CN105718727A

CN105718727A - Stratospheric airship flight performance parameter estimation method and system

Info

Publication number: CN105718727A
Application number: CN201610035229.8A
Authority: CN
Inventors: 周江华; 王帆; 苗景刚
Original assignee: Academy of Opto Electronics of CAS
Current assignee: Academy of Opto Electronics of CAS
Priority date: 2016-01-19
Filing date: 2016-01-19
Publication date: 2016-06-29
Anticipated expiration: 2036-01-19
Also published as: CN105718727B

Abstract

The invention relates to a method and system for estimating the flight performance parameters of a stratospheric airship, comprising: making the airship enter a stable hovering flight state; obtaining the ground speed, attitude information and position information of the airship; , to estimate the flight performance parameters of the airship. The method and system for estimating the flight performance parameters of a stratospheric airship provided by the present invention can calculate accurate horizontal wind speed and wind direction by using the ground speed, position, and attitude angle information given by the navigation system in the airship in a high-altitude thin atmosphere environment , airspeed, steady-state circling radius, circling period, circling angular rate, side-slip angle and angle of attack and other flight performance parameters; It can enter the circling flight state, and the circling flight keeps the airship at a fixed height, and the wind speed and wind direction are fixed, so that the airship is in a constant wind field, which reduces the error in estimating the flight performance parameters of the airship.

Description

A method and system for estimating flight performance parameters of a stratospheric airship

技术领域technical field

本发明涉及航空测控技术领域，特别涉及一种估计平流层飞艇飞行性能参数的方法和系统。The invention relates to the technical field of aviation measurement and control, in particular to a method and system for estimating flight performance parameters of a stratospheric airship.

背景技术Background technique

近年来在区域大气环境监测、防灾减灾、高分辨率实时监视、预警和导弹防御、反恐、区域通信等需求的驱动下，平流层飞艇引起了各国的普遍重视，美国、日本、俄罗斯、韩国、欧盟、中国等主要国家陆续启动了相关的研究计划，开始了较深入的研究开发工作。一些国家已经开始着手进行平流层飞艇样机的研制和飞行试验。In recent years, driven by the needs of regional atmospheric environment monitoring, disaster prevention and mitigation, high-resolution real-time monitoring, early warning and missile defense, anti-terrorism, and regional communications, stratospheric airships have attracted widespread attention from all countries. The United States, Japan, Russia, and South Korea Major countries such as China, the European Union, and China have successively launched relevant research programs and started more in-depth research and development work. Some countries have already started to develop and test the prototype of the stratospheric airship.

飞行试验是检验飞行性能指标是否满足要求、飞艇总体设计是否合理的重要依据。当前平流层飞艇尚处在探索阶段，开展一次试验飞行的周期较长，成本和代价也很大，因此往往希望能通过一次飞行试验评估出尽可能多的飞行特性参数。然而，现阶段从飞行试验中，获取平流层飞艇的飞行性能参数或飞行特性参数，存在几个根本性的困难：首先，相对风速或真风速无法测量。由于平流层环境的特殊性，目前还无法实时获取飞行时的相对风速信息(空速、攻角、侧滑角)或者真风速信息。这些信息对基础飞行特性参数的辨识至关重要，因为平流层飞艇的动力学特性与其相对于大气的移动速度相关，而非与相对地面的移动速度相关。其次，平流层飞艇处于风场环境。平流层风场并不恒定，风速/风向随高度的变化而变化，仅当高度变化很小时，才能近似看作恒定风场。由于平流层飞艇体积庞大，运动速度低，其动力学特性受风的影响很大。和低空飞艇可选择无风环境开展飞行试验不同，平流层飞艇的飞行试验无法隔离风的影响。在风速不可测的情况下，加剧了参数估计的困难。其三，平流层试验飞艇自身存在的一些不足，加剧了飞行工况保持的难度。例如，由于俯仰姿态调节困难，平流层飞艇保持定高飞行比较困难，一旦飞艇推力或空速发生变化，高度就会发生飘移，而高度飘移又往往导致艇体压力变化，产生充放气效应，使得飞艇的质量参数也发生改变。然而，保持特定的飞行工况，是通过试验方法辨识飞行特性参数的关键。The flight test is an important basis for checking whether the flight performance indicators meet the requirements and whether the overall design of the airship is reasonable. At present, the stratospheric airship is still in the exploratory stage, and the period of carrying out a test flight is long, and the cost and cost are also high. Therefore, it is often hoped that as many flight characteristic parameters as possible can be evaluated through a flight test. However, there are several fundamental difficulties in obtaining flight performance parameters or flight characteristic parameters of stratospheric airships from flight tests at this stage: First, relative wind speed or true wind speed cannot be measured. Due to the particularity of the stratospheric environment, it is currently impossible to obtain real-time relative wind speed information (airspeed, angle of attack, sideslip angle) or true wind speed information during flight. This information is crucial for the identification of basic flight characteristic parameters, since the dynamics of a stratospheric airship are related to its velocity relative to the atmosphere rather than relative to the ground. Second, the stratospheric airship is in a wind field environment. The stratospheric wind field is not constant, and the wind speed/wind direction changes with the change of height. Only when the height changes are small, it can be approximately regarded as a constant wind field. Due to the large size and low speed of the stratospheric airship, its dynamic characteristics are greatly affected by the wind. Unlike low-altitude airships, which can choose a windless environment to carry out flight tests, the flight tests of stratospheric airships cannot isolate the influence of wind. In the case of unpredictable wind speed, the difficulty of parameter estimation is exacerbated. Third, some deficiencies in the stratospheric test airship itself have exacerbated the difficulty of maintaining flight conditions. For example, due to the difficulty in adjusting the pitch attitude, it is difficult for a stratospheric airship to maintain a constant altitude flight. Once the thrust or airspeed of the airship changes, the altitude will drift, and the altitude drift will often lead to changes in the pressure of the hull, resulting in inflation and deflation effects. The quality parameters of the airship are also changed. However, maintaining specific flight conditions is the key to identifying flight characteristic parameters through experimental methods.

以风速估计为例，来说明通过试验方法评估飞行性能参数的困境。曾有人认为，可用下述方法提取风速：首先让飞艇处于无动力飘飞状态，此时导航系统，如GPS给出的地速即为风速。由于平流层风场具有较好的时间稳定性，在之后的飞行性能评估试验时，可认为风速保持不变。但实际上，平流层风场随高度分层变化，一旦动力开启，由于俯仰姿态调节的困难，几乎不可能使得飞艇保持在零攻角飞行状态，飞行高度会发生飘移，而高度变化一旦和充放气耦合，高度飘移很容易就会超过200m。此时，新高度上的风场已经不是之前飘飞时的风场。Wind speed estimation is used as an example to illustrate the dilemma of evaluating flight performance parameters by experimental methods. Someone once thought that the following method can be used to extract the wind speed: first let the airship be in a state of unpowered flight, and at this time, the ground speed given by the navigation system, such as GPS, is the wind speed. Since the stratospheric wind field has good time stability, the wind speed can be considered to remain unchanged in the subsequent flight performance evaluation tests. But in fact, the stratospheric wind field changes with the altitude layer. Once the power is turned on, it is almost impossible to keep the airship at zero angle of attack due to the difficulty of adjusting the pitch attitude, and the flight altitude will drift. With deflation coupling, the altitude drift can easily exceed 200m. At this time, the wind field at the new altitude is no longer the wind field when flying before.

数学上，平流层飞艇飞行特性参数的试验辨识问题，可归结为：在风场和空速未知的前提下，如何进行试验设计和辨识算法设计，使得仅利用相对于地面的移动轨迹、速度、姿态等其他信息，就可评估出所期望的飞行特性参数。目前在平流层及以上高度，还没有已见文献的方法能直接为平流层飞艇提供评价飞行性能所需要的实时水平风速风向、空速、稳态盘旋半径、盘旋周期、盘旋角速率、侧滑角和攻角信息。Mathematically, the experimental identification problem of the flight characteristic parameters of the stratospheric airship can be summarized as: how to design the experimental design and the identification algorithm under the premise that the wind field and airspeed are unknown, so that only the moving trajectory, speed, Attitude and other information can be used to evaluate the desired flight characteristic parameters. At present, in the stratosphere and above altitudes, there is no known method in the literature that can directly provide real-time horizontal wind speed and direction, airspeed, steady-state circling radius, circling period, circling angular rate, sideslip Angle and angle of attack information.

发明内容Contents of the invention

本发明所要解决的技术问题是如何准确估计平流层飞艇的飞行性能参数。The technical problem to be solved by the invention is how to accurately estimate the flight performance parameters of the stratospheric airship.

为此目的，本发明提出了一种估计平流层飞艇飞行性能参数的方法，包括：To this end, the present invention proposes a method for estimating the flight performance parameters of a stratospheric airship, comprising:

使所述飞艇进入稳定盘旋飞行状态；making the airship enter a stable circling flight state;

获取所述飞艇的地速、姿态信息和位置信息；Obtain the ground speed, attitude information and position information of the airship;

根据所述飞艇的地速、姿态信息和位置信息，估计所述飞艇的飞行性能参数。Estimate the flight performance parameters of the airship according to the ground speed, attitude information and position information of the airship.

优选地，所述使所述飞艇进入稳定盘旋飞行状态包括：Preferably, said making the airship enter a stable circling flight state includes:

固定所述飞艇的主桨转速和偏航控制量，使所述飞艇进入盘旋飞行状态；当所述飞艇的飞行高度的波动值小于预设值时，即认为所述飞艇进入稳定盘旋飞行状态。Fixing the speed of the main propeller and the yaw control amount of the airship, so that the airship enters a circling flight state; when the fluctuation value of the flying height of the airship is less than a preset value, it is considered that the airship enters a stable circling flight state.

优选地，所述飞艇的飞行性能参数包括风速、空速、偏航操纵性能参数和纵、横向稳定性能参数。Preferably, the flight performance parameters of the airship include wind speed, airspeed, yaw control performance parameters and longitudinal and lateral stability performance parameters.

优选地，所述风速、空速的计算过程包括：Preferably, the calculating process of described wind speed, airspeed comprises:

根据所述风速、空速和地速的关系建立第一圆方程：Establish the first circle equation according to the relationship between the wind speed, air speed and ground speed:

${(({V V}_{x x} - - {W W}_{x x}))}^{22} + + {(({V V}_{y the y} - - {W W}_{y the y}))}^{22} = = {V V}_{a a}^{22}$

其中，(V_x,V_y)为艇载导航系统测出的地速，(W_x,W_y)为待估计的风速，V_a为待估计的空速；Among them, (V _x , V _y ) is the ground speed measured by the boat navigation system, (W _x , W _y ) is the wind speed to be estimated, and Va is the air speed to be estimated _;

利用盘旋飞行时测出的多个地速(V_xi,V_yi),i＝1,2,…，通过圆拟合算法，计算待估计的风速(W_x,W_y)和待估计的空速V_a。Using multiple ground speeds (V _xi , V _yi ) measured during circling flight, i=1, 2,..., through the circle fitting algorithm, calculate the wind speed to be estimated (W _x , W _y ) and the space to be estimated Velocity V _a .

优选的，所述通过圆拟合算法，计算待估计的风速(W_x,W_y)和待估计的空速V_a的步骤包括：Preferably, the step of calculating the estimated wind speed (W _x , W _y ) and the estimated air speed V _a through the circle fitting algorithm includes:

A、通过多个地速(V_xi,V_yi),i＝1,2,…n，定义中间参数A. Define intermediate parameters through multiple ground speeds (V _xi , V _yi ), i=1, 2,...n

a＝2W_x，b＝2W_y，c＝V_a ²-(W_x ²+W_y ²)a=2W _x , b=2W _y , c=V _a ² −(W _x ² +W _y ² )

构造出最小二乘方程；Construct the least squares equation;

$[\begin{matrix} {V V}_{x x 11} & {V V}_{y the y 11} & 11 \\ {V V}_{x x 22} & {V V}_{y the y 22} & 11 \\ . . & . . & . . \\ . . & . . & . . \\ . . & . . & . . \\ {V V}_{x x n no} & {V V}_{y the y n no} & 11 \end{matrix}] [\begin{matrix} a a \\ b b \\ c c \end{matrix}] = = [\begin{matrix} {V V}_{x x 11}^{22} + + {V V}_{y the y 11}^{22} \\ {V V}_{x x 22}^{22} + + {V V}_{y the y 22}^{22} \\ . . \\ . . \\ . . \\ {V V}_{x x n no}^{22} + + {V V}_{y the y n no}^{22} \end{matrix}]$

B、求解最小二乘方程，计算出a，b，c；B. Solve the least squares equation and calculate a, b, c;

C、由a,b,c计算风速(W_x,W_y)，空速V_a。C. Calculate wind speed (W _x , W _y ) and air speed V _a from a, b, and c.

${W W}_{x x} = = \frac{a a}{22},, {W W}_{y the y} = = \frac{b b}{22},, {V V}_{a a} = = \sqrt{c c + + {W W}_{x x}^{22} + + {W W}_{y the y}^{22}}$

优选地，所述偏航操纵性能参数包括：所述飞艇的盘旋半径、盘旋周期、盘旋角速度；所述偏航操纵性能参数的计算过程包括：Preferably, the yaw maneuvering performance parameters include: the circling radius, circling period, and circling angular velocity of the airship; the calculation process of the yaw maneuvering performance parameters includes:

根据所述飞艇的盘旋轨迹，建立第二圆方程According to the circling track of the airship, establish the second circle equation

[(x-W_xt)-x₀₀]²+[(y-W_yt)-y₀₀]²＝R² [(xW _x t)-x ₀₀ ] ² +[(yW _y t)-y ₀₀ ] ² ＝R ²

其中，(W_x,W_y)为风速，(x₀₀,y₀₀)为初始时刻圆心的位置，(x,y)为艇载导航系统测出的飞艇位置，R为待估计的飞艇的盘旋半径，t为时间；Among them, (W _x , W _y ) is the wind speed, (x ₀₀ , y ₀₀ ) is the position of the center of the circle at the initial moment, (x, y) is the position of the airship measured by the on-board navigation system, and R is the circling of the airship to be estimated Radius, t is time;

从所述飞艇的盘旋轨迹上选取一系列点(x_i,y_i,t_i),i＝1,2,…，通过圆拟合算法，计算待估计的飞艇的盘旋半径R。Select a series of points (x _i , y _i , t _i ), i=1, 2, .

优选地，所述盘旋周期、盘旋角速度通过以下公式进行计算：Preferably, the spiral period and spiral angular velocity are calculated by the following formula:

$ω ω = = \frac{{V V}_{a a}}{R R}$

${T T}_{c c i i r r c c l l e e} = = \frac{22 π π}{ω ω}$

其中，ω为盘旋角速率，T_circle为盘旋周期。Among them, ω is the circle angular rate, and T _circle is the circle period.

优选地，所述纵、横向稳定性能参数包括所述飞艇的平均侧滑角、瞬时侧滑角、平均攻角和瞬时攻角；Preferably, the longitudinal and lateral stability performance parameters include the average sideslip angle, instantaneous sideslip angle, average angle of attack and instantaneous angle of attack of the airship;

所述飞艇的平均侧滑角和瞬时侧滑角通过以下公式进行计算：The average sideslip angle and instantaneous sideslip angle of the airship are calculated by the following formula:

$\overset{&OverBar; &OverBar;}{β β} = = {sin sin}^{- - 11} ((\frac{{\overset{&OverBar; &OverBar;}{V V}}_{a a,, y the y b b}}{{V V}_{a a}}))$

${β β}_{i i} = = {sin sin}^{- - 11} [[\frac{{(({V V}_{a a,, y the y b b}))}_{i i}}{{V V}_{a a}}]]$

$[\begin{matrix} {\overset{&OverBar; &OverBar;}{V V}}_{a a,, x x b b} \\ {\overset{&OverBar; &OverBar;}{V V}}_{a a,, y the y b b} \\ {\overset{&OverBar; &OverBar;}{V V}}_{a a,, z z b b} \end{matrix}] = = \frac{11}{m m} {[\begin{matrix} {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, x x b b}))}_{i i} \\ {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, y the y b b}))}_{i i} \\ {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, z z b b}))}_{i i} \end{matrix}]}_{i i}$

${[\begin{matrix} {V V}_{a a,, x x b b} \\ {V V}_{a a,, y the y b b} \\ {V V}_{a a,, z z b b} \end{matrix}]}_{i i} = = A A (({φ φ}_{i i},, {θ θ}_{i i},, {ψ ψ}_{i i})) {[\begin{matrix} {V V}_{a a,, x x} \\ {V V}_{a a,, y the y} \\ {V V}_{a a,, z z} \end{matrix}]}_{i i}$

${[\begin{matrix} {V V}_{a a,, x x} \\ {V V}_{a a,, y the y} \\ {V V}_{a a,, z z} \end{matrix}]}_{i i} = = {[\begin{matrix} {V V}_{x x} \\ {V V}_{y the y} \\ {V V}_{z z} \end{matrix}]}_{i i} - - [\begin{matrix} {W W}_{x x} \\ {W W}_{y the y} \\ 00 \end{matrix}]$

其中， ${[\begin{matrix} V_{a, x} & V_{a, x} & V_{a, z} \end{matrix}]}_{i}^{T}$ 为空速在导航坐标系下的分量； ${[\begin{matrix} V_{x} & V_{y} & V_{z} \end{matrix}]}_{i}^{T}$ 为地速在导航坐标系下的分量，[W_xW_y0]^T为风速在导航坐标系下的分量， ${[\begin{matrix} V_{a, x b} & V_{a, y b} & V_{a, z b} \end{matrix}]}_{i}^{T}$ 为空速在体轴系上的分量，A(φ_i,θ_i,ψ_i)为从导航坐标系转到体轴系的转换矩阵，m为盘旋轨迹上点的个数，i＝1,2,…,m，为平均侧滑角，β_i为t_i时刻的侧滑角， ${[\begin{matrix} {\overset{&OverBar;}{V}}_{a, x b} & {\overset{&OverBar;}{V}}_{a, y b} & {\overset{&OverBar;}{V}}_{a, z b} \end{matrix}]}^{T}$ 为空速在体轴系上的分量平均值，为空速在体轴系上的y轴方向分量平均值，(V_a,yb)_i为t_i时刻空速在体轴系上的y轴方向分量。in, ${[\begin{matrix} V_{a, x} & V_{a, x} & V_{a, z} \end{matrix}]}_{i}^{T}$ is the component of airspeed in the navigation coordinate system; ${[\begin{matrix} V_{x} & V_{the y} & V_{z} \end{matrix}]}_{i}^{T}$ is the component of the ground speed in the navigation coordinate system, [W _x W _y 0] ^T is the component of the wind speed in the navigation coordinate system, ${[\begin{matrix} V_{a, x b} & V_{a, the y b} & V_{a, z b} \end{matrix}]}_{i}^{T}$ is the component of airspeed on the body axis system, A(φ _i ,θ _i ,ψ _i ) is the transformation matrix from the navigation coordinate system to the body axis system, m is the number of points on the circle trajectory, i=1, 2,...,m, is the average sideslip angle, β _i is the sideslip angle at time t _i , ${[\begin{matrix} {\overset{&OverBar;}{V}}_{a, x b} & {\overset{&OverBar;}{V}}_{a, the y b} & {\overset{&OverBar;}{V}}_{a, z b} \end{matrix}]}^{T}$ is the average value of the airspeed components on the body axis, is the average value of the y-axis direction component of the space velocity on the body axis system, and (V _a,yb ) _i is the y-axis direction component of the space velocity on the body axis system at time t _i .

优选地，所述飞艇的平均攻角和瞬时攻角通过以下公式进行计算：Preferably, the average angle of attack and the instantaneous angle of attack of the airship are calculated by the following formula:

$\overset{&OverBar;}{α} = \tan^{- 1} (\frac{{\overset{&OverBar;}{V}}_{a, z b}}{{\overset{&OverBar;}{V}}_{a, x b}})$ 或 $\overset{&OverBar;}{α} \approx \frac{1}{m} Σ_{i = 1}^{m} θ_{i}$ $\overset{&OverBar;}{α} = {the tan}^{- 1} (\frac{{\overset{&OverBar;}{V}}_{a, z b}}{{\overset{&OverBar;}{V}}_{a, x b}})$ or $\overset{&OverBar;}{α} \approx \frac{1}{m} Σ_{i = 1}^{m} θ_{i}$

$α_{i} = \tan^{- 1} \frac{{(V_{a, b z})}_{i}}{{(V_{a, b x})}_{i}}$ 或 $α_{i} \approx θ_{i}$ $α_{i} = {the tan}^{- 1} \frac{{(V_{a, b z})}_{i}}{{(V_{a, b x})}_{i}}$ or $α_{i} \approx θ_{i}$

其中，为平均攻角，为m个俯仰角的平均值，为空速在体轴系上的z轴方向分量平均值，为空速在体轴系上的x轴方向分量平均值，α_i为t_i时刻的瞬时攻角，θ_i为t_i时刻的俯仰角，(V_a,bz)_i为t_i时刻空速在体轴系上的z轴方向分量平均值，(V_a,bx)_i为t_i时刻空速在体轴系上的x轴方向分量平均值。in, is the average angle of attack, is the average value of m pitch angles, is the average value of the z-axis direction component of airspeed on the body axis system, is the average value of airspeed components in the x-axis direction on the body axis, α _i is the instantaneous angle of attack at time t _i , θ _i is the pitch angle at time t _i , (V _a,bz ) _i is the airspeed at time t _i The average value of the z-axis direction component on the body axis system, (V _a,bx ) _i is the average value of the x-axis direction component of airspeed on the body axis system at time t _i .

另一方面，本发明还提供了一种估计平流层飞艇飞行性能参数的系统，包括：飞行单元、采集单元、估计单元；On the other hand, the present invention also provides a system for estimating flight performance parameters of a stratospheric airship, comprising: a flight unit, an acquisition unit, and an estimation unit;

所述飞行单元用于使所述飞艇进入稳定盘旋飞行状态；The flight unit is used to make the airship enter a stable circling flight state;

所述采集单元获取所述飞艇的地速、姿态信息和位置信息；The acquisition unit acquires ground speed, attitude information and position information of the airship;

所述估计单元用于根据所述飞艇的地速、姿态信息和位置信息，估计所述飞艇的飞行性能参数。The estimation unit is used for estimating the flight performance parameters of the airship according to the ground speed, attitude information and position information of the airship.

本发明提供的估计平流层飞艇飞行性能参数的方法和系统，可在高空稀薄大气环境下，利用平流层飞艇内的导航系统给出的地速、位置、姿态角信息，计算出准确的水平风速、风向、空速、偏航操纵性能(稳态盘旋半径、盘旋周期、盘旋角速率)、纵横向稳定性(侧滑角和攻角)等飞行性能参数；且本发明过程简单、易于实现，只需固定主桨转速和偏航控制量，飞艇即可进入盘旋飞行状态，盘旋飞行使飞艇处于固定高度，风速和风向固定，使飞艇处于恒定风场下，减小了估计平流层飞艇飞行性能参数的误差。The method and system for estimating the flight performance parameters of a stratospheric airship provided by the present invention can calculate the accurate horizontal wind speed by using the ground speed, position, and attitude angle information given by the navigation system in the stratospheric airship in a high-altitude thin atmosphere environment , wind direction, airspeed, yaw control performance (steady-state circling radius, circling period, circling angular rate), longitudinal and lateral stability (sideslip angle and angle of attack) and other flight performance parameters; and the process of the present invention is simple and easy to implement, Only need to fix the rotation speed of the main propeller and the yaw control amount, the airship can enter the circling flight state, the circling flight makes the airship at a fixed altitude, the wind speed and wind direction are fixed, so that the airship is under a constant wind field, which reduces the estimated flight performance of the stratospheric airship parameter error.

附图说明Description of drawings

通过参考附图会更加清楚的理解本发明的特征和优点，附图是示意性的而不应理解为对本发明进行任何限制，在附图中：The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the invention in any way. In the accompanying drawings:

图1示出了本发明一种估计平流层飞艇飞行性能参数的方法的流程示意图；Fig. 1 shows a schematic flow chart of a method for estimating the flight performance parameters of a stratospheric airship in the present invention;

图2示出了本发明一种估计平流层飞艇飞行性能参数的方法的一种实施方式的流程示意图；Fig. 2 shows a schematic flow chart of an embodiment of a method for estimating the flight performance parameters of a stratospheric airship in the present invention;

图3示出了在风场环境下地速、风速、空速矢量的关系示意图；Fig. 3 shows a schematic diagram of the relationship between ground speed, wind speed, and airspeed vectors in a wind field environment;

图4示出了风场环境下平流层飞艇的盘旋轨迹示意图；Fig. 4 shows the schematic diagram of the hovering trajectory of the stratospheric airship under the wind field environment;

图5为风场环境下盘旋轨迹摆线与圆的关系示意图；Fig. 5 is a schematic diagram of the relationship between the cycloid and the circle of the spiral trajectory in the wind field environment;

图6为侧滑角随时间的变化示意图；Figure 6 is a schematic diagram of the change of sideslip angle with time;

图7为攻角随时间的变化示意图。Figure 7 is a schematic diagram of the variation of the angle of attack with time.

具体实施方式detailed description

下面将结合附图对本发明的实施例进行详细描述。Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

如图1所示，本发明提供了一种估计平流层飞艇飞行性能参数的方法，As shown in Figure 1, the present invention provides a method for estimating the flight performance parameters of a stratospheric airship,

使飞艇进入稳定盘旋飞行状态；Make the airship enter a stable circling flight state;

获取飞艇的地速、姿态信息和位置信息；Obtain the ground speed, attitude information and position information of the airship;

根据飞艇的地速、姿态信息和位置信息，估计飞艇的飞行性能参数。According to the ground speed, attitude information and position information of the airship, the flight performance parameters of the airship are estimated.

如图2所示，其中较优的，使飞艇进入稳定盘旋飞行状态包括：固定飞艇的主桨转速和偏航控制量，使飞艇进入盘旋飞行状态；当飞艇的飞行高度的波动值小于预设值时，即认为进入稳定盘旋飞行状态。其中较优的，获取飞艇的地速、姿态信息和位置信息包括：通过飞艇的艇载导航系统获取所述飞艇的地速、姿态信息和位置信息。为了评价飞艇的飞行性能，需要获取的飞艇的飞行性能参数包括水平风速、风向、空速、偏航操纵性能参数和纵、横向稳定性能参数。其中，该方法适用于估计平流层飞艇的飞行性能参数。As shown in Figure 2, preferably, making the airship enter a stable circling flight state includes: fixing the main propeller speed and yaw control amount of the airship to make the airship enter a circling flight state; when the fluctuation value of the airship's flight altitude is less than the preset value, it is considered to enter a stable circling flight state. Preferably, acquiring the ground speed, attitude information and position information of the airship includes: acquiring the ground speed, attitude information and position information of the airship through an on-board navigation system of the airship. In order to evaluate the flight performance of the airship, the flight performance parameters of the airship that need to be obtained include horizontal wind speed, wind direction, airspeed, yaw control performance parameters and longitudinal and lateral stability performance parameters. Among others, the method is suitable for estimating flight performance parameters of stratospheric airships.

当飞艇进入稳态盘旋飞行时，空速大小保持不变，且会自动进入定高飞行状态，定高飞行时，可近似认为风场恒定，风速、风向保持不变。飞艇进入盘旋飞行后，其风速为(W_x,W_y)，地速为(V_x,V_y)，稳态盘旋飞行时可认为航速(空速)也是常数，其大小为V_a，具体的，所述风速、空速的计算过程包括：如图3所示，根据所述风速、空速和地速的关系建立第一圆方程：When the airship enters steady-state circling flight, the airspeed remains unchanged, and it will automatically enter the state of constant-altitude flight. When the airship is in constant-altitude flight, it can be approximately considered that the wind field is constant, and the wind speed and wind direction remain unchanged. After the airship enters into a circling flight, its wind speed is (W _x , W _y ), and its ground speed is (V _x , V _y ). When the airship is in a steady circling flight, it can be considered that the airspeed (airspeed) is also a constant, and its magnitude is V _a . The calculation process of described wind speed, air speed comprises: as shown in Figure 3, establishes the first circle equation according to the relation of described wind speed, air speed and ground speed:

${(({V V}_{x x} - - {W W}_{x x}))}^{22} + + {(({V V}_{y the y} - - {W W}_{y the y}))}^{22} = = {V V}_{a a}^{22} - - - - - - ((11))$

其中，圆拟合算法是通过圆上的轨迹点来估计圆心位置和半径的方法，一般圆的曲线方程为Among them, the circle fitting algorithm is a method of estimating the position and radius of the center of the circle through the trajectory points on the circle. The general curve equation of the circle is

(x-x₀)²+(y-y₀)²＝R²(2)(xx ₀ ) ² +(yy ₀ ) ² ＝R ² (2)

式中，x、y为平面上x方向和y方向的轨迹坐标，x₀、y₀为圆心的x坐标和y坐标，R为圆的半径。In the formula, x and y are the trajectory coordinates in the x and y directions on the plane, x ₀ and y ₀ are the x and y coordinates of the center of the circle, and R is the radius of the circle.

展开后为expands to

$22 {x x}_{00} x x + + 22 {y the y}_{00} y the y + + {R R}^{22} - - (({x x}_{00}^{22} + + {y the y}_{00}^{22})) = = {x x}^{22} + + {y the y}^{22} - - - - - - ((33))$

令make

$a a = = 22 {x x}_{00},, b b = = 22 {y the y}_{00},, c c = = {R R}^{22} - - (({x x}_{00}^{22} + + {y the y}_{00}^{22})) - - - - - - ((44))$

则有then there is

ax+by+c＝x²+y²(5)ax+by+c＝x ² +y ² (5)

已知轨迹点(x_i,y_i),i＝1,2,…,n，由上式可构造出最小二乘方程Given the trajectory points ( _xi ,y _i ), i=1,2,…,n, the least squares equation can be constructed from the above formula

$[\begin{matrix} {x x}_{11} & {y the y}_{11} & 11 \\ {x x}_{22} & {y the y}_{22} & 11 \\ . . & . . & . . \\ . . & . . & . . \\ . . & . . & . . \\ {x x}_{n no} & {y the y}_{n no} & 11 \end{matrix}] [\begin{matrix} a a \\ b b \\ c c \end{matrix}] = = [\begin{matrix} {x x}_{11}^{22} + + {y the y}_{11}^{22} \\ {x x}_{22}^{22} + + {y the y}_{22}^{22} \\ . . \\ . . \\ . . \\ {x x}_{n no}^{22} + + {y the y}_{n no}^{22} \end{matrix}] - - - - - - ((66))$

估计出a,b,c后，即可得到圆曲线参数(圆心位置和半径)After estimating a, b, c, you can get the parameters of the circular curve (center position and radius)

${x x}_{00} = = \frac{a a}{22},, {y the y}_{00} = = \frac{b b}{22},, R R = = \sqrt{c c + + {x x}_{00}^{22} + + {y the y}_{00}^{22}} - - - - - - ((77))$

公式(1)所述的第一圆方程与公式(2)所述的一般圆的曲线方程，参数对应关系为，地速(V_x,V_y)对应轨迹坐标x、y，待估计的风速(W_x,W_y)对应圆心坐标x₀、y₀，待估计的空速V_a对应圆半径R。则可按照上述步骤，通过地速(V_x,V_y)计算风速(W_x,W_y)和空速V_a。The first circle equation described in the formula (1) and the curve equation of the general circle described in the formula (2), the parameter correspondence relationship is that the ground speed (V _x , V _y ) corresponds to the trajectory coordinates x, y, and the wind speed to be estimated (W _x , W _y ) corresponds to the circle center coordinates x ₀ , y ₀ , and the airspeed V _a to be estimated corresponds to the circle radius R. Then the wind speed (W _x , W _y ) and the air speed V _a can be calculated from the ground speed (V _x , V _y ) according to the above steps.

所以通过圆拟合算法，计算待估计的风速(W_x,W_y)和待估计的空速V_a的步骤包括：Therefore, through the circle fitting algorithm, the steps of calculating the estimated wind speed (W _x , W _y ) and the estimated air speed V _a include:

$a a = = 22 {W W}_{x x},, b b = = 22 {W W}_{y the y},, c c = = {V V}_{a a}^{22} - - (({W W}_{x x}^{22} + + {W W}_{y the y}^{22}))$

构造出最小二乘方程；Construct the least squares equation;

因此，通过测出的多个地速(V_xi,V_yi),i＝1,2,…，以及第一圆方程可以估算出风速(W_x,W_y)和空速V_a的值。此外，风速是一个矢量，根据风速的正负也可以确定风速的方向。Therefore, through the measured multiple ground speeds (V _xi , V _yi ), i=1, 2,..., and the first circle equation The values of wind speed (W _x , W _y ) and air speed V _a can be estimated. In addition, the wind speed is a vector, and the direction of the wind speed can also be determined according to the positive or negative of the wind speed.

如图4和图5所示，在风场环境下，盘旋轨迹曲线为摆线，而非闭合圆曲线，摆线相当于轮子滚动时，轮缘所划出的轨线。若以轮心为参照，轮缘相对于轮心的轨迹仍然是个圆。其中较优的，偏航操纵性能参数包括：所述飞艇的盘旋半径、盘旋周期、盘旋角速度；所述偏航操纵性能参数的计算过程包括：As shown in Figure 4 and Figure 5, in the wind field environment, the spiral trajectory curve is a cycloid, not a closed circular curve, and the cycloid is equivalent to the trajectory drawn by the wheel rim when the wheel rolls. If the wheel center is used as a reference, the track of the rim relative to the wheel center is still a circle. Preferably, the yaw control performance parameters include: the circling radius, the circling period, and the circling angular velocity of the airship; the calculation process of the yaw control performance parameters includes:

[(x-W_xt)-x₀₀]²+[(y-W_yt)-y₀₀]²＝R²(8)[(xW _x t)-x ₀₀ ] ² +[(yW _y t)-y ₀₀ ] ² ＝R ² (8)

其中，(W_x,W_y)为风速，(x₀₀,y₀₀)为初始时刻圆心的位置，(x,y)为艇载导航系统测出的飞艇位置，R为待估计的飞艇的盘旋半径；Among them, (W _x , W _y ) is the wind speed, (x ₀₀ , y ₀₀ ) is the position of the center of the circle at the initial moment, (x, y) is the position of the airship measured by the on-board navigation system, and R is the circling of the airship to be estimated radius;

具体的，在估算出风速(W_x,W_y)后，假设初始时刻圆心的位置为(x₀₀,y₀₀)，则时刻t，圆心的位置(x₀,y₀)为Specifically, after estimating the wind speed (W _x , W _y ), assuming that the position of the center of the circle at the initial moment is (x ₀₀ , y ₀₀ ), then at time t, the position of the center of the circle (x ₀ , y ₀ ) is

$\{\begin{matrix} {x x}_{00} = = {x x}_{0000} + + {W W}_{x x} t t \\ {y the y}_{00} = = {y the y}_{0000} + + {W W}_{y the y} t t \end{matrix} - - - - - - ((99))$

飞艇相对于圆心的位置也满足一般的圆曲线方程The position of the airship relative to the center of the circle also satisfies the general circular curve equation

(x-x₀)²+(y-y₀)²＝R²(10)(xx ₀ ) ² +(yy ₀ ) ² ＝R ² (10)

将公式(9)代入上式，即可得到第二圆方程Substituting formula (9) into the above formula, we can get the second circle equation

[(x-W_xt)-x₀₀]²+[(y-W_yt)-y₀₀]²＝R²(11)[(xW _x t)-x ₀₀ ] ² +[(yW _y t)-y ₀₀ ] ² ＝R ² (11)

令make

$\{\begin{matrix} X x = = x x - - {W W}_{x x} t t \\ Y Y = = y the y - - {W W}_{y the y} t t \end{matrix} - - - - - - ((1212))$

得到如下的辨识方程get the following identification equation

[X-x₀₀]²+[Y-y₀₀]²＝R²(13)[Xx ₀₀ ] ² +[Yy ₀₀ ] ² ＝R ² (13)

取飞艇摆线轨迹上的某点为初始点，从轨迹上选取一系列点(x_i,y_i,t_i),i＝1,2,…，计算出(X_i,Y_i),i＝1,2,…，利用上述的圆拟合算法即可得到盘旋半径R的估计。Take a point on the cycloid trajectory of the airship as the initial point, select a series of points ( _xi , y _i , t _i ), i=1, 2,... from the trajectory, and calculate (X _i ,Y _i ), i = 1, 2, ..., using the above-mentioned circle fitting algorithm, the estimation of the circle radius R can be obtained.

所述盘旋周期、盘旋角速度可以通过以下公式进行计算：The circling period and circling angular velocity can be calculated by the following formula:

$ω ω = = \frac{{V V}_{a a}}{R R} - - - - - - ((1414))$

${T T}_{c c i i r r c c l l e e} = = \frac{22 π π}{ω ω} - - - - - - ((1515))$

其中较优的，所述纵、横向稳定性能参数包括所述飞艇的平均侧滑角、瞬时侧滑角、平均攻角和瞬时攻角；Preferably, the longitudinal and lateral stability performance parameters include the average sideslip angle, instantaneous sideslip angle, average angle of attack and instantaneous angle of attack of the airship;

$\overset{&OverBar; &OverBar;}{β β} = = {sin sin}^{- - 11} ((\frac{{\overset{&OverBar; &OverBar;}{V V}}_{a a,, y the y b b}}{{V V}_{a a}})) - - - - - - ((1616))$

${β β}_{i i} = = {sin sin}^{- - 11} [[\frac{{(({V V}_{a a,, y the y b b}))}_{i i}}{{V V}_{a a}}]] - - - - - - ((1717))$

$[\begin{matrix} {\overset{&OverBar; &OverBar;}{V V}}_{a a,, x x b b} \\ {\overset{&OverBar; &OverBar;}{V V}}_{a a,, y the y b b} \\ {\overset{&OverBar; &OverBar;}{V V}}_{a a,, z z b b} \end{matrix}] = = \frac{11}{m m} {[\begin{matrix} {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, x x b b}))}_{i i} \\ {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, y the y b b}))}_{i i} \\ {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, z z b b}))}_{i i} \end{matrix}]}_{i i} - - - - - - ((1818))$

${[\begin{matrix} {V V}_{a a,, x x b b} \\ {V V}_{a a,, y the y b b} \\ {V V}_{a a,, z z b b} \end{matrix}]}_{i i} = = A A (({φ φ}_{i i},, {θ θ}_{i i},, {ψ ψ}_{i i})) {[\begin{matrix} {V V}_{a a,, x x} \\ {V V}_{a a,, y the y} \\ {V V}_{a a,, z z} \end{matrix}]}_{i i} - - - - - - ((1919))$

${[\begin{matrix} {V V}_{a a,, x x} \\ {V V}_{a a,, y the y} \\ {V V}_{a a,, z z} \end{matrix}]}_{i i} = = {[\begin{matrix} {V V}_{x x} \\ {V V}_{y the y} \\ {V V}_{z z} \end{matrix}]}_{i i} - - [\begin{matrix} {W W}_{x x} \\ {W W}_{y the y} \\ 00 \end{matrix}] - - - - - - ((2020))$

其中， ${[\begin{matrix} V_{a, x} & V_{a, y} & V_{a, z} \end{matrix}]}_{i}^{T}$ 为空速在导航坐标系下的分量； ${[\begin{matrix} V_{x} & V_{y} & V_{z} \end{matrix}]}_{i}^{T}$ 为地速在导航坐标系下的分量，[W_xW_y0]^T为风速在导航坐标系下的分量， ${[\begin{matrix} V_{a, x b} & V_{a, y b} & V_{a, z b} \end{matrix}]}_{i}^{T}$ 为空速在体轴系上的分量，A(φ_i,θ_i,ψ_i)为从导航坐标系转到体轴系的转换矩阵，m为盘旋轨迹上点的个数，i＝1,2,…,m，为平均侧滑角，β_i为t_i时刻的侧滑角， ${[\begin{matrix} {\overset{&OverBar;}{V}}_{a, x b} & {\overset{&OverBar;}{V}}_{a, y b} & {\overset{&OverBar;}{V}}_{a, z b} \end{matrix}]}^{T}$ 为空速在体轴系上的分量平均值，为空速在体轴系上的y轴方向分量平均值，(V_a,yb)_i为t_i时刻空速在体轴系上的y轴方向分量。in, ${[\begin{matrix} V_{a, x} & V_{a, the y} & V_{a, z} \end{matrix}]}_{i}^{T}$ is the component of airspeed in the navigation coordinate system; ${[\begin{matrix} V_{x} & V_{the y} & V_{z} \end{matrix}]}_{i}^{T}$ is the component of the ground speed in the navigation coordinate system, [W _x W _y 0] ^T is the component of the wind speed in the navigation coordinate system, ${[\begin{matrix} V_{a, x b} & V_{a, the y b} & V_{a, z b} \end{matrix}]}_{i}^{T}$ is the component of airspeed on the body axis system, A(φ _i ,θ _i ,ψ _i ) is the transformation matrix from the navigation coordinate system to the body axis system, m is the number of points on the circle trajectory, i=1, 2,...,m, is the average sideslip angle, β _i is the sideslip angle at time t _i , ${[\begin{matrix} {\overset{&OverBar;}{V}}_{a, x b} & {\overset{&OverBar;}{V}}_{a, the y b} & {\overset{&OverBar;}{V}}_{a, z b} \end{matrix}]}^{T}$ is the average value of the airspeed components on the body axis, is the average value of the y-axis direction component of the space velocity on the body axis system, and (V _a,yb ) _i is the y-axis direction component of the space velocity on the body axis system at time t _i .

具体的，考虑到垂直方向的风速很小，所以假设为零，由地速和风速可得出空速在导航系上分量(V_a,x,V_a,y,V_a,z)Specifically, considering that the wind speed in the vertical direction is very small, it is assumed to be zero, and the airspeed component in the navigation system can be obtained from the ground speed and wind speed (V _a,x ,V _a,y ,V _a,z )

$[\begin{matrix} {V V}_{a a,, x x} \\ {V V}_{a a,, y the y} \\ {V V}_{a a,, z z} \end{matrix}] = = [\begin{matrix} {V V}_{x x} \\ {V V}_{y the y} \\ {V V}_{z z} \end{matrix}] - - [\begin{matrix} {W W}_{x x} \\ {W W}_{y the y} \\ 00 \end{matrix}] - - - - - - ((21 twenty one))$

设导航系到体轴系的姿态角为(ψ,θ,φ)，将空速由导航系变换到体轴系 $[\begin{matrix} V_{a, x b} \\ V_{a, y b} \\ V_{a, z b} \end{matrix}] = A_{n}^{b} [\begin{matrix} V_{a, x} \\ V_{a, y} \\ V_{a, z} \end{matrix}] - - - (22)$ Let the attitude angle from the navigation system to the body axis be (ψ, θ, φ), and transform the airspeed from the navigation system to the body axis $[\begin{matrix} V_{a, x b} \\ V_{a, the y b} \\ V_{a, z b} \end{matrix}] = A_{no}^{b} [\begin{matrix} V_{a, x} \\ V_{a, the y} \\ V_{a, z} \end{matrix}] - - - (twenty two)$

转换矩阵根据姿态角(ψ,θ,φ)通过下式计算得到transformation matrix According to the attitude angle (ψ, θ, φ) calculated by the following formula

对盘旋轨迹上的每一个点，按照式(21)计算出(V_a,yb)_i，i＝1,2,…,m。For each point on the spiral trajectory, (V _a,yb ) _i is calculated according to formula (21), i=1,2,...,m.

当滚动角φ较小时，(V_a,yb)_i的计算可简化为When the rolling angle φ is small, the calculation of (V _a,yb ) _i can be simplified as

(V_a,yb)_i≈[-V_xsinψ+V_ycosψ+V_asinθsinφ]_i(24)(V _a,yb ) _i ≈[-V _x sinψ+V _y cosψ+V _a sinθsinφ] _i (24)

其中，V_x,V_y分别为地速x和y方向的分量，V_a为平均空速；Among them, V _x , V _y are the components of the ground speed in the x and y directions respectively, and V _a is the average air speed;

取Pick

${\overset{&OverBar; &OverBar;}{V V}}_{a a,, y the y b b} = = \frac{11}{m m} {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, y the y b b}))}_{i i} - - - - - - ((2525))$

则有平均侧滑角为Then the average sideslip angle is

$\overset{&OverBar; &OverBar;}{β β} = = {sin sin}^{- - 11} ((\frac{{\overset{&OverBar; &OverBar;}{V V}}_{a a,, y the y b b}}{{V V}_{a a}})) - - - - - - ((2626))$

公式(26)为稳态盘旋时的平均侧滑角，相应地在每个t_i时刻，可计算出瞬时侧滑角β_i Equation (26) is the average sideslip angle in steady-state circling, correspondingly at each time t _i , the instantaneous sideslip angle β _i can be calculated

${β β}_{i i} = = {sin sin}^{- - 11} [[\frac{{(({V V}_{a a,, y the y b b}))}_{i i}}{{V V}_{a a}}]] - - - - - - ((2727))$

如图6所示，为飞艇瞬时侧滑角和平均侧滑角的曲线图，飞艇瞬时侧滑角β_i相对于平均侧滑角的波动量，反映了飞艇横向稳定性，波动量越小，飞艇横向稳定性越好。As shown in Figure 6, it is a graph of the airship's instantaneous sideslip angle and the average sideslip angle, and the airship's instantaneous sideslip angle β _i is relative to the average sideslip angle The fluctuation amount of reflects the lateral stability of the airship, the smaller the fluctuation amount, the better the lateral stability of the airship.

其中较优的，所述飞艇的平均攻角和瞬时攻角通过以下公式进行计算：Wherein preferably, the average angle of attack and the instantaneous angle of attack of the airship are calculated by the following formula:

$\overset{&OverBar;}{α} = \tan^{- 1} (\frac{{\overset{&OverBar;}{V}}_{a, z b}}{{\overset{&OverBar;}{V}}_{a, x b}})$ 或 $\overset{&OverBar;}{α} \approx \frac{1}{m} Σ_{i = 1}^{m} θ_{i} - - - (28)$ $\overset{&OverBar;}{α} = {the tan}^{- 1} (\frac{{\overset{&OverBar;}{V}}_{a, z b}}{{\overset{&OverBar;}{V}}_{a, x b}})$ or $\overset{&OverBar;}{α} \approx \frac{1}{m} Σ_{i = 1}^{m} θ_{i} - - - (28)$

$α_{i} = \tan^{- 1} \frac{{(V_{a, b z})}_{i}}{{(V_{a, b x})}_{i}}$ 或α_i≈θ_i(29) $α_{i} = {the tan}^{- 1} \frac{{(V_{a, b z})}_{i}}{{(V_{a, b x})}_{i}}$ or α _i ≈ θ _i (29)

其中为平均攻角，为m个俯仰角的平均值，为空速在体轴系上的z轴方向分量平均值，为空速在体轴系上的x轴方向分量平均值，α_i为t_i时刻的瞬时攻角，θ_i为t_i时刻的俯仰角，(V_a,bz)_i为t_i时刻空速在体轴系上的z轴方向分量平均值，(V_a,bx)_i为t_i时刻空速在体轴系上的x轴方向分量平均值。in is the average angle of attack, is the average value of m pitch angles, is the average value of the z-axis direction component of airspeed on the body axis system, is the average value of airspeed components in the x-axis direction on the body axis, α _i is the instantaneous angle of attack at time t _i , θ _i is the pitch angle at time t _i , (V _a,bz ) _i is the airspeed at time t _i The average value of the z-axis direction component on the body axis system, (V _a,bx ) _i is the average value of the x-axis direction component of airspeed on the body axis system at time t _i .

具体的，平均攻角的估计有两种方法。其一，对平飞俯仰角θ取平均，则有平均攻角为Specifically, the average angle of attack There are two methods of estimating . First, take the average of the level flight pitch angle θ, then the average attack angle is

$\overset{&OverBar; &OverBar;}{α α} \approx \approx \frac{11}{m m} {Σ Σ}_{i i = = 11}^{m m} {θ θ}_{i i} - - - - - - ((3030))$

其二，利用式(19)给出的体轴系空速分量(V_a,xb,V_a,yb,V_a,zb)_i计算Second, use the body shaft space velocity component (V _a,xb ,V _a,yb ,V _a,zb ) _i given by formula (19) to calculate

${\overset{&OverBar; &OverBar;}{V V}}_{a a,, x x b b} = = \frac{11}{m m} {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, x x b b}))}_{i i},, {\overset{&OverBar; &OverBar;}{V V}}_{a a,, z z b b} = = \frac{11}{m m} {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, z z b b}))}_{i i} - - - - - - ((3131))$

则有平均攻角为then the average angle of attack is

$\overset{&OverBar; &OverBar;}{α α} = = {tan the tan}^{- - 11} ((\frac{{\overset{&OverBar; &OverBar;}{V V}}_{a a,, z z b b}}{{\overset{&OverBar; &OverBar;}{V V}}_{a a,, x x b b}})) - - - - - - ((3232))$

相应地，在每个t_i时刻，可计算出瞬时攻角α_i Correspondingly, at each time t _i , the instantaneous angle of attack α _i can be calculated

$α_{i} = \tan^{- 1} \frac{{(V_{a, b z})}_{i}}{{(V_{a, b x})}_{i}},$ 或α_i≈θ_i(33) $α_{i} = {the tan}^{- 1} \frac{{(V_{a, b z})}_{i}}{{(V_{a, b x})}_{i}},$ or α _i ≈ θ _i (33)

如图7所示，为飞艇瞬时攻角和平均攻角的曲线图。瞬时攻角α_i相对于平均攻角的波动量，反映了飞艇纵向稳定性。波动量越小，飞艇纵向稳定性越好。As shown in Figure 7, it is a graph of the instantaneous attack angle and the average attack angle of the airship. The instantaneous angle of attack α _i relative to the mean angle of attack The amount of fluctuation reflects the longitudinal stability of the airship. The smaller the amount of fluctuation, the better the longitudinal stability of the airship.

另一方面，采用上述估计平流层飞艇飞行性能参数的方法，本发明还提供了一种估计平流层飞艇飞行性能参数的系统，包括：飞行单元、采集单元、估计单元；On the other hand, by adopting the method for estimating the flight performance parameters of a stratospheric airship, the present invention also provides a system for estimating the flight performance parameters of a stratospheric airship, comprising: a flight unit, an acquisition unit, and an estimation unit;

本发明提供的估计平流层飞艇飞行性能参数的方法和系统，可在高空稀薄大气环境下，利用飞艇内的导航系统给出的地速、位置、姿态角信息，计算出准确的水平风速、风向、空速、偏航操纵性能(稳态盘旋半径、盘旋周期、盘旋角速率)、纵横向稳定性(侧滑角和攻角)等飞行性能参数；且本发明过程简单、易于实现，只需固定主桨转速和偏航控制量，飞艇即可进入盘旋飞行状态，盘旋飞行使飞艇处于固定高度，风速和风向固定，使飞艇处于恒定风场下，减小了估计平流层飞艇飞行性能参数的误差。The method and system for estimating the flight performance parameters of a stratospheric airship provided by the present invention can calculate accurate horizontal wind speed and wind direction by using the ground speed, position, and attitude angle information given by the navigation system in the airship in a high-altitude thin atmosphere environment , airspeed, yaw control performance (steady-state circling radius, circling period, circling angular rate), longitudinal and lateral stability (sideslip angle and angle of attack) and other flight performance parameters; and the process of the present invention is simple and easy to implement, only need By fixing the speed of the main propeller and the yaw control amount, the airship can enter the state of circling flight. The circling flight keeps the airship at a fixed altitude, and the wind speed and direction are fixed, so that the airship is under a constant wind field, which reduces the time required for estimating the flight performance parameters of the stratospheric airship. error.

虽然结合附图描述了本发明的实施方式，但是本领域技术人员可以在不脱离本发明的精神和范围的情况下做出各种修改和变型，这样的修改和变型均落入由所附权利要求所限定的范围之内。Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention. within the bounds of the requirements.

Claims

1. A method for estimating the flight performance parameters of a stratospheric airship, characterized in that,

making the airship enter a stable circling flight state;

Obtain the ground speed, attitude information and position information of the airship;

Estimate the flight performance parameters of the airship according to the ground speed, attitude information and position information of the airship.

2. a kind of method for estimating the flight performance parameter of stratospheric airship according to claim 1, is characterized in that, described making described airship enter stable hover flight state comprises:

Fixing the speed of the main propeller and the yaw control amount of the airship, so that the airship enters a circling flight state; when the fluctuation value of the flying height of the airship is less than a preset value, it is considered that the airship enters a stable circling flight state.

3. according to a kind of method for estimating the flight performance parameter of stratospheric airship according to any one of claim 1-2, it is characterized in that,

The flight performance parameters of the airship include wind speed, air speed, yaw control performance parameters and longitudinal and lateral stability performance parameters.

4. a kind of method of estimating stratospheric airship flight performance parameter according to claim 3, is characterized in that, the calculation process of described wind speed, airspeed comprises:

Establish the first circle equation according to the relationship between the wind speed, air speed and ground speed:

{(({V V}_{x x} - - {W W}_{x x}))}^{22} + + {(({V V}_{y the y} - - {W W}_{y the y}))}^{22} = = {V V}_{a a}^{22}

Among them, (V _x , V _y ) is the ground speed measured by the boat navigation system, (W _x , W _y ) is the wind speed to be estimated, and Va is the air speed to be estimated _;

Using multiple ground speeds (V _xi , V _yi ) measured during circling flight, i=1, 2,…n, through the circle fitting algorithm, calculate the estimated wind speed (W _x , W _y ) and estimated Air velocity V _a .

5. a kind of method for estimating the flight performance parameter of stratospheric airship according to claim 4, is characterized in that, described by circle fitting algorithm, calculate wind speed to be estimated (W _x , W _y ) and space to be estimated The steps of speeding up V _a include:

A. Define intermediate parameters through multiple ground speeds (V _xi , V _yi ), i=1, 2,...n

a=2W _x , b=2W _y , c=V _a ² −(W _x ² +W _y ² )

Construct the least squares equation;

[\begin{matrix} {V V}_{x x 11} & {V V}_{y the y 11} & 11 \\ {V V}_{x x 22} & {V V}_{y the y 22} & 11 \\ . . & . . & . . \\ . . & . . & . . \\ . . & . . & . . \\ {V V}_{x x n no} & {V V}_{y the y n no} & 11 \end{matrix}] [\begin{matrix} a a \\ b b \\ c c \end{matrix}] = = [\begin{matrix} {V V}_{x x 11}^{22} + + {V V}_{y the y 11}^{22} \\ {V V}_{x x 22}^{22} + + {V V}_{y the y 22}^{22} \\ . . \\ . . \\ . . \\ {V V}_{x x n no}^{22} + + {V V}_{y the y n no}^{22} \end{matrix}]

B. Solve the least squares equation and calculate a, b, c;

C. Calculate wind speed (W _x , W _y ) and air speed V _a from a, b, and c.

{W W}_{x x} = = \frac{a a}{22},, {W W}_{y the y} = = \frac{b b}{22},, {V V}_{a a} = = \sqrt{c c + + {W W}_{x x}^{22} + + {W W}_{y the y}^{22}}

6. a kind of method for estimating the flight performance parameter of stratospheric airship according to claim 3, is characterized in that, described yaw maneuvering performance parameter comprises: the circling radius of described airship, circling period, circling angular velocity; The calculation process of flight control performance parameters includes:

According to the circling track of the airship, establish the second circle equation

[(xW _x t)-x ₀₀ ] ² +[(yW _y t)-y ₀₀ ] ² ＝R ²

Among them, (W _x , W _y ) is the wind speed, (x ₀₀ , y ₀₀ ) is the position of the center of the circle at the initial moment, (x, y) is the position of the airship measured by the on-board navigation system, and R is the circling of the airship to be estimated Radius, t is time;

Select a series of points (x _i , y _i , t _i ), i=1, 2, .

7. a kind of method for estimating the flight performance parameter of stratospheric airship according to claim 6, is characterized in that, described circle period, circle angular velocity are calculated by following formula:

ω ω = = \frac{{V V}_{a a}}{R R}

{T T}_{c c i i r r c c l l e e} = = \frac{22 π π}{ω ω}

Among them, ω is the circle angular rate, and T _circle is the circle period.

8. a kind of method for estimating stratospheric airship flight performance parameters according to claim 3 is characterized in that, described longitudinal and lateral stability performance parameters comprise the average sideslip angle of described airship, instantaneous sideslip angle, average attack angle and instantaneous angle of attack;

The average sideslip angle and instantaneous sideslip angle of the airship are calculated by the following formula:

\overset{&OverBar; &OverBar;}{β β} = = {sin sin}^{- - 11} ((\frac{{\overset{&OverBar; &OverBar;}{{V V}_{a a}}}_{,, y the y b b}}{{V V}_{a a}}))

{β β}_{i i} = = {sin sin}^{- - 11} [[\frac{{(({V V}_{a a,, y the y b b}))}_{i i}}{{V V}_{a a}}]]

[\begin{matrix} {\overset{&OverBar; &OverBar;}{V V}}_{a a,, x x b b} \\ {\overset{&OverBar; &OverBar;}{V V}}_{a a,, y the y b b} \\ {\overset{&OverBar; &OverBar;}{V V}}_{a a,, z z b b} \end{matrix}] = = \frac{11}{m m} {[\begin{matrix} {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, x x b b}))}_{i i} \\ {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, y the y b b}))}_{i i} \\ {Σ Σ}_{i i = = 11}^{m m} {(({V V}_{a a,, z z b b}))}_{i i} \end{matrix}]}_{i i}

{[\begin{matrix} {V V}_{a a,, x x b b} \\ {V V}_{a a,, y the y b b} \\ {V V}_{a a,, z z b b} \end{matrix}]}_{i i} = = A A (({φ φ}_{i i},, {θ θ}_{i i},, {ψ ψ}_{i i})) {[\begin{matrix} {V V}_{a a,, x x} \\ {V V}_{a a,, y the y} \\ {V V}_{a a,, z z} \end{matrix}]}_{i i}

{[\begin{matrix} {V V}_{a a,, x x} \\ {V V}_{a a,, y the y} \\ {V V}_{a a,, z z} \end{matrix}]}_{i i} = = [\begin{matrix} {V V}_{x x} \\ {V V}_{y the y} \\ {V V}_{z z} \end{matrix}] - - [\begin{matrix} {W W}_{x x} \\ {W W}_{y the y} \\ 00 \end{matrix}]

in,

{[\begin{matrix} V_{a, x} & V_{a, the y} & V_{a, z} \end{matrix}]}_{i}^{T}

is the component of airspeed in the navigation coordinate system;

{[\begin{matrix} V_{x} & V_{the y} & V_{z} \end{matrix}]}_{i}^{T}

is the component of the ground speed in the navigation coordinate system, [W _x W _y 0] ^T is the component of the wind speed in the navigation coordinate system,

{[\begin{matrix} V_{a, x b} & V_{a, the y b} & V_{a, z b} \end{matrix}]}_{i}^{T}

is the component of airspeed on the body axis system, A(φ _i ,θ _i ,ψ _i ) is the transformation matrix from the navigation coordinate system to the body axis system, m is the number of points on the circle trajectory, i=1, 2,...,m, is the average sideslip angle, β _i is the sideslip angle at time t _i ,

{[\begin{matrix} {\overset{&OverBar;}{V}}_{a, x b} & {\overset{&OverBar;}{V}}_{a, the y b} & {\overset{&OverBar;}{V}}_{a, z b} \end{matrix}]}^{T}

is the average value of the airspeed components on the body axis, is the average value of the y-axis direction component of the space velocity on the body axis system, and (V _a,yb ) _i is the y-axis direction component of the space velocity on the body axis system at time t _i .

9. a kind of method of estimating stratospheric airship flight performance parameter according to claim 8, is characterized in that, the mean angle of attack of described airship and instantaneous angle of attack are calculated by following formula:

\overset{&OverBar;}{α} = {the tan}^{- 1} (\frac{{\overset{&OverBar;}{V}}_{a, z b}}{{\overset{&OverBar;}{V}}_{a, x b}})

or

\overset{&OverBar;}{α} \approx \frac{1}{m} Σ_{i = 1}^{m} θ_{i}

α_{i} = {the tan}^{- 1} \frac{{(V_{a, b z})}_{i}}{{(V_{a, b x})}_{i}}

or α _i ≈ θ _i

in, is the average angle of attack, is the average value of m pitch angles, is the average value of the z-axis direction component of airspeed on the body axis system, is the average value of airspeed components in the x-axis direction on the body axis, α _i is the instantaneous angle of attack at time t _i , θ _i is the pitch angle at time t _i , (V _a,bz ) _i is the airspeed at time t _i The average value of the z-axis direction component on the body axis system, (V _a,bx ) _i is the average value of the x-axis direction component of airspeed on the body axis system at time t _i .

10. A system for estimating the flight performance parameters of a stratospheric airship, comprising: a flight unit, an acquisition unit, and an estimation unit;

The flight unit is used to make the airship enter a stable circling flight state;

The acquisition unit acquires ground speed, attitude information and position information of the airship;

The estimation unit is used for estimating the flight performance parameters of the airship according to the ground speed, attitude information and position information of the airship.