CN102495830A - Quaternion Hartley approximate output method based on angular velocities for aircraft during extreme flight - Google Patents

Abstract

The invention discloses a quaternion Hartley approximate output method based on angular velocities for an aircraft during extreme flight, which is used for solving the technical problem of poor precision of quaternion outputted by existing inertial equipment when an aircraft is in extreme flight. The technical scheme includes that approximate description for a rolling angular velocity p, a pitching angular velocity q and a yawing angular velocity r is realized by the aid of a Hartley polynomial, a quaternion state transition matrix second-order approximant is directly obtained, a quaternion state transition matrix is also directly obtained, iterative computation precision of specified quaternion is guaranteed, and accordingly output precision of inertial equipment is improved when the aircraft is in extreme flight.

Description

The approximate output intent of hypercomplex number Hartley during based on the aircraft extreme flight of angular velocity

Technical field

The present invention relates to a kind of attitude output intent of air craft carried inertial equipment, the approximate output intent of hypercomplex number Hartley when particularly relating to a kind of aircraft extreme flight based on angular velocity.

Background technology

Usually, the acceleration of rigid motion, angular velocity and attitude etc. all depend on inertial equipment output, and the output accuracy that therefore improves inertial equipment has clear and definite practical significance.The rigid motion differential equation is in most of the cases all adopted in spatial movements such as aircraft, torpedo, spacecraft; And the differential equation of portrayal rigid body attitude is a core wherein, is that pitching, lift-over and crab angle are described with three Eulerian angle usually, all resolves back output by pitching in the airborne inertial equipment, lift-over and yaw rate usually.When rigid body when the angle of pitch is ± 90 °, roll angle and crab angle can't definite values, it is excessive that error is found the solution in the zone of closing on this singular point simultaneously, causes intolerable error on the engineering and can not use; For fear of this problem, people adopt the method for restriction angle of pitch span, and this makes equation degenerate, attitude work entirely, thereby be difficult to be widely used in engineering practice.For this reason, people are based on the direct measured value of the pitching in the airborne inertial equipment, lift-over and yaw rate, and have adopted output flight attitudes such as direction cosine method, equivalent gyration vector method, hypercomplex number method.

Direction cosine method has been avoided Euler method " unusual " phenomenon, and calculating attitude matrix with direction cosine method does not have the equation degenerate problem, attitude work entirely; But need find the solution nine differential equations; Calculated amount is bigger, and real-time is relatively poor, can't satisfy the engineering practice requirement.Equivalence gyration vector method such as list appearance recursion, Shuangzi appearance gyration vector, three increment gyration vectors and four increment rotating vector methods and various correction algorithms on this basis and recursive algorithm etc.When studying rotating vector in the document, all be based on the algorithm that rate gyro is output as angle increment.Yet in actual engineering, the output of some gyros is angle rate signals, like optical fibre gyro, dynamic tuned gyroscope etc.When rate gyro was output as angle rate signal, the Algorithm Error of rotating vector method obviously increased.The hypercomplex number method is the most widely used method; This method is that the function of four Eulerian angle of definition calculates the boat appearance; Can effectively remedy the singularity of Euler method; As long as separate four differential equation of first order formula groups, analogy has tangible minimizing to cosine attitude matrix differential equation calculated amount, can satisfy in the engineering practice requirement to real-time.Its The common calculation methods has (Paul G.Savage.A Unified Mathematical Framework for Strapdown Algorithm Design [J] .Journal of guidance such as the card of finishing approximatioss, second order, fourth-order Runge-Kutta method and three rank Taylor expansion methods; Control; And dynamics; 2006,29 (2): 237-248).Finishing card approximatioss essence is list appearance algorithm, can not compensate by exchange error what limited rotation caused, and the algorithm drift under high current intelligence in the attitude algorithm can be very serious.When adopting fourth-order Runge-Kutta method to find the solution the hypercomplex number differential equation,, the trigonometric function value can occur to exceed ± 1 phenomenon, disperse thereby cause calculating along with the continuous accumulation of integral error.The Taylor expansion method also is restricted because of the deficiency of computational accuracy; Particularly for the aircraft maneuvering flight; The attitude orientation angular speed is all bigger usually; And the estimated accuracy of attitude proposed requirements at the higher level, and parameters such as hypercomplex number confirm that the error of bringing makes said method in most cases can not satisfy engineering precision.

Summary of the invention

The problem of inertial equipment output hypercomplex number low precision when overcoming existing aircraft extreme flight, the approximate output intent of hypercomplex number Hartley when the present invention provides a kind of aircraft extreme flight based on angular velocity.This method adopts the Hartley polynomial expression to lift-over, pitching, yaw rate p; Q, r carry out close approximation to be described, and directly obtains the hypercomplex number state-transition matrix; Can guarantee to confirm the iterative computation precision of hypercomplex number, thus inertial equipment output hypercomplex number precision when improving the aircraft extreme flight;

The technical solution adopted for the present invention to solve the technical problems is: the approximate output intent of hypercomplex number Hartley during a kind of aircraft extreme flight based on angular velocity is characterized in may further comprise the steps:

According to hypercomplex number continuous state equation

$\stackrel{\·}{e}=A_{e}e$

And discrete state equations

e(k+1)＝Φ _e[(k+1)T，kT]e(k)

E=[e wherein ₁, e ₂, e ₃, e ₄] ^T $A_e=\frac{1}{2}\left[\begin{array}{cccc}0& -p& -q& -r\\ p& 0& r& -q\\ q& -r& 0& p\\ r& q& -p& 0\end{array}\right]$

Ф _e[(k+1) T, kT] is A _eState-transition matrix, T is the sampling period, in full symbol definition is identical;

P, q, r are respectively lift-over, pitching, the yaw rate that inertial equipment is directly measured; Eulerian angle

θ, ψ refers to lift-over, pitching, crab angle respectively;

State-transition matrix is according to approximant

${\mathrm{\Φ}}_e[(k+1)T,\mathrm{kT}]\≈I+\mathrm{\ΠH\ξ}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}+\mathrm{\Π\Ω}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}{H}^T{\mathrm{\Π}}_1-\mathrm{\ΠH\ξ}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}\mathrm{\ΠH\ξ}\left(\mathrm{kT}\right)$

And e (k+1)=Φ _e[(k+1) T, kT] e (k) obtains the time updating value of hypercomplex number;

Wherein $I=\left[\begin{array}{cccc}1& 0& 0& 0\\ 0& 1& 0& 0\\ 0& 0& 1& 0\\ 0& 0& 0& 1\end{array}\right]$

$\mathrm{\ξ}\left(t\right)={\left[\begin{array}{ccccccc}{\mathrm{\ξ}}_{-n}\left(t\right)& ...& {\mathrm{\ξ}}_{-1}\left(t\right)& {\mathrm{\ξ}}_0\left(t\right)& {\mathrm{\ξ}}_1\left(t\right)& ...& {\mathrm{\ξ}}_n\left(t\right)\end{array}\right]}_{(2n+1)\×1}^T$

ξ _i(t)＝cas(iωt)＝cos(iωt)+sin(iωt)，(i＝-n，-n+1，…，-1，0，1，2，…，n)

ω is an angular frequency; Lift-over, pitching, yaw rate p, q, the Hartley expansion of r is respectively

p(t)＝[p _-n…p _-1?p ₀?p ₁…p _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

q(t)＝[q _-n…q _-1?q ₀?q ₁…q _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

r(t)＝[r _-n…r _-1?r ₀?r ₁…r _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

$\mathrm{\Π}=\frac{1}{2}\{\left[\begin{array}{cccc}0& -1& 0& 0\\ 1& 0& 0& 0\\ 0& 0& 0& 1\\ 0& 0& -1& 0\end{array}\right]\left[\begin{array}{ccccccc}{p}_{-n}& ...& p_{-1}& p_0& p_1& ...& p_n\end{array}\right]$

$+\left[\begin{array}{cccc}0& 0& -1& 0\\ 0& 0& 0& -1\\ 1& 0& 0& 0\\ 0& 1& 0& 0\end{array}\right]\left[\begin{array}{ccccccc}{q}_{-n}& ...& q_{-1}& q_0& q_1& ...& q_n\end{array}\right]+\left[\begin{array}{cccc}0& 0& 0& -1\\ 0& 0& 1& 0\\ 0& -1& 0& 0\\ 1& 0& 0& 0\end{array}\right]\left[\begin{array}{ccccccc}{r}_{-n}& ...& r_{-1}& r_0& r_1& ...& r_n\end{array}\right]\}$

${\mathrm{\Π}}_1=\frac{1}{2}\{{\left[\begin{array}{ccccccc}{p}_{-n}& ...& p_{-1}& p_0& p_1& ...& p_n\end{array}\right]}^T\left[\begin{array}{cccc}0& -1& 0& 0\\ 1& 0& 0& 0\\ 0& 0& 0& 1\\ 0& 0& -1& 0\end{array}\right]$

$+{\left[\begin{array}{ccccccc}{q}_{-n}& ...& q_{-1}& q_0& q_1& ...& q_n\end{array}\right]}^T\left[\begin{array}{cccc}0& 0& -1& 0\\ 0& 0& 0& -1\\ 1& 0& 0& 0\\ 0& 1& 0& 0\end{array}\right]+{\left[\begin{array}{ccccccc}{r}_{-n}& ...& r_{-1}& r_0& r_1& ...& r_n\end{array}\right]}^T\left[\begin{array}{cccc}0& 0& 0& -1\\ 0& 0& 1& 0\\ 0& -1& 0& 0\\ 1& 0& 0& 0\end{array}\right]\}$

${\∫}_0^t{\mathrm{\ξ}}_0\left(t\right)\mathrm{dt}=t=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}\frac{1}{n}& ...& \frac{1}{2}& 1& \mathrm{\π}& -1& \frac{1}{2}& ...& \frac{1}{n}\end{array}\right]$

${\∫}_0^t{\mathrm{\ξ}}_{-n}\left(t\right)\mathrm{dt}=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}0& ...& 0& 0& -\frac{1}{n}& 0& 0& ...& \frac{1}{n}\end{array}\right]$

${\∫}_0^t{\mathrm{\ξ}}_{-n}\left(t\right)\mathrm{dt}=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}-\frac{1}{n}& 0& ...& 0& \frac{1}{n}& 0& ...\∈& 0& 0\end{array}\right]$

The invention has the beneficial effects as follows: because the lift-over, pitching, the yaw rate p that adopt the Hartley polynomial expression that inertial equipment is directly exported; Q; R carries out close approximation to be described; It is approximant directly to have obtained hypercomplex number state-transition matrix second order, has guaranteed the iterative computation precision of definite hypercomplex number, thus inertial equipment output accuracy when having improved the aircraft extreme flight.

Below in conjunction with embodiment the present invention is elaborated.

Embodiment

According to hypercomplex number continuous state equation

$\stackrel{\·}{e}=A_{e}e$

And discrete state equations

e(k+1)＝Φ _e[(k+1)T，kT]e(k)

In the formula, e=[e ₁, e ₂, e ₃, e ₄] ^T $A_e=\frac{1}{2}\left[\begin{array}{cccc}0& -p& -q& -r\\ p& 0& r& -q\\ q& -r& 0& p\\ r& q& -p& 0\end{array}\right]$

Ф _e[(k+1) T, kT] is A _eState-transition matrix, T is the sampling period,

P, q, r are respectively lift-over, pitching, yaw rate; Eulerian angle

θ, ψ refers to lift-over, pitching, crab angle respectively;

State-transition matrix is according to approximant

${\mathrm{\Φ}}_e[(k+1)T,\mathrm{kT}]\≈I+\mathrm{\ΠH\ξ}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}+\mathrm{\Π\Ω}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}{H}^T{\mathrm{\Π}}_1-\mathrm{\ΠH\ξ}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}\mathrm{\ΠH\ξ}\left(\mathrm{kT}\right)$

And e (k+1)=Φ _e[(k+1) T, kT] e (k) obtains the time updating value of hypercomplex number;

Wherein $I=\left[\begin{array}{cccc}1& 0& 0& 0\\ 0& 1& 0& 0\\ 0& 0& 1& 0\\ 0& 0& 0& 1\end{array}\right]$

$\mathrm{\ξ}\left(t\right)={\left[\begin{array}{ccccccc}{\mathrm{\ξ}}_{-n}\left(t\right)& ...& {\mathrm{\ξ}}_{-1}\left(t\right)& {\mathrm{\ξ}}_0\left(t\right)& {\mathrm{\ξ}}_1\left(t\right)& ...& {\mathrm{\ξ}}_n\left(t\right)\end{array}\right]}_{(2n+1)\×1}^T$

ξ _i(t)＝cas(iωt)＝cos(iωt)+sin(iωt)，(i＝-n，-n+1，…，-1，0，1，2，…，n)

Lift-over, pitching, yaw rate p, q, the Hartley expansion of r is respectively

p(t)＝[p _-n…p _-1?p ₀?p ₁…p _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

q(t)＝[q _-n…q _-1?q ₀?q ₁…q _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

r(t)＝[r _-n…r _-1?r ₀?r ₁…r _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

$\mathrm{\Π}=\frac{1}{2}\{\left[\begin{array}{cccc}0& -1& 0& 0\\ 1& 0& 0& 0\\ 0& 0& 0& 1\\ 0& 0& -1& 0\end{array}\right]\left[\begin{array}{ccccccc}{p}_{-n}& ...& p_{-1}& p_0& p_1& ...& p_n\end{array}\right]$

$+\left[\begin{array}{cccc}0& 0& -1& 0\\ 0& 0& 0& -1\\ 1& 0& 0& 0\\ 0& 1& 0& 0\end{array}\right]\left[\begin{array}{ccccccc}{q}_{-n}& ...& q_{-1}& q_0& q_1& ...& q_n\end{array}\right]+\left[\begin{array}{cccc}0& 0& 0& -1\\ 0& 0& 1& 0\\ 0& -1& 0& 0\\ 1& 0& 0& 0\end{array}\right]\left[\begin{array}{ccccccc}{r}_{-n}& ...& r_{-1}& r_0& r_1& ...& r_n\end{array}\right]\}$

${\mathrm{\Π}}_1=\frac{1}{2}\{{\left[\begin{array}{ccccccc}{p}_{-n}& ...& p_{-1}& p_0& p_1& ...& p_n\end{array}\right]}^T\left[\begin{array}{cccc}0& -1& 0& 0\\ 1& 0& 0& 0\\ 0& 0& 0& 1\\ 0& 0& -1& 0\end{array}\right]$

$+{\left[\begin{array}{ccccccc}{q}_{-n}& ...& q_{-1}& q_0& q_1& ...& q_n\end{array}\right]}^T\left[\begin{array}{cccc}0& 0& -1& 0\\ 0& 0& 0& -1\\ 1& 0& 0& 0\\ 0& 1& 0& 0\end{array}\right]+{\left[\begin{array}{ccccccc}{r}_{-n}& ...& r_{-1}& r_0& r_1& ...& r_n\end{array}\right]}^T\left[\begin{array}{cccc}0& 0& 0& -1\\ 0& 0& 1& 0\\ 0& -1& 0& 0\\ 1& 0& 0& 0\end{array}\right]\}$

${\∫}_0^t{\mathrm{\ξ}}_0\left(t\right)\mathrm{dt}=t=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}\frac{1}{n}& ...& \frac{1}{2}& 1& \mathrm{\π}& -1& \frac{1}{2}& ...& \frac{1}{n}\end{array}\right]$

${\∫}_0^t{\mathrm{\ξ}}_{-n}\left(t\right)\mathrm{dt}=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}0& ...& 0& 0& -\frac{1}{n}& 0& 0& ...& \frac{1}{n}\end{array}\right]$

${\∫}_0^t{\mathrm{\ξ}}_{-n}\left(t\right)\mathrm{dt}=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}-\frac{1}{n}& 0& ...& 0& \frac{1}{n}& 0& ...\∈& 0& 0\end{array}\right]$

When inertial equipment is directly exported lift-over, pitching, yaw rate p, q, r adopt three rank to approach when describing, and the gained result is also near O (T ³), compare the O (T that finishes methods such as card approaches ²) precision will height.

Claims (1)

1. the approximate output intent of hypercomplex number Hartley during an aircraft extreme flight based on angular velocity is characterized in that may further comprise the steps:

According to hypercomplex number continuous state equation

$\stackrel{\·}{e}=A_{e}e$

And discrete state equations

e(k+1)＝Φ _e[(k+1)T，kT]e(k)

E=[e wherein ₁, e ₂, e ₃, e ₄] ^T $A_e=\frac{1}{2}\left[\begin{array}{cccc}0& -p& -q& -r\\ p& 0& r& -q\\ q& -r& 0& p\\ r& q& -p& 0\end{array}\right]$

Ф _e[(k+1) T, kT] is A _eState-transition matrix, T is the sampling period, in full symbol definition is identical;

P, q, r are respectively lift-over, pitching, the yaw rate that inertial equipment is directly measured; Eulerian angle θ, ψ refers to lift-over, pitching, crab angle respectively;

State-transition matrix is according to approximant

${\mathrm{\Φ}}_e[(k+1)T,\mathrm{kT}]\≈I+\mathrm{\ΠH\ξ}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}+\mathrm{\Π\Ω}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}{H}^T{\mathrm{\Π}}_1-\mathrm{\ΠH\ξ}\left(t\right){|}_{\mathrm{kT}}^{(k+1)T}\mathrm{\ΠH\ξ}\left(\mathrm{kT}\right)$

And e (k+1)=Φ _e[(k+1) T, kT] e (k) obtains the time updating value of hypercomplex number;

Wherein $I=\left[\begin{array}{cccc}1& 0& 0& 0\\ 0& 1& 0& 0\\ 0& 0& 1& 0\\ 0& 0& 0& 1\end{array}\right]$

$\mathrm{\ξ}\left(t\right)={\left[\begin{array}{ccccccc}{\mathrm{\ξ}}_{-n}\left(t\right)& ...& {\mathrm{\ξ}}_{-1}\left(t\right)& {\mathrm{\ξ}}_0\left(t\right)& {\mathrm{\ξ}}_1\left(t\right)& ...& {\mathrm{\ξ}}_n\left(t\right)\end{array}\right]}_{(2n+1)\×1}^T$

ξ _i(t)=cas (i ω t)=cos (i ω t)+sin (i ω t), (i=-n ,-n+1 ... ,-1,0,1,2 ..., n) ω is an angular frequency; Lift-over, pitching, yaw rate p, q, the Hartley expansion of r is respectively

p(t)＝[p _-n…p _-1?p ₀?p ₁…p _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

q(t)＝[q _-n…q _-1?q ₀?q ₁…q _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

r(t)＝[r _-n…r _-1?r ₀?r ₁…r _n][ξ _-n(t)…ξ _-1(t)ξ ₀(t)ξ ₁(t)…ξ _n(t)] ^T

$\mathrm{\Π}=\frac{1}{2}\{\left[\begin{array}{cccc}0& -1& 0& 0\\ 1& 0& 0& 0\\ 0& 0& 0& 1\\ 0& 0& -1& 0\end{array}\right]\left[\begin{array}{ccccccc}{p}_{-n}& ...& p_{-1}& p_0& p_1& ...& p_n\end{array}\right]$

$+\left[\begin{array}{cccc}0& 0& -1& 0\\ 0& 0& 0& -1\\ 1& 0& 0& 0\\ 0& 1& 0& 0\end{array}\right]\left[\begin{array}{ccccccc}{q}_{-n}& ...& q_{-1}& q_0& q_1& ...& q_n\end{array}\right]+\left[\begin{array}{cccc}0& 0& 0& -1\\ 0& 0& 1& 0\\ 0& -1& 0& 0\\ 1& 0& 0& 0\end{array}\right]\left[\begin{array}{ccccccc}{r}_{-n}& ...& r_{-1}& r_0& r_1& ...& r_n\end{array}\right]\}$

${\mathrm{\Π}}_1=\frac{1}{2}\{{\left[\begin{array}{ccccccc}{p}_{-n}& ...& p_{-1}& p_0& p_1& ...& p_n\end{array}\right]}^T\left[\begin{array}{cccc}0& -1& 0& 0\\ 1& 0& 0& 0\\ 0& 0& 0& 1\\ 0& 0& -1& 0\end{array}\right]$

$+{\left[\begin{array}{ccccccc}{q}_{-n}& ...& q_{-1}& q_0& q_1& ...& q_n\end{array}\right]}^T\left[\begin{array}{cccc}0& 0& -1& 0\\ 0& 0& 0& -1\\ 1& 0& 0& 0\\ 0& 1& 0& 0\end{array}\right]+{\left[\begin{array}{ccccccc}{r}_{-n}& ...& r_{-1}& r_0& r_1& ...& r_n\end{array}\right]}^T\left[\begin{array}{cccc}0& 0& 0& -1\\ 0& 0& 1& 0\\ 0& -1& 0& 0\\ 1& 0& 0& 0\end{array}\right]\}$

${\∫}_0^t{\mathrm{\ξ}}_0\left(t\right)\mathrm{dt}=t=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}\frac{1}{n}& ...& \frac{1}{2}& 1& \mathrm{\π}& -1& \frac{1}{2}& ...& \frac{1}{n}\end{array}\right]$

${\∫}_0^t{\mathrm{\ξ}}_{-n}\left(t\right)\mathrm{dt}=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}0& ...& 0& 0& -\frac{1}{n}& 0& 0& ...& \frac{1}{n}\end{array}\right]$

${\∫}_0^t{\mathrm{\ξ}}_{-n}\left(t\right)\mathrm{dt}=\frac{\mathrm{\ξ}\left(t\right)}{2\mathrm{\π}}\left[\begin{array}{ccccccccc}-\frac{1}{n}& 0& ...& 0& \frac{1}{n}& 0& ...\∈& 0& 0\end{array}\right]$