Method of control of ship traffic

FIELD: water transport; control of ship motion to reference point in preset direction.

SUBSTANCE: proposed method consists in forming signal of deflection from preset trajectory which is fed together with course error signal and course derivative to input of rudder actuating mechanism. Besides that, use is made of reference point in preset direction and two signals of deflection from preset trajectory are formed; the first signal is determined as algebraic difference between present magnitude of ship's bearing to reference point П_ref.p. and present course K; the second signal is determined as algebraic difference between preset course to reference point K_pr. and present course K; then, combination of these signals and course derivative signal ω are fed to rudder actuating mechanism input by the following formula: δ=a₁(П_ref.p.-K)+a₂ω+a₃(K_pr.-K), where a₁, a₂, a₃ are gain coefficients of respective signals.

EFFECT: enhanced accuracy of ship's motion to reference point in preset direction.

3 cl, 4 dwg

The invention relates to water transport for the movement control of the vessel in the exercise of its output in arbitrary point in a given direction.

There are various ways to control the movement of the vessel along a given trajectory, which consists in forming a signal proportional to the deviation from the target path, and submit it together with the signals of the error rate and its derivative at the input of the Executive steering mechanism (SU 1066896, B63H 25/24; SU 1102714, B63H 25/00; SU 1618700, B63H 25/00).

The disadvantages of these methods are:

- no possibility of continuous control of the position of the vessel on the desired trajectory due to the heterogeneity of the form path (alternating straight and curved sections);

- the use of quite a large number of calculated parameter values to determine the error signal based on the angular velocity and the deviation from the desired trajectory, resulting in a significantly reduced accuracy of the hold of the vessel on the desired trajectory, which is unacceptable in the implementation of output in arbitrary point in a given direction;

- removed the ability to achieve the main goal of the maneuver is output in arbitrary point in a given direction in the absence of a fixed center of rotation in the area of maneuver.

The closest to offe the WMD method is a method of controlling the trajectory of the vessel, consisting of the signal deviations from the desired trajectory and submitting it together with the signals of the error rate and its derivative at the input of the Executive steering mechanism (Yakushenko A.A. and other New technical means of navigation. - M.: Transport, 1973, p.205, 242). The method has all the drawbacks listed above.

The technical result, which is aimed by the invention is to improve the precision motion control of the vessel to exit the conditional point in a given direction.

To achieve the technical result of the proposed method lies in the formation of signal deviations from the desired trajectory, submitting it together with the signals of the error rate and the derivative at the exchange rate at the input of the Executive steering mechanism, in addition use a conditional point in a given direction, forming two signal deviations from the target path, the first signal is defined as the algebraic difference between the current value of the bearing from the vessel to the conditional point (P_ut) and the current value of the ship's course (J), the second signal deviation is defined as the algebraic difference between the specified direction of the vessel on a notional point (K_ZV) and the current value of the ship's course (J), and the input of the Executive steering mechanism p which give a combination of these signals and the signal derived at the rate of (ω ) by the formula:

σ=a₁(P_ut-To)+a₂ω+a₃(K_ZV-To),

where a₁, a₂and₃the gain on the corresponding signals.

In addition, if not visually observed conditional point in a given direction is the bearing from the vessel to the conditional point calculated by the formula:

P_ut=arctan {[(λ_ut-λ)cosϕ]/(ϕ_ut-ϕ)},

where λ_utthat λ - longitude imaginary point and the longitude of the location of the vessel, respectively;

ϕ_utthat ϕ latitude conditional point and the latitude of the location of the vessel, respectively.

As a conditional use point buoy mooring barrel, loading device, etc.

Distinctive features of the proposed method from the above known and which is the closest are using an imaginary point in a given direction, the formation of two signals, the first of which is defined as the algebraic difference between the current value of the bearing from the vessel to the conditional point (P_ut) and the current value of the ship's course (J), the second signal deviation is defined as the algebraic difference between the specified direction of the vessel on a notional point (K_ZV) and the current value of the ship's course (J), and the input of the Executive steering mechanism serves a combination which these signals and the signal derived at the rate of (ω ) by the formula:

σ=a₁(P_ut-To)+a₂ω+a₃(K_ZV-To),

where a₁and₂and₃the gain on the corresponding signals.

In addition, if not visually observed conditional point in a given direction is the bearing from the vessel to the conditional point calculated by the formula:

P_ut=arctan{[(λ_ut-λ)cosϕ]/(ϕ_ut-ϕ)},

where λ_utthat λ - longitude imaginary point and the longitude of the location of the vessel, respectively;

ϕ_utthat ϕ latitude conditional point and the latitude of the location of the vessel, respectively.

The proposed method is illustrated in the drawings, figure 1-4.

Figure 1-4 shows the major variants of possible positions of the vessel relative to the conventional point for a given direction of its output in it, and in this case K_ZV=180°.

During the movement of the vessel from its original position(1; 2; 3; 4), as shown in figure 1-4, in a conventional point (buoy, mooring barrel, loading device and the like) is continuously carried out measurements of the ship's course (J), bearing on a notional point (P_ut) and the angular velocity of the ship (ω) or, equivalently, the derivative of the course. If the conditional point is the underwater object and cannot be observed visually, is bearing P_utraschityvat the t according to the formula:

P_ut=arctan{[(λ_ut-λ)cosϕ]/(ϕ_ut-ϕ)},

where λ_utthat λ - longitude imaginary point and the longitude of the location of the vessel, respectively;

ϕ_utthat ϕ latitude conditional point and the latitude of the location of the vessel, respectively.

Coordinates at the point of, if it is fixed, are fixed values, and the coordinates of the vessel are variable parameters and measure them in a continuous mode using a ship diamondcutter satellite navigation system (SNS) GPS or the same system, but with the use of differential corrections DGPS with high positional accuracy (±1.0 m).

Signals a deviation from the target trajectory (in this case two of them) form as follows.

The magnitude and sign of the 1st signal is defined as the algebraic difference between the current value of the bearing from the vessel to the conventional point of P_utand the current value of the ship's course K. the Magnitude and sign of the 2nd signal is defined as the algebraic difference between the specified direction of the vessel in a conventional point To_ZVand the current course of the vessel K.

Motion control of the vessel to exit the conditional point in a given direction, the proposed method implemented by applying to the input of the Executive steering mechanism, the combination of signals (N_ut-To), É , (K_ZV-To).

The law of steering the vessel is realized in the form

where a₁, a₂and₃the gain on the corresponding signals.

The rudder angle α_rhas the sign opposite to the sign of the value determined by the dependence (2), i.e.,

In the expression (3) W is the transfer function of the actuator.

The proposed method for motion control of the ship to carry out its output in arbitrary point in a given direction does not preclude mobility imaginary point on the plane, but to achieve the goal in question maneuver in this case it is necessary to impose restrictions in the ratio of linear speed of the ship υ and the linear speed of the conditional point υ_uttaking into account their relative position at the beginning of rapprochement. So, for example, to exit the vessel in fluid conditional point in a given direction from the source positions 1, 2 (see figure 1, 2) requires that the specified speed ratio to satisfy the condition υ_ym/υ less than 1.0.

As a result of application of the present invention is achieved by the possibility of obtaining a technical result - improvement of the accuracy of the vessel in a conditional point in a given direction, thus, the proposed method of control the movement the of the vessel meets the criteria of patentability "industrial applicability".

1. The method of controlling the movement of the vessel, which consists in the formation of signal deviations from the desired trajectory, submitting it together with the signals of the error rate and its derivative at the exchange rate at the input of the Executive steering mechanism, characterized in that it further conditional use point in a given direction, forming two signal deviations from the target path, the first signal is defined as the algebraic difference between the current value of the bearing from the vessel to the conditional point (P_ut) and the current value rate (K), the second signal deviation is defined as the algebraic difference between the specified direction of the vessel on a notional point (K_ZV) and the current ship's course (J), and the input of the Executive steering mechanism serves a combination of these signals and the signal derived at the rate of (ω) by the formula

σ=a₁(P_ut-To)+a₂ω+a₃(K_ZV-To),

where a₁, a₂and₃the gain on the corresponding signals.

2. The method according to claim 1, characterized in that, if not visually observed conditional point in a given direction is the bearing from the vessel to the conditional point calculated by the formula:

P_ut=arctan {[(λ_ut-λ)cosϕ]/(ϕ_ut-ϕ)},

where λ_utthat λ - the longitude of the point of the longitude location of the vessel, respectively;

ϕ_utthat ϕ latitude conditional point and the latitude of the location of the vessel, respectively.

3. The method according to claim 1, characterized in that as a conditional use point buoy mooring barrel or loading device.