EP2107333A1 - Verfahren und System zur Steuerung eines sich in einer Flüssigkeit bewegenden Körpers - Google Patents
Verfahren und System zur Steuerung eines sich in einer Flüssigkeit bewegenden Körpers Download PDFInfo
- Publication number
- EP2107333A1 EP2107333A1 EP08425219A EP08425219A EP2107333A1 EP 2107333 A1 EP2107333 A1 EP 2107333A1 EP 08425219 A EP08425219 A EP 08425219A EP 08425219 A EP08425219 A EP 08425219A EP 2107333 A1 EP2107333 A1 EP 2107333A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- steering
- yaw
- pitch
- steering commands
- rotation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 36
- 239000012530 fluid Substances 0.000 title description 5
- 238000012795 verification Methods 0.000 claims abstract 2
- 238000004590 computer program Methods 0.000 claims 1
- 230000014509 gene expression Effects 0.000 description 11
- 241000251729 Elasmobranchii Species 0.000 description 3
- 230000002301 combined effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
- F42B19/00—Marine torpedoes, e.g. launched by surface vessels or submarines; Sea mines having self-propulsion means
- F42B19/01—Steering control
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
- B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
- B63G8/14—Control of attitude or depth
- B63G8/20—Steering equipment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
- B63H25/02—Initiating means for steering, for slowing down, otherwise than by use of propulsive elements, or for dynamic anchoring
- B63H25/04—Initiating means for steering, for slowing down, otherwise than by use of propulsive elements, or for dynamic anchoring automatic, e.g. reacting to compass
Definitions
- the present invention relates to a method and a system for steering a body moving, whether self-propelled, guided, or drawn, within a fluid; in particular, the following description will make explicit reference to an underwater vehicle, for example, a torpedo.
- Figure 1a is a schematic view of a steering system 1, of a known type, for controlling the movement of a body 2, for example, a torpedo having a cylindrical body with substantially circular cross section.
- the steering system 1 comprises four rudders 3, which define a pair of horizontal control surfaces 4a, arranged in the horizontal reference plane xy associated to the body 2 (defined by the longitudinal direction x and the transverse direction y), and a pair of vertical control surfaces 4b arranged in the vertical reference plane xz associated to the body 2 (defined by the longitudinal direction x and the vertical direction z).
- rudders 3 which define a pair of horizontal control surfaces 4a, arranged in the horizontal reference plane xy associated to the body 2 (defined by the longitudinal direction x and the transverse direction y), and a pair of vertical control surfaces 4b arranged in the vertical reference plane xz associated to the body 2 (defined by the longitudinal direction x and the vertical direction z).
- the control of the roll movement of the body 2 (represented by a roll momentum Mx about the longitudinal axis x) is achieved by means of a composition of the deflections of some or all of the horizontal and vertical control surfaces 4a, 4b.
- the first and second control loops acting respectively in the vertical reference plane xz and horizontal reference plane xy, can be considered at least partially free and hence operate according to logics defined specifically for each reference plane.
- FIG 1b shows a different steering system 1, of the type commonly known as "butterfly-rudder system".
- the four rudders 3 are in this case arranged to form a non-zero angle (for example, a 45° angle) with the transverse axis y and vertical axis z, and define control surfaces 5.
- the rudders 3 are arranged on mutually opposite sides, and in a position that is symmetrical with respect to the horizontal reference plane xy and vertical reference plane xz.
- the deflection of any one of the control surfaces 5 acts simultaneously on the horizontal reference plane xy (by means of the horizontal component Fy of the applied force F), the vertical reference plane xz (by means of the vertical component Fz of the applied force F) and the transverse reference plane yz (by means of the resultant roll momentum Mx) .
- torpedoes have control limitations, due to the small dimensions of the moving control surfaces, which are constrained by their necessary placement in the launching tubes (the cross section of the launching tubes limiting the maximum dimension of these surfaces), and moreover due to the wide dynamics of the speed of movement of torpedoes, which can go from low speeds (for example, for reducing the noise when approaching a target) to high speeds (for example, when reaching a target).
- This wide dynamics of the speed sets limitations on the control of the movement of torpedoes, given that, in a known way, the effectiveness of the moving control surfaces depends, among other elements, upon the speed of the moving body.
- a butterfly-rudder steering system proves to be more complex to implement in so far as it requires the definition of algorithms that take into account the combined effects that the deflection of each of the moving control surfaces has on the three reference planes, in order to determine the commands for the deflections to be imparted on the rudders according to the required movement.
- the aim of the present invention is consequently to provide a method and a system for steering a body in a fluid that will be optimized as regards the management of the moving control surfaces, in particular for bodies subject to structural limitations in the control of the movement.
- the present invention stems from the observation, by the Applicant, of the need, in steering systems subject to structural control limitations (for example, due to dimensional limitations of the moving control surfaces and/or to a wide dynamics of the speed of movement), to distribute in an optimized manner, on independent rudders, steering commands imparted simultaneously in the three reference planes.
- One aspect of the present invention consequently envisages the definition of an algorithm designed to distribute the commands for steering of the rudders, taking into account the limitations associated to the steering system, so as to obtain the desired behaviour during execution of the required manoeuvres, exploiting in an optimal manner the deflections that can be applied to each rudder.
- Figure 2 shows an underwater vehicle 10, in particular a self-propelled torpedo having control surfaces with small dimensions, provided with a steering system 11 designed to control submarine movement thereof.
- the steering system 11 comprises an arrangement 12 of rudders 13, including four rudders 13 in a "butterfly" arrangement (as described previously as regards Figure 1b ), each of which can be controlled individually for generating the rotation of the underwater vehicle 10 about a longitudinal axis x of its own (roll movement), a transverse axis y of its own (pitch movement), or a vertical axis z of its own (yaw movement).
- the rudders 13 are generally divided, on the basis of a position thereof with respect to the horizontal and transverse planes of symmetry of the underwater vehicle 10 considered in the direction of its movement, into: an upper-right (UR) rudder, an upper-left (UL) rudder, a lower-left (LL) rudder, and a lower-right (LR) rudder.
- UR upper-right
- UL upper-left
- LL lower-left
- LR lower-right
- the steering system 11 further comprises: actuator means 14, for example, provided with electric motors, operatively coupled to the rudders 13 for controlling deflection thereof; and a central control unit 15, connected to the actuator means 14 and provided with processing means (for example, microprocessor means), designed to execute appropriate software programs and instructions for controlling desired deflections of the rudders 13 through the actuator means 14.
- actuator means 14 for example, provided with electric motors, operatively coupled to the rudders 13 for controlling deflection thereof
- processing means for example, microprocessor means
- the central control unit 15 receives values of commanded trim (in terms of roll, pitch, yaw) in the three, horizontal, vertical, and transverse, reference planes for the movement of the underwater vehicle 10, from a wire-guide system (not illustrated) that connects the underwater vehicle 10 to a naval support vehicle (not illustrated), or else, in the absence of a wire-guide system (for example, in the process of homing towards a target), generates said values autonomously, according to an attack plan.
- the central control unit 15 On the basis of these commanded values and corresponding measurements made by sensors of the underwater vehicle 10, the central control unit 15 generates the commands for the deflections to be imparted on the rudders 13 for each of the three reference planes, which are considered independent.
- the simultaneous control in the three reference planes is obtained by summing algebraically for each of the four rudders 13 the deflections assigned for the control in the three reference planes. This is possible where the sum of the controlled deflections does not exceed for any rudder 13 a maximum applicable deflection.
- An aspect of the present invention consequently consists in configuring the central control unit 15 so as to process and modify the commanded deflections in order to determine, based on an optimized distribution algorithm, the commands for the optimal deflections to be imparted on each of the rudders 13.
- the distribution algorithm envisages, in an initial block 20, the reception (or autonomous generation) by the central control unit 15 of commanded deflections of roll ⁇ p, pitch ⁇ q and yaw ⁇ r, respectively for the rotation of the underwater vehicle 10 about the longitudinal axis x, the transverse axis y, and the vertical axis z.
- the controlled deflections are understood as being positive where they produce clockwise rotations about the respective axes of reference.
- a procedure of optimized distribution of the commanded deflections imparted on the four rudders 13 is then initiated, with the purpose of preventing any saturation that might bring the rudders 13 to an end-of-travel and of respecting a priority criterion of the commands to be executed in the reference planes.
- this priority criterion envisages, in the case where a total commanded deflection is greater than a value that would lead the rudders 13 to saturation, the definition of a priority in controlling some reference planes with respect to others, ensuring in any case a minimum deflection for each reference plane.
- a check is made to verify whether the sum of the commanded deflections of pitch ⁇ q and yaw ⁇ r, considered in absolute value, is less than a maximum deflection ⁇ max that can be made by the rudders 13 (without causing end-of-travel saturation), for example, equal to 20°.
- a comparison is made between the absolute value of the commanded deflection of yaw ⁇ r and a guaranteed minimum value of yaw ⁇ r min , for example, 5°.
- a check is made to verify whether the absolute value of the commanded deflection of pitch ⁇ q is lower than a guaranteed minimum value of pitch ⁇ q min , for example, 15°.
- the optimized distribution algorithm proceeds to block 27, where the residual band available for the control about the longitudinal axis x is determined.
- the distribution algorithm proceeds with the determination of the total deflections to be applied to the rudders 13, on the basis of the optimized values of the commanded deflections of yaw, pitch and roll ⁇ q, ⁇ r, ⁇ p, as determined previously.
- block 36 first a check is made on the value of the available residual deflection ⁇ .
- deflections to be applied to the rudders 13 for roll control are set to zero (block 37).
- the distribution algorithm envisages determination of two values of deflection for roll control (in this case both set to zero): a first value of roll control ⁇ p UR-LL to be applied to the upper-right (UR) rudder and lower-left (LL) rudder (which produce momenta of rotation in the same direction about the longitudinal axis x), and a second value of roll control ⁇ p LR-UL to be applied to the lower-right (LR) rudder and upper-left (UL) rudder (which produce momenta of rotation in the opposite direction about the longitudinal axis x).
- ⁇ UR , ⁇ LR , ⁇ LL and ⁇ UL are, respectively, the total deflections to be applied to the upper-right rudder, lower-right rudder, lower-left rudder and upper-left rudder (considered positive if they generate clockwise rotations about the longitudinal axis, evaluated in the direction of movement of the underwater vehicle 10).
- the deflections applied to at least three of the four rudders 13 are less than the maximum deflection ⁇ max so as to prevent any end-of-travel saturation of the same rudders, and consequent undesirable behaviour of the moving body.
- the distribution algorithm envisages the use of the available degree of freedom (given the presence of three steering commands applied to four rudders), to distribute the steering commands in an optimized manner.
- the algorithm proposed is particularly effective for control moving bodies having structural limitations of control (for example, due to dimensional and/or dynamic limitations of the moving control surfaces).
- the algorithm described can be modified for ensuring the guaranteed minimum value of yaw ⁇ r min or pitch ⁇ q min even in the case where it is subsequently necessary to perform a scaling of the commands for ensuring the roll control; for example, the operation of scaling (block 34) could regard only the controlled deflection of yaw ⁇ r, guaranteeing a value of the controlled deflection of pitch ⁇ q that is not less than the respective guaranteed minimum value of pitch ⁇ q min .
- the steering system 10 could envisage an arrangement of the rudders 13 different from the butterfly one described and illustrated so far, in which the rudders 13 are in any case independent and capable of generating rotations in the three reference planes.
- the guaranteed minimum values of yaw ⁇ r min and pitch ⁇ q min might not be constant and determined beforehand, but be variable and redefinible during execution of the control operations (for example, by the central control unit 15 or via commands received from the wire-guide system) so as to vary in real time the assignment of priority to the commands in the various reference planes.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Ocean & Marine Engineering (AREA)
- Aviation & Aerospace Engineering (AREA)
- Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE602008004737T DE602008004737D1 (de) | 2008-04-03 | 2008-04-03 | Verfahren und System zur Steuerung eines sich in einer Flüssigkeit bewegenden Körpers |
EP08425219A EP2107333B1 (de) | 2008-04-03 | 2008-04-03 | Verfahren und System zur Steuerung eines sich in einer Flüssigkeit bewegenden Körpers |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP08425219A EP2107333B1 (de) | 2008-04-03 | 2008-04-03 | Verfahren und System zur Steuerung eines sich in einer Flüssigkeit bewegenden Körpers |
Publications (2)
Publication Number | Publication Date |
---|---|
EP2107333A1 true EP2107333A1 (de) | 2009-10-07 |
EP2107333B1 EP2107333B1 (de) | 2011-01-26 |
Family
ID=39789526
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP08425219A Active EP2107333B1 (de) | 2008-04-03 | 2008-04-03 | Verfahren und System zur Steuerung eines sich in einer Flüssigkeit bewegenden Körpers |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP2107333B1 (de) |
DE (1) | DE602008004737D1 (de) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013173436A (ja) * | 2012-02-24 | 2013-09-05 | Mitsubishi Heavy Ind Ltd | 制御装置、制御装置の制御方法、および水中航走体 |
JP2016088348A (ja) * | 2014-11-06 | 2016-05-23 | 三菱重工業株式会社 | 舵制御装置、水中航走体及び舵制御方法 |
DE102016006933B3 (de) * | 2016-06-10 | 2017-11-16 | Thyssenkrupp Ag | Verfahren zur Kompensation der Blockade eines Ruderblattes in einem X-Ruder |
CN112591059A (zh) * | 2020-12-01 | 2021-04-02 | 中国科学院深圳先进技术研究院 | 水下航行器控制方法及装置 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3818853A (en) * | 1971-01-18 | 1974-06-25 | Ministre Defense Nat | Stop members in ships |
JPH06341852A (ja) * | 1993-06-01 | 1994-12-13 | Ishikawajima Harima Heavy Ind Co Ltd | 水中航走体及びその姿勢制御方法 |
GB2405125A (en) * | 2003-08-22 | 2005-02-23 | Ian Charles Holmes | Steering for coupled submersible vessels |
-
2008
- 2008-04-03 DE DE602008004737T patent/DE602008004737D1/de active Active
- 2008-04-03 EP EP08425219A patent/EP2107333B1/de active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3818853A (en) * | 1971-01-18 | 1974-06-25 | Ministre Defense Nat | Stop members in ships |
JPH06341852A (ja) * | 1993-06-01 | 1994-12-13 | Ishikawajima Harima Heavy Ind Co Ltd | 水中航走体及びその姿勢制御方法 |
GB2405125A (en) * | 2003-08-22 | 2005-02-23 | Ian Charles Holmes | Steering for coupled submersible vessels |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013173436A (ja) * | 2012-02-24 | 2013-09-05 | Mitsubishi Heavy Ind Ltd | 制御装置、制御装置の制御方法、および水中航走体 |
JP2016088348A (ja) * | 2014-11-06 | 2016-05-23 | 三菱重工業株式会社 | 舵制御装置、水中航走体及び舵制御方法 |
DE102016006933B3 (de) * | 2016-06-10 | 2017-11-16 | Thyssenkrupp Ag | Verfahren zur Kompensation der Blockade eines Ruderblattes in einem X-Ruder |
CN112591059A (zh) * | 2020-12-01 | 2021-04-02 | 中国科学院深圳先进技术研究院 | 水下航行器控制方法及装置 |
CN112591059B (zh) * | 2020-12-01 | 2022-02-08 | 中国科学院深圳先进技术研究院 | 水下航行器控制方法 |
Also Published As
Publication number | Publication date |
---|---|
EP2107333B1 (de) | 2011-01-26 |
DE602008004737D1 (de) | 2011-03-10 |
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