Embodiment
For example the present invention is further described below:
In the step 1 according to given desired track point calculate planning rectilinear path parameter x '
d, y '
dAnd z '
dDetailed process do
According to the adjacent expected path point WP that sets
i=(x
i, y
i, z
i) and WP
I+1=(x
I+1, y
I+1, z
I+1) coordinate information calculate the parameter x of this section expectation rectilinear path '
d, '
dAnd z '
dConcrete form
Therefore by a WP
i=(x
i, y
i, z
i) and WP
I+1=(x
I+1, y
I+1, z
I+1) the line parametrization equation that constitutes the path of 3 d-line can be expressed as
x
d(s)=x′
ds+x
i
y
d(s)=y′
ds+y
i (2)
z
d(s)=z′
ds+z
i
S is a path parameter, the speed u of defining virtual guide point P
pDirection is the angle ψ along the tangential direction of straight line path and fixed coordinate system transverse axis
FFor
ψ
F=arctan(y′
d/x′
d) (3)
Velocity vector u
pAngle theta with the fixed coordinate system Z-axis
FBe defined as
Where
for the three-dimensional linear track in terms of the presence
{ initial position under the I} is η to given then AUV at fixed coordinate system
n=[x, y, z]
T, the initial bow of AUV is respectively ψ and θ to angle and trim angle, AUV longitudinal velocity u, transverse velocity v and vertical velocity w, yaw angle speed r and pitch velocity q.
So far accomplished the initialization setting in the step 1.
Calculate the three-dimensional Track In Track error of AUV x in the step 2
e, y
eAnd z
eDetailed process following:
Definition desired track l
k{ position vector under the I} does at fixed coordinate system to go up virtual guide P
{ position vector under the I} is η to AUV current point Q at fixed coordinate system
n=[x, y, z]
T, ε=[x
e, y
e, z
e]
TFor { tracking error under the F} coordinate system is so tracking error ε can be expressed as
Wherein
is that { I} is to the coordinate system { rotation matrix of F} for fixed coordinate system; To formula (5) differentiate, get the Track In Track error equation
For rectilinear path, there be
and
to set up, formula (7) substitution formula (6) is put in order
Wherein
v
b=[v
t, 0,0]
TFor AUV resultant velocity vector, satisfy
{ B} is to the fixed coordinate system { rotation matrix of I} for the satellite coordinate system;
The relation that can be known desired track scalar parameter and " virtual guide " translational speed by differential geometric theory does
v
F=[u
p, 0,0]
TFor the velocity vector of virtual guide under the F} coordinate system, substitution formula (8)
(9)
Wherein
Put in order to such an extent that AUV pursuit movement error model does
Here
ψ wherein
e=ψ-ψ
F, θ
e=θ-θ
F
Calculate translational speed, AUV trim angle tracing deviation and the bow of " virtual guide " virtual controlling amount respectively by following formula in the step 3 to the angle tracking deviation:
(1) design " virtual guide " translational speed
u
p=v
t?cosψ
e?cosθ
e+k
1x
e (12)
K wherein
1>0 is the design of Controller parameter.
(2) AUV trim angle tracing deviation virtual controlling amount of equal value
α
θ=c
2z
e (13)
C wherein
2>0 is the design of Controller parameter.
(3) AUV yaw angle tracing deviation virtual controlling amount of equal value
α
ψ=-c
1y
e (14)
C wherein
1>0 is the design of Controller parameter.
Design virtual controlling amount u based on feedback gain contragradience method in the step 3
p, α
θAnd α
ψConcrete steps for choosing the Lyapunov energy function do
Wherein
formula (14) both sides differentiate is got by formula
(16)
The translational speed of design " virtual guide " point does
u
p=k
1x
e+v
t?cos
e?cosθ
e,k
1>0 (17)
Formula (16) becomes
Formula (18) is rewritten as following form
(19)
Designing the virtual controlling amount respectively does
α
ψ=-c
1y
e,c
1>0 (20)
α
θ=c
2z
e,c
2>0 (21)
Formula (20) and (21) substitution formula (19) are got
(22)
Z wherein
1=ψ
e-α
ψ, z
2=θ
e-α
θBecause
The limit exists, and for
Condition is set up, so satisfy
Condition is set up; Because
The limit exists, simultaneously
And
So satisfy
Condition is set up.
Calculate AUV pitch velocity and yaw angle speed virtual controlling amount respectively according to following formula in the step 4:
(1) AUV yaw angle speed virtual controlling amount
α
r=-c
3z
1 (23)
C wherein
3>0 is design of Controller parameter z
1=ψ
e-α
ψ
(2) AUV pitch velocity virtual controlling amount
α
q=-c
4z
2 (24)
C wherein
4>0 is the design of Controller parameter, z
2=θ
e-α
θ
Design AUV pitch velocity and yaw angle speed virtual controlling amount α in the step 4
qAnd α
rThe following convolution of step (15) structure Lyapunov function do
P wherein
1And p
2For the design of Controller parameter, satisfy p
1>0, p
2>0; To formula (25) both sides differentiate, formula (22) substitution arrangement is obtained
Defining variable wherein
Satisfy k
2>0, k
3>0 condition is set up.
Formula (26) is put in order
Wherein
Obtained by formula (10)~(11) and (28)~(29), formula (27) becomes
Following formula is rewritten as
Owing in step 2, designed virtual controlling amount α
ψAnd α
θSuc as formula (20) and (21), so formula (30) can be changed into
Design controller parameters
and
eliminate the nonlinear coupling term to get
(33)
Here design virtual controlling amount α
qAnd α
rBe respectively:
α
r=-c
3z
1 (34)
α
q=-c
4z
2 (35)
C wherein
3And c
4Be the design of Controller parameter
Then formula (33) becomes
(36)
Z wherein
3=r/cos θ-α
r, z
4=q-α
q, choose parameter c
3Satisfy c
3>c
1v
tCondition is set up; Choose parameter c
4Satisfy c
4>c
2v
tCondition is set up.
In the step 5, it is following to resolve AUV actuating mechanism controls command signal form:
(1) AUV propeller thrust control input signals
(2) AUV Trimming Moment control input signals
τ
q=γ
1z
e-γ
2θ
e-γ
3q-c
2c
4v
t?sinθ
e-f
q?(38)
(3) AUV changes bow Torque Control input signal
τ
r=-λ
1y
e-λ
2ψ
e-λ
3r-m
5(c
1c
3v
t?cosθ?sinψ
e?cosθ
e+qr?tanθ)-f
r (40)
Wherein
The concrete steps that obtain AUV three-dimensional path tracking control unit in the step 5 do
According to AUV actual measurement hydrodynamic force coefficient, ignore the influence of rolling motion to model, it is following to obtain AUV five degree of freedom mathematical model
Wherein
g
1=(W-B)cosθ,g
2=(z
gW-z
bB)sinθ
d
1=X
u+X
u|u||u|,d
2=Y
v+Y
v|v||v|(44)
d
3=Z
w+Z
w|w||w|,d
4=M
q+M
q|q||q|
d
5=N
r+N
r|r||r|
Wherein, state variable u, v, w, q and r represent carrier coordinate system { longitudinal velocity of AUV, transverse velocity, vertical velocity, pitch velocity and yaw angle speed under the B} respectively; M and m () represent AUV quality and the additional mass that is produced by the fluid effect, I respectively
yBe the moment of inertia of AUV around the y axle, I
zBe the moment of inertia of AUV around the z axle, X
(), Y
(), Z
(), M
()And N
()Be the viscous fluid hydrodynamic force coefficient; z
gAnd z
bBe respectively under the carrier coordinate coordinate position of center of gravity and centre of buoyancy on the Z-axis, W and B represent gravity and the buoyancy that AUV receives, d respectively
()Be nonlinear damping hydrodynamic force item, control input F
u, τ
qAnd τ
rRepresent AUV propeller thrust, trim control moment respectively and change the bow control moment.
Convolution (25) structure Lyapunov function does
To the differentiate of following formula both sides, formula (36) substitution put in order
Variable k wherein
4And k
5Be defined as
And it is full
Foot k
4>0 and k
5>0 condition is set up.
Wherein
Got by formula (47) and (48), formula (46) becomes
(49)
Here convolution (44) design AUV three-dimensional path is followed the tracks of Dynamics Controller and is done
Formula (50) substitution formula (49) can be got
(51)
To sum up can work as the design of Controller parameter and satisfy c
1>0, c
2>c
1v
t, c
3>0, c
4>c
3v
t,
p
3>0, p
4>0, c
5>0, c
6Under>0 prerequisite, and if only if (u
e, x
e, y
e, z
e, z
1, z
2, z
3, z
4)=0 o'clock,
Can be got by the LaSalle invariance principle, closed loop tracking error system is asymptotic stable.
Emulation experiment checking and analysis:
Illustrate below; Invent the validity of the three-dimensional Track In Track controller of AUV of design for checking; Emulation experiment is carried out in three-dimensional curve path to planning; And compare analysis with the traditional PID control simulation result: said according to step 1 in the summary of the invention, at first provide the position coordinates of desired track point
WP
1=(80,0,0),WP
2=(120,100,20),WP
3=(0,180,40),WP
4=(-120,100,60),
WP
5=(-80,0,80)
Provide AUV initial position, attitude initial value
x
0=90, y
0=-10, z
0=0, θ
0=0,
u
0=0, v
0=0, w
0=0, q
0=0, r
0=0 provides the design of Controller parameter
c
1=0.18,c
2=0.5,c
3=0.2,c
4=0.5,
p
3=1000,p
4=1000,c
5=10,c
6=10,k
u=0.1,k
1=1
Carry out controller according to summary of the invention step 2 of the present invention~6 then and resolve, flow process is as shown in Figure 3, and obtains simulation result.
Simulation analysis
Fig. 4~Figure 12 is the three-dimensional Track In Track simulation curve of AUV.For verifying the performance of the controller that the present invention designs; Compare with the simulation curve of PID controller the three-dimensional track points tracking Control of AUV; Fig. 4 is the three-dimensional Track In Track control of an AUV curve; Fig. 5 and Fig. 7 are respectively that the three-dimensional Track In Track curve corresponding with Fig. 3 schemed in the drop shadow curve of surface level and vertical plane, when perspective view partial enlarged drawing 6 can be found out the traditional PID controller controller to changing operate-point with Fig. 8, cause control performance to reduce, and can't realize the quick tracking to three-dimensional flight path; Controller based on the design of the contragradience method of feedback gain has robustness preferably to environmental disturbances; Improved the precision of Track In Track, shortened the redundant flight path of AUV, made itself and desired track more approaching; Fig. 9 is a tracking error curve in the three-dimensional Track In Track control of AUV, and the controller of this patent design has guaranteed higher tracking accuracy and response speed; Figure 10 and Figure 11 are respectively the change curve that each state variable in the three-dimensional Track In Track control procedure of AUV comprises linear velocity and attitude angle; Trim angle under the PID control action and bow have certain overshoot vibration to the angle variation; The adjusting time is longer; The control effect is relatively poor, causes system's unstability easily, and the controller that this paper proposes has more stable control ability to attitude angle; Figure 12 is the three-dimensional Track In Track control of AUV input response.