle resistance coefficients at two target time points is used as the difference of the unmanned aerial vehicle resistance coefficients.
6. The method for identifying the resistance characteristics of the propeller aircraft based on the test data according to claim 1, wherein according to the difference of the resistance coefficients of the unmanned aerial vehicle, correlation curves of the two target time point propeller tension coefficients and the resistance coefficients of the unmanned aerial vehicle are corresponding, and an actual tension coefficient in actual flight and a resistance coefficient correction value corresponding to the two target time points are reversely solved.
7. The method according to claim 1, wherein a difference between a resistance coefficient correction value corresponding to an arbitrary target time point and a resistance coefficient of the unmanned aerial vehicle is used as a resistance coefficient correction deviation amount.
8. The method for identifying resistance characteristics of a propeller aircraft based on test data according to claim 1, wherein an absolute value of a difference between an actual tension coefficient and a propeller tension coefficient is used as the tension coefficient error value.
9. A system for identifying resistance characteristics of a propeller aircraft based on test data, comprising: the target time point selection module is used for acquiring two target time points when the matching weight of the unmanned aerial vehicle in the stable flight state meets the error range of the matching weight; the system comprises a relationship curve acquisition module, a relationship curve generation module and a control module, wherein the relationship curve acquisition module is used for constructing a coupling relationship model of propeller tension and unmanned aerial vehicle resistance based on a matching weight and a mechanical balance equation; The error acquisition module is used for acquiring the difference of the corresponding unmanned aerial vehicle resistance coefficients at two target time points based on the propeller tension coefficients and according to wind tunnel test data, acquiring the actual tension coefficients in actual flight and the resistance coefficient correction values corresponding to the two target time points according to the correlation curves of the propeller tension coefficients and the unmanned aerial vehicle resistance coefficients at the two target time points and acquiring the tension coefficient error values according to the actual tension coefficients and the propeller tension coefficients; The correction module is used for enabling the actual tension coefficient to serve as a screw tension coefficient when the tension coefficient error value is larger than a preset error threshold value, and recalculating the difference of the unmanned aerial vehicle resistance coefficient until the tension coefficient error value is smaller than or equal to the preset error threshold value, obtaining the resistance coefficient correction deviation according to the resistance coefficient correction value corresponding to any target time point and the unmanned aerial vehicle resistance coefficient, and obtaining the corrected resistance coefficient by correcting the resistance coefficient based on the resistance coefficient correction deviation.

Description

Propeller plane resistance characteristic identification method based on test data Technical Field The invention relates to the technical field of unmanned aerial vehicles, in particular to a method and a system for identifying resistance characteristics of a propeller plane based on test data. Background The aerodynamic drag characteristics of the propeller aircraft under the actual configuration and the power and tension characteristics of the propeller are difficult to accurately obtain due to the existing calculation, simulation and measurement means. At present, the method for identifying the aerodynamic parameters of the aircraft is quite various, and mainly comprises a theoretical calculation method, a method based on flight test data and a method based on wind tunnel test data. The theoretical calculation method is based on theoretical assumption and simplified model, calculates aerodynamic parameters by simulating different working conditions, and has high calculation efficiency, but has larger error and lower precision due to the limitation of model simplification and assumption, and is difficult to accurately reflect complex aerodynamic characteristics in actual flight. According to the method based on the flight test data, the flight parameters are measured by various sensors in actual flight, the aerodynamic parameters are calculated by combining with the aircraft dynamics model, and the data are closer to the real flight state. However, this method has problems in that the test conditions are difficult to control accurately, the data processing is complicated, and the cost is high. The method based on wind tunnel test data is to put the scaling model in the wind tunnel, simulate different flight conditions by adjusting wind speed, wind direction and model posture, and measure the aerodynamic force born by the model, thereby obtaining more accurate aerodynamic data rapidly. However, due to the difference between the scaling model and the full-size aircraft in terms of task load, landing gear installation and the like, the wind tunnel test result has deviation from the resistance characteristic in actual flight, and the accuracy of the wind tunnel test result in actual application is limited. The existing methods such as theoretical calculation, flight test and wind tunnel test have advantages, but are limited by model simplification errors, uncontrollable test conditions and scaling model deviation, and are difficult to realize high-precision and high-reliability pneumatic parameter identification. In particular, aiming at the flat flight working condition of the propeller aircraft, the pneumatic-propulsion coupling effect is obvious, a complex nonlinear coupling relation is formed between the tension of the propeller and the resistance of the aircraft due to the mutual interference of flow fields, and the traditional single model is limited by simplifying assumption and insufficient decoupling capability, so that the dynamic characteristics of the model are difficult to describe accurately. This limitation results in a low confidence of pneumatic parameter identification based on a single test or simulation approach, which fails to meet the engineering requirements of high-precision unmanned aerial vehicle design. Therefore, how to accurately identify the pull force of the propeller and the resistance characteristic of the airplane by combining flight test data and wind tunnel test data becomes an important technical problem in the current unmanned aerial vehicle design. The method is beneficial to improving the accuracy of unmanned aerial vehicle performance evaluation, and can provide more reliable technical support for the optimization of aircraft design, thereby promoting the further development of unmanned aerial vehicle technology. Therefore, there is a need to provide a method and a system for identifying resistance characteristics of a propeller aircraft based on test data so as to solve the above problems. Disclosure of Invention Aiming at the flat flight working condition of the propeller aircraft, the pneumatic-propulsion coupling effect is obvious, a complex nonlinear coupling relation is formed between the tension of the propeller and the resistance of the aircraft due to the mutual interference of flow fields, and the traditional single model is limited by simplifying assumption and insufficient decoupling capability, so that the dynamic characteristics of the model are difficult to describe accurately. Such limitations result in the problem that pneumatic parameter identification confidence based on a single test or simulation approach is low, and engineering requirements of high-precision unmanned aerial vehicle design cannot be met, the invention provides a method and a system for identifying resistance characteristics of a propeller aircraft based on test data, which are used for solving the existing problems. The first aspect of the invention provides a method for identifyin