Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
  • B63B79/00—Monitoring properties or operating parameters of vessels in operation
  • B63B79/10—Monitoring properties or operating parameters of vessels in operation using sensors, e.g. pressure sensors, strain gauges or accelerometers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
  • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
  • B63H5/125—Arrangements on vessels of propulsion elements directly acting on water of propellers movably mounted with respect to hull, e.g. adjustable in direction, e.g. podded azimuthing thrusters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
  • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
  • B63H5/125—Arrangements on vessels of propulsion elements directly acting on water of propellers movably mounted with respect to hull, e.g. adjustable in direction, e.g. podded azimuthing thrusters
  • B63H5/1252—Arrangements on vessels of propulsion elements directly acting on water of propellers movably mounted with respect to hull, e.g. adjustable in direction, e.g. podded azimuthing thrusters the ability to move being conferred by gearing in transmission between prime mover and propeller and the propulsion unit being other than in a "Z" configuration
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B11/00—Measuring arrangements characterised by the use of optical techniques
  • G01B11/16—Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B17/00—Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations
  • G01B17/04—Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations for measuring the deformation in a solid, e.g. by vibrating string
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
  • G01L5/12—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring axial thrust in a rotary shaft, e.g. of propulsion plants
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
  • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
  • B63H5/125—Arrangements on vessels of propulsion elements directly acting on water of propellers movably mounted with respect to hull, e.g. adjustable in direction, e.g. podded azimuthing thrusters
  • B63H2005/1254—Podded azimuthing thrusters, i.e. podded thruster units arranged inboard for rotation about vertical axis
  • B63H2005/1258—Podded azimuthing thrusters, i.e. podded thruster units arranged inboard for rotation about vertical axis with electric power transmission to propellers, i.e. with integrated electric propeller motors

Definitions

• the present invention relates to a device and a method for determining the amplitude and direction of a force applied to a mechanical structure, in particular a boat propulsion boat, also known by the English name "propulsion oriented drive”. , or "POD”.
• boat in the context of the present description, we mean any type of motorized floating craft or boat intended for navigation.
• a boat may be equipped with one or more propulsion pods arranged partially in its hull and part of which is submerged.
• FIG. 1 illustrates a boat hull 1 comprising a boat propulsion pod 2 immersed in water, for example the sea (M).
• the propulsion nacelle 2 comprises a submerged mobile casing 3, a propulsion propeller 4 connected to the mobile casing 3 via a rotation shaft and an orientation device 5 placed in the hull of the boat.
• the mobile casing 3 carries a propulsion motor driving the propeller 4.
• the mobile casing 3 is connected to the orientation device 5 via a pivot link 6.
• the device 5 comprises a drive device enabling to orient the mobile casing 3, and thus to modify the propulsive direction of the propulsion propeller 4.
• the mobile housing 3 As the mobile housing 3 is immersed, it is subjected to stresses resulting in particular from shocks with floating solid bodies, such as icebergs in the case of an ice-breaking boat.
• shocks with floating solid bodies, such as icebergs in the case of an ice-breaking boat.
• it is necessary to estimate the damage suffered. In other words, it is necessary to estimate the characteristics of the shocks suffered by the propulsion platform. It is necessary for this purpose to know the direction of each shock and to estimate their amplitude.
• one solution consists in equipping the mobile casing with the propulsion nacelle of stress sensors.
• the stress sensors must cover the entire surface of the moving case.
• each sensor must be calibrated according to its position on the mobile housing.
• a method for determining the direction and amplitude of a force applied to a system comprising a fixed part and a deformable moving part under the effect of said force.
• mechanical deformations are applied to the moving part under the effect of said force by measuring a distance between the fixed part and the moving part in the direction of application of the force, and distance measurements are used to determine the magnitude and direction of the effort.
• the direction of the force is determined from the position of at least one measurement sensor delivering an extreme measurement value with respect to measurement values respectively provided by a set of sensors.
• measurement angularly distributed measuring the displacement of the movable portion relative to the fixed portion.
• the magnitude of the effort is determined from a set of predetermined distance measurements as a function of force values.
• the distance measurements vary linearly as a function of the values of effort.
• the method comprises a step of calculation by a finite element method.
• the method comprises a step of measurement of effort and displacement performed on a test bench.
• a device for determining the direction and amplitude of a force applied to a system comprising a fixed part and a deformable moving part under the effect of said force.
• the device comprises means for measuring the mechanical deformations of the mobile part, comprising distance measuring means between the mobile part and the fixed part, in the direction of application of the force and the means. processing devices capable of determining the amplitude and the direction of the effort from the measurements delivered by the measuring means.
• the measuring means comprise a set of measurement sensors angularly distributed around the moving part.
• the measurement sensors are mounted on a cylindrical portion of the fixed and movable parts.
• the processing means are adapted to determine the direction of the effort from the position of at least one sensor delivering an extreme measurement value with respect to the values provided by the other sensors.
• the processing means comprise storage means in which are stored a set of predetermined distance measurement values as a function of values. of efforts, the processing means being adapted to determine the amplitude of the effort from measurements delivered by the sensors.
• the storage means stores the direction and magnitude values of a force only if the magnitude value is greater than a threshold.
• the deformable and fixed parts are of cylindrical shape.
• a boat propulsion boat comprises a device for determining the direction and amplitude of a force on said boat as defined above.
• FIGS. 2 and 3 illustrate a propulsion boat equipped with a shock measuring device according to one embodiment of the invention, respectively in profile and from above;
• FIGS. 4 and 5 are side and top views of the propulsion nacelle of FIGS. 2 and 3, illustrating the behavior of the nacelle and its device for measuring shocks during an impact;
• FIG. 6 shows values measured by the sensors of deformation of the propulsion boat according to the time, during an impact
• FIG. 7 shows values measured by the deformation sensors of the propulsion boat according to their angular position during an impact.
• the propulsion boat which is mounted under the hull of the boat, comprises a movable part 12 internally comprising an electric motor driving a propeller h and a fixed part 13 fixed to the hull of the boat and to which the part is connected. movable 12 via a pivot connection 14.
• the movable portion 12 is adjustable relative to the fixed portion 13 about an axis of rotation A perpendicular to the longitudinal axis of the boat, preferably at a similar angle of revolution or equal to 1 80 °.
• a mark RI is attached to the fixed part 1 3 and a mark R2 is attached to the movable part 12.
• the pod 10 is mounted by the fixed part 1 3 under the hull of the boat so that the mobile part 12 extends to outside and be immersed to propel the boat. Shocks generated during navigation then apply to the movable part 12, and in particular, mainly on the front part, considering the direction of movement of the boat, and laterally.
• the movable part 12 comprises a movable casing 15 comprising a front bulb 15a, a tapered rear part 15b on which the propulsion propeller h is mounted and an intermediate attachment shaft 16, the axis of which coincides with the rotation axis A, ensuring the attachment of the movable portion 12 to the fixed portion 13 via the pivot connection 14.
• the pivot connection incorporates for this purpose a sealed bearing P passing through the hull of the boat and fixed to the fixed part 13.
• the fixed part 13 comprises a fixed casing 1 8 cylindrical installed in the hull of the boat and in which is placed an air diffuser 17 channeling a flow of cooling air to the onboard electric motor in the movable part 12.
• the air diffuser 17 is generally cylindrical. It comprises a base 17a solidarity of the fixing j 16, surmounted by an intermediate column 17b itself surmounted by a head 17c openwork.
• the diffuser including the base 17a and the intermediate column 17b, has an internal axial passage for conducting the cooling air to the engine.
• the base 17a comprises for this purpose internal fins for channeling the cooling air to the engine.
• the air diffuser 17 also ensures the guidance of electrical supply cables connected to the electric motor located in the propulsion platform 10 and driving the propeller h.
• the head 17c has in this respect an upper plate 17d resting on feet 17e in which run the power cables.
• the intermediate portion 17b comprises a cylindrical end 17f opposite the base 17a, of increased diameter.
• the assembly comprising the base 17a surmounted by the intermediate column 17b has a height H.
• the device I for determining the characteristics of the forces applying to the nacelle comprises a member 19 for measuring the mechanical deformation of the nacelle.
• the member 19 is particularly intended to measure the displacement of the movable portion 12 relative to the fixed portion 13 during the mechanical deformation of the nacelle.
• the device I also comprises a processing unit 11 able to determine the amplitude and the direction of the forces from the measurements delivered by the measuring member 19.
• the processing unit is made from a microprocessor. But it may be any device capable of determining the amplitude and the direction of the effort from the measurements delivered by the measuring member 19. It may be in particular a microcontroller.
• the measuring member 19 makes it possible to determine a distance D between the cylindrical end 17 f of the intermediate column 17b opposite the base 17a of the air diffuser 17 and the fixed casing 18 projected in a plane perpendicular to the axis AT.
• the measuring member 19 comprises a set of measurement sensors.
• the measuring member 19 comprises six sensors 19a, 19b, 19c, 19d, 19e and 19f all identical mounted on the fixed housing 18 and facing the Diffuser 17. They are advantageously positioned so as to point towards the cylindrical surface 17f.
• the sensors are mounted on a cylindrical portion of the fixed housing 18.
• the measurement sensors are for example non-contact sensors made from ultrasonic sensors. Alternatively, these sensors could be made from optical sensors.
• each sensor 19a, 19b, 19c, 19d, 19e and 19f measures a distance between the end of the cylindrical surface 17d opposite the pivot connection 14 and the fixed part 13 projected into a plane perpendicular to the axis of rotation (A) of the deformable portion 12 relative to the fixed portion 13.
• the measurement sensors 19a, 19b, 19c, 19d, 19e and 19f are angularly evenly distributed with respect to the axis A on a half-perimeter of the fixed casing 18 turned towards the propeller, as illustrated in FIG.
• the position of each measuring sensor is known and referenced.
• the air diffuser 17 and the fixed housing 18 are cylindrical, being mounted mobile in rotation relative to each other at an angular displacement of the order of 180 °, just equip a single half -perimeter of the strainer housing to measure the displacement of the diffuser 17 relative to the fixed housing 18, regardless of its angular position.
• the measuring member 19 comprises six measuring sensors 19a, 19b, 19c, 19d, 19e and 19f separated from each other by an angle of 30 ° with respect to the axis. AT.
• the processing unit 11 processes the measurements delivered by the measurement sensors to provide, in response, an indication of the state of the propulsion platform.
• the direction and the amplitude of the effort are determined by selecting the measurement sensor which delivers an extreme value.
• this sensor delivers an extreme value compared to other sensors.
• the direction of the effort is thus determined by the processing unit 11 from the identification of the sensor providing an extreme value.
• the value provided by the sensor is minimal.
• the measured distance value is maximum.
• the position of the selected sensor indicates the direction of application of the effort and the measured value allows to determine the magnitude of the effort as will be explained later.
• the processing unit 11 selects the two measurement sensors delivering the most extreme measured values.
• the position of the selected sensors indicates the direction of application of the force.
• the point of application of the effort lies in this case between the two selected sensors, and the values measured can determine the magnitude of the effort as will be explained later.
• the direction and the amplitude of the force are determined by identifying an extremum of a curve C1 connecting the values delivered by the sensors according to their angular position with respect to the axis. At a moment T.
• the curve C1 is substantially a horizontal line that has no extremum.
• the curve C1 When the force is applied at the same angle as the angle of implantation of a sensor, the curve C1 has an extremum which is minimum.
• the curve C1 When the force is applied in a direction corresponding to the angle of implantation of the sensor increased by 180 °, as can be seen in FIG. 4, the curve C1 has an extremum which is a maximum.
• the curve C1 connects the value of the extremum to the angular position of application of the force in the reference RI.
• the processing unit 11 samples at each instant T the values of the measurement sensors, determines the curve C1, identifies the extremum and deduces the direction of application of the effort.
• the sampling period T is for example equal to 5 ms.
• the value of the distance D is equal to a predetermined value d, for each measuring sensor.
• the amplitude of the force applied on the deformable part 12 is determined from data stored in memory in the processing unit 11 in the form of a correlation between the amplitude of the force applied and the value measured by each measuring sensor. This correlation corresponds to a response curve DR (FIG. binds the value of a force according to the value measured by each sensor.
• the response curve DR can take any form, in particular a linear, polynomial, parabolic form.
• response curve DR is of linear form.
• This straight line DR is established by raising a distance value measured by the measurement sensor when a force of known value is applied to the deformable portion 12.
• the known and measured values each form a point of the straight line DR defined by a pair of values of distance and effort. To determine a line-shaped response line, at least two pairs of values are required.
• the first pair of values is determined in the absence of force applied on the deformable part 12.
• the value of distance d is obtained.
• the second pair of values is determined by applying a force at the same angle as a measuring sensor of known amplitude on the deformable part 12.
• the straight line DR is identical for all the measuring sensors.
• pairs of values are determined, for example, by modeling and calculation by the known finite element method or by measurements of force and displacement carried out on the propulsion platform mounted on a test bench.
• the processing unit 11 associates for any value measured by a measurement sensor an amplitude of the effort by extrapolation of the response curve DR.
• the processing unit selects the measurement sensor having the extreme value with respect to the other values measured by the other sensors and calculates the amplitude of the force applied from the value provided by the selected measuring sensor and the curve DR response.
• the processing unit 11 calculates the amplitude of the effort applied by averaging the two amplitudes determined from values measured by the two sensors and the response curve DR.
• the accuracy of the determination of the amplitude of a force can be improved by determining a quadratic form of the DR response line from a number of pairs of values greater than two.
• FIGS. 4 and 5 which illustrate the device I when the nacelle is subjected to a force F at a time Te.
• the force F is here oriented at 270 ° in the trigonometric direction with respect to the axis (A) and of amplitude F.
• the force F is applied at the same angle increased by 180 ° along the axis (A) that the measuring sensor 19c.
• the force F is applied to an impact point located at a distance L with respect to the end of the air diffuser 17 in contact with the attachment leg 16.
• the moving part of the propulsion platform 10 Under the impact of the force F, the moving part of the propulsion platform 10 is deformed relative to the fixed part. As in the direction of impact the movable 12 and fixed parts 13 are secured, the force F exerts a torsion moment M on the fastening leg 16 at the point P of the axis of rotation (A) between the fixed parts and mobile, whose value is equal to F * L.
• the attachment leg 16 is deformed under the effect of the moment M. The greater the distance L, the more the deformation of the attachment leg 16 is amplified.
• the housing 15 thus amplifies on the length L the effects of a force applied on the deformable part 12.
• the diffuser 17 being secured to the attachment leg 16 which is deformed in the direction of impact, it moves in the opposite direction of the shock F, so that the point P constitutes a pivot for the deformable part subjected to a force.
• the amplitude of the displacement of the diffuser 17 is, as previously explained, amplified according to its height H.
• the measurement sensors 19a, 19b, 19c, 19d, 19e and 19f measure the displacement amplified by the height H of the diffuser 17.
• FIG. 6 shows the evolution of the distances measured by the six measurement sensors 19a, 19b, 19c, 19d, 19e and 19f as a function of time t.
• the distances D19a, D19b, D19c, D19d, D19e and D19f measured by the seven sensors are all equal to d.
• the value of the distance D19c measured by the sensor 19d which coincides with the direction of the force applied to the nacelle, has a peak amplitude of.
• Sensors 19a, 19b, 19d, 19e and 19f measure different distances, here lower.
• FIG. 7 shows the evolution of the distances measured by the six measurement sensors 19a, 19b, 19c, 19d, 19e and 19f as a function of their respective angular position at the instant Te of the impact.
• the measuring sensor 19c is at the 0 ° angular position when the mobile casing 15 is in free-road operating condition, that is to say when the mobile part 12 is aligned with the fixed part 13 as represented in FIG. figure 3.
• the curve C1 has a maximum amplitude measured at the angular position a with respect to the axis (A) located between the sensors 19b and 19c.
• the processing unit 11 filters and determines from the measured values the measurement sensors 19 and the response curve DR determined previously, according to the measured amplitude peaks, the torsion moment M, the amplitude of the shock, the direction of the shock in the reference RI then projects the direction of the shock in the R2 mark. Depending on the orientation of the propulsion boat 10, the marks RI and R2 do not coincide.
• the amplitude and direction of the shock values in the reference mark of the boat and the propulsion pod are stored in memory by the processing unit 1 1 as a function of time.
• the processing unit 1 1 saves the characteristics of a shock only if the amplitude value of the shock is greater than a predefined value, in other words the value of direction of the shock. and the value of the corresponding amplitude are stored only if the amplitude value is greater than a threshold. This selective memorization of the characteristics of a shock makes it possible to rapidly analyze the shocks damaging the platform 10 to determine when to carry out the maintenance operations.
• the processing unit 1 1 comprises a screen for displaying the amplitude and direction of the shock in real time and the values saved.
• the saved data make it possible to reconstruct the shock history and thus plan the preventive maintenance steps of the propulsion nacelle 1 0, for example by comparing the measured and calculated characteristics with threshold values.
• the embodiment of the method described determines the direction and the amplitude of the shock in a simple manner, requiring few sensors and a single calibration step of the measuring member.
• This embodiment can be easily transposed to the study of a force applied to the nacelle not permanently. It suffices that the processing unit and the measuring device have a sufficient resolution enabling a variation in amplitude to be detected when a force is applied to the nacelle.

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• 2017
  • 2017-07-11 EP EP17305905.6A patent/EP3428055B1/de active Active
• 2018
  • 2018-07-10 RU RU2020106131A patent/RU2770255C2/ru active
  • 2018-07-10 CN CN201880045574.7A patent/CN110914147B/zh active Active
  • 2018-07-10 EP EP18735610.0A patent/EP3652065A1/de not_active Withdrawn
  • 2018-07-10 US US16/630,418 patent/US20210114699A1/en active Pending
  • 2018-07-10 WO PCT/EP2018/068689 patent/WO2019011927A1/fr unknown
  • 2018-07-10 KR KR1020197038725A patent/KR102558717B1/ko active IP Right Grant

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