GB2036318A - Navigational aid - Google Patents

Abstract

Berthing data display means comprise two identical displays D separately mounted on a jetty J. The displays D respectively display bow and stern berthing data in respect of a ship S during a berthing operation, and they are positioned to present the data on the lines of sight LB and LS to a pilot on the bridge B of the ship S. Each display D comprises a large fascia panel providing a two-digit display of the bow or stern distance- off. Mounted above the two-digit display of distance-off is a row of three velocity-range indicator elements in the form of green, amber and red circular lamps. Steady illumination of the green lamp indicates a safe approach velocity; flashing of the amber lamp indicates an excessive but marginally safe approach speed; and flashing of the red lamp indicates that the approach speed is within a dangerously high range. <IMAGE>

Description

SPECIFICATION Navigation aid This invention relates to navigation aids of the type which determine berthing data to assist the pilot of a ship during a berthing operation, and in particular to display means for visually displaying the determined data.

Such aids are in use to provide pilots, particularly the pilots of large ships such as supertankers and bulk ore carriers, with information as to the angle or "attitude" of the ship with respect to the jetty, the distance of the ship therefrom, and the speed of approach.

Installations are in use which provide a visual display of this data on the jetty within sight of the pilot, one such installation being described in our Patent Specification No. 1 ,384,647, although alternatively the data may be transmitted by radio or microwave link to the pilot on board ship. The berthing data is derived from measuring devices using sonar, microwave, acoustic, laster or other techniques, which detect the distance from the jetty of respective bow and stern sections of the ship, normally referred to as the "fore and aft distance off" measured at bow and stern fenders on the jetty. Although such installations in generai perform very satisfactorily problems have been encountered in the presentation of the berthing data to the pilot on board the ship in an optimum manner.

Frequency spectrum pollution is reducing the effectiveness of VHF shore to ship voice transmissions, and microwave links, as used to transmit berthing data to the pilot. A method of presentation is required which will ensure the continuous availability of berthing information to the bridge and which will not interfere with vital radio or microwave transmissions. This requirement has led to visual analogue displays of clock dial types and others which display speed of approach and distance-off for bow and stern as four separate digital displays. These types of display have a poor assimilation factor from the pilots' viewpoint.

The object of the invention is to provide display means which provide a visual berthing display capable of providing, in one integrated format, the distance-off and speed of approach information in a novel manner capable of rapid assimilation by the pilot of a ship being berthed.

To this end, according to the invention, berthing data display means for mounting on a jetty comprise an integrated format comprising distance data elements operative for digital display of distance-off and a plurality of velocity indicators which are independently operative to indicate respective ranges of speed of approach.

The display means may display the distance-off and speed of approach of only one section of the ship, so that a complete berthing installation will include two such means respectively providing bow and stern berthing data. Alternatively the means may provide a combined visual display of both bow and stern berthing data, and in this case the bow and stern sections of the display may be disposed virtically one above the other, or horizontally side by side.

Preferably three speed of approach ranges are indicated, and the velocity indicators may comprise lights which occult at pre-set velocity limits. Thus a green light may indicate a safe speed of approach, determined by the fender and jetty design criteria, an amber light may indicate an excessive but marginally safe speed range, and a red light indicate a dangerous speed range. A driving circuit controlling the display may operate to provide the green light 'ON' and continuously illuminated when the speed is within the permitted design limits, with the amber and red lights flashing on and off when the ship is within the excessive and dangerous speed range limits respectively.This "traffic light" format of three lights associated with a large size illuminated digital indication of distance-off in one integrated display is capable of more rapid and accurate assimilation by a pilot than has been the case with the analogue or digital displays previously available.

Directional signs may be incorporated, indicating the direction of movement of the ship either towards or receding from the jetty. An alpha-numeric display may be employed which can display coded letters or shapes as well as the distance-off digits. The display means may be rotatably mounted to permit adjustment of sight lines to suit the different geometry of ship approaches. The speed of approach may also be displayed digitally, in addition to the independently operative velocity indicators of the invention.

Several embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a ship and jetty during a berthing operation, employing a navigation aid installation which provides separate visual displays of bow and stern berthing data; Figure 2 similarly shows a combined visual display of bow and stern berthing data; Figures 3, 4 and 5 show alternative display means for use in the installation of Figure 1; Figure 6 is a system schematic illustrating such means and an associated interface unit/driver circuit; Figures 7, 8 and 9 show alternative display means for use in the installation of Figure 2; and Figure 10 illustrates a typical light module of the foregoing display means.

Figures 1 and 2 show a ship S berthing at a pier jetty J. In each case the berthing aid installation determines, by known means not illustrated and which form no part of the invention, appropriate berthing data relating to the bow and stern sections of the ship S. In Figure 1 the bow and stern data are respectively separately displayed by identical display means D mounted on the jetty J.

They are positioned to present a visual display on the line of sight LB or Ls of the pilot on the bridge B of the ship S. Each display means D is a free standing display structure including a rotary mounting to permit adjustment of the sight lines LB and L5 to suit different geometry of ship approaches.

The installation of Figure 2 employs display means D' in the form of a single unit providing a combined bow and stern berthing data display in the single line of sight L' of the pilot.

Return-ing now to the installation of Figure 1, one of the display units D of that figure is illustrated in more detail in Figure 3. The large fascia panel 1 which is of weather-resistant plastics material mounts two seven element large digit displays 2 and 3 providing a two-digit display of the bow distance-off. Each of the seven display elements such as 4 and 5 is a discrete lamp unit, for example employing quick-start fluorescent tubes or fibre-optic light guides from a lighting module as later described with reference to Figure 10. When all seven elements of the displays 2 and 3 are illuminated the distance-off displayed is 88 as shown in Figure 3, the displays 99 being illustrated in Figure 1.This arrangement allows display of distances up to 99, which may be calibrated for example in metres or yards, and it will be appreciated that the number of display digits can be increased to accomodate greater distances -three will allow display up to 999, and four will display up to 9999, etc.

Mounted above the two-digit display of distance-off on the fascia 1 is a row of three velocity-range indicator elements in the form of circular lights 6, 7 and 8. The light 6 is green and a steady illumination thereof indicates that the velocity is within a safe range. The light 7 is amber and when operative is intermittently illuminated, a flashing amber signal indicating'an excessive but marginally safe speed range for berthing. The light 8 is red and flashing thereof indicates a dangerously high speed range.

The alternative display unit D of Figure 4 includes all the elements of Figure 3, indicated by the same reference numerals, and additionally displays the direction of ship approach in the form of two arrows 9 and 10. The arrow 9 is illuminated to indicate that the ship S is approaching the jetty .J; the arrow 10 is alternatively illuminated to indicate that the ship S is receding from the jetty .J.

Figure 5 illustrates another form of the unit D, the three lights 6, 7 and 8 again providing a "traffic light" display of speed of approach ranges which can be preset in any ranges within a total range which is typically 0 to 99 cm/sec. In this case the two-digit distance-off display is provided by alpha-numeric elements each employing a 7x5 dot matrix of flameproof lamp enclosures. These are shown as driven to display the distance "1 7", and it will be appreciated that they can also be used to display other coded information.

The system schematic of Figure 6 shows the display unit D of Figures 1 and 3 and associated interface unit/driver circuit 13. The unit 13 interfaces with the range/velocity measuring device which as mentioned may be of any known type employing sonar, radar, acoustic, laser or other techniques. The unit 13 is supplied with speed and distance input signals at 14 and 1 5 and outputs at 1 6 to 19 respectively speed, direction, distance and switching signals appropriate to the unit D. This interface control unit 13 acts as a digitiser and will accept ship's speed and distance data in analogue or digital form.A signal conditioning circuit, an analogue to digital converter, counters and coincidence circuits can all be provided in the unit 13 dependent upon the form of the input data at 14 and 15, from whatever measurement source it is derived. DCD converters and/or decoders which by themselves possess no novelty illuminate the distance digits 2 and 3 corresponding to the input data; cbntrol signals out activate the velocity lights 6, 7 and 8 and the directional signs 9 and 10 when provided.

Figures 7, 8 and 9 diagrammatically illustrate alternative display units D' for the combined single bow and stern display of the Figure 2 installation.

In each case the fascia of the unit has two sections 1 a and 1 b respectively displaying berthing data relating to bow and stern of the ship S. The display elements mounted on the section 1 a of Figure 7 are identical in form and arrangement with those of Figure 3, and the same reference numerals are used for like elements. In this figure the fascia section 1 b mounts a mirror image arrangement of the same display elements, i.e. the velocity range indicator elements 6, 7 and 8 are mounted below the distance display digits 2 and 3.

The alternative arrangements of Figures 8 and 9 display the bow and stern data side by side. In Figure 8 the velocity range indicator elements 6, 7 and 8 are in each section 1 a or 1 b disposed vertically adjacent the corresponding outer side edge of the fascia. The continuous green indicator light 6 is at the bottom and the flashing red indicator light 8 at the top, i.e. a conventional vertical traffic light colour arrangement.

Figure 9 shows an arrangement which employs a horizontal display, in this case the velocity range indicator elements 6, 7 and 8 being disposed at the bottom of the corresponding section 1 a or 1 b as in the stern section 16 of Figure 7, but now the bow and stern sections 1 a and 1 b are disposed side by side. In addition to a three-digit distance off display 20, 21, 22 each section 1 a or 1 b has a two-digit digital speed of approach display 23,24 mounted alongside and to the right of the digital distance-off display 20, 21, 22. These two digital displays 20, 21,22 and 23,24 are disposed above the row of three spaced range indicator elements 6, 7 and 8.

Figure 10 illustrates a typical flameproof display lighting module as fitted in the unit D or D' behind the fascia 1. A flameproof enclosure 25 houses a mains transformer 26, a tungstenhalogen light source 27 and an intervening switching circuit 27. A mains supply cable 29 enters through a sealing gland 30, an ON/OFF signal lead 31 from the interface control unit 13 enters through a sealing gland 32, and a bundle of fibre-optic light guides 33 from the light source 27 leave the enclosure 25 through a further sealing gland 34. The fibre-optic guides 33 lead to the corresponding display element on the fascia 1, in Figure 10 one of the vertical digit elements such as 4 being shown.

Claims (20)

1. Berthing data display means for mounting on a jetty, comprising an integrated format comprising distance data elements operative for digital display of distance off, and a plurality of velocity indicators which are independently operative to indicate respective ranges of speed of approach.

2. Berthing data display means according to claim 1, wherein said means provide a combined visual display of both bow and stern berthing data relating to distance-off and speed of approach.

3. Berthing data display means according to claim 2, wherein bow and stern sections of the display are disposed vertically one above the other.

4. Berthing date display means according to claim 2, wherein bow and stern sections of the display are disposed horizontally side by side.

5. Berthing data display means according to any one of the preceding claims, wherein said format additionally comprises velocity data elements operative for digital display of speed of approach.

6. Berthing data display means according to any one of the preceding claims, wherein said velocity indicators are operative to indicate three speed of approach ranges.

7. Berthing data display means according to claim 6, wherein said velocity indicators comprise lights which occult at pre-set velocity limits.

8. Berthing data display means according to claim 7, wherein said lights comprise a green light which indicates a safe speed of approach, an amber light which indicates an excessive but marginally safe speed range, and a red light which indicates a dangerous speed range.

9. Berthing data display means according to claim 8, associated with a driving circuit to control the display and which is operative to provide the green light 'ON' and continuously illuminated when the speed of approach is within permitted design limits, and to control the amber and red lights so that they respectively flash 'ON' and 'OFF' when the ship is within the excessive and dangerous speed range limits respectively.

10. Berthing data display means according to any one of the preceding claims, wherein said plurality of velocity indicators are arranged in a horizontal row, either above or below the digital display of distance-off.

11. Berthing data display means according to any one of claims 1 to 9, wherein said plurality of velocity indicators are arranged in a vertical row to one side of the digital display of distance-off.

12. Berthing data display means according to any one of the preceding claims, wherein directional signs are incorporated which indicate the direction of movement of a ship either towards or receding from the jetty.

13. Berthing data display means according to any one of the preceding claims, wherein an alpha-numeric display is employed which can display coded letters or shapes as well as the distance-off digits.

14. Berthing data display means according to any one of claims 1 to 12, wherein the digital display of distance-off employs, for each digit thereof, seven display elements each of which is a discrete lamp unit employing quick-start fluorescent tubes or fibre-optic light guides from a lighting module.

1 5. Berthing data display means according to any one of the preceding claims and constructed as a free-standing display-structure including rotary mounting means to permit adjustment of sight lines to suit a different geometry of ship approach.

1 6. A berthing installation employing berthing data display means according to any one of the preceding claims.

1 7. A berthing installation according to claims 1 and 2, wherein said display means is one of two such display means which respectively display bow and stern berthing data.

1 8. Berthing data display means constructed and arranged substantially as herein particularly described with reference to any one of Figures 3 to 10 of the accompanying drawings.

19. A berthing installation constructed and arranged substantially as herein particularly described with reference to Figure 1, or as modified to include display means as described with reference to any one of Figures 3 to 6, of the accompanying drawings.

20. A berthing installation constructed and arranged substantially as herein particularly described with reference to Figure 2, or as modified to include display means as described with reference to any one of Figures 7 to 9, of the accompanying drawings.