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`EX. PGS 1005
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`United States Patent [19J
`Ambs et al.
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`111111
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`1111111111111111111111111111111111111111111111111111111111111
`US0060117 52A
`[11] Patent Number:
`[45] Date of Patent:
`
`6,011,752
`Jan.4,2000
`
`[54] SEISMIC STREAMER POSITION CONTROL
`MODULE
`
`4,694,435
`5,443,027
`
`9/1987 Magnesville .............................. 367/17
`8/1995 Owsley eta!. .......................... 114/244
`
`[75]
`
`Inventors: Loran D. Ambs, Fulshear; Ronald E.
`Chambers, Houston, both of Tex.
`
`[73] Assignee: Western Atlas International, Inc.,
`Houston, Tex.
`
`Primary Examiner-Christine K. Oda
`Assistant Examiner-Anthony Jolly
`
`[57]
`
`ABSTRACT
`
`[21] Appl. No.: 09/128,336
`
`[22] Filed:
`
`Aug. 3, 1998
`
`Int. Cl? ....................................................... GOlV l/00
`[51]
`[52] U.S. Cl. ............................ 367/17; 114/235; 114/244;
`114/242
`[58] Field of Search ........................ 367/61, 17; 181!110;
`340/7; 114/235, 244, 242
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`A seismic streamer position control module has been
`invented having a body with a first end and a second end and
`a bore therethrough from the first end to the second end for
`receiving a seismic streamer therethrough, at least one
`control surface, and at least one recess in which is initially
`disposed the at least one control surface, the at least one
`control surface movably connected to the body for move(cid:173)
`ment from and into the at least one recess and for movement,
`when extended from the body, for attitude adjustment. In one
`aspect the seismic streamer position control module body
`has tapered ends.
`
`3,943,483
`
`3/1976 Strange ................................... 114/235
`
`20 Claims, 5 Drawing Sheets
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`26 28
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`20
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`14
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`Ex. PGS 1005
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`U.S. Patent
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`Jan.4,2000
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`Sheet 1 of 5
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`6,011,752
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`Fig. 1
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`Fig. 2
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`Fig. 3A
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`Fig. 3B
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`26 28
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`20
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`14 ..... '
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`'-30
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`Ex. PGS 1005
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`U.S. Patent
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`Jan.4,2000
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`Sheet 2 of 5
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`6,011,752
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`54
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`so-......_
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`56 58
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`61
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`4F _j
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`56 58
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`Fig. 4A
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`56
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`51
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`51
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`11_) l
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`fl 60
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`,, <
`~----s
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`-
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`,-so 58
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`52
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`58
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`61
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`Fig. 4B
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`Ex. PGS 1005
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`U.S. Patent
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`Jan.4,2000
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`Sheet 3 of 5
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`Fig. 4C
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`52
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`68
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`62_./
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`59
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`56
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`Fig. 4E 52
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`Ex. PGS 1005
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`U.S. Patent
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`Jan.4,2000
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`Sheet 4 of 5
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`6,011,752
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`Fig. 4F
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`68
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`Fig. 5
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`<!>2
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`Fig. 6A
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`-1---l---~n
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`Fig. 6B
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`Ex. PGS 1005
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`U.S. Patent
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`Jan.4,2000
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`Sheet 5 of 5
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`6,011,752
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`r--------------------------------------------------,
`1 STREAMER ELECTRONICS
`l I STREAMER CONTROL SIGNALS I I STREAMER POWER : :
`I
`L--------1-------------------------------
`PROGRAMED DEPTH
`MOVE LEFT I RIGHT
`
`I
`_________ _j
`
`1
`I
`
`I
`
`-~ FUZZY LOGIC CONTROL
`
`WING AXIS ROTATOR I
`
`I
`
`STREAMER POSITION
`CONTROL MODULE
`ROLL SENSOR
`
`DEPTH
`SENSOR
`
`I
`
`WING
`ANGLE-OF-ATTACK
`SENSOR
`
`Fig. 7
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`Ex. PGS 1005
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`6,011,752
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`1
`SEISMIC STREAMER POSITION CONTROL
`MODULE
`
`BACKGROUND OF THE INVENTION
`
`2
`devices in order to adjust the position and shape of the
`streamer cable, or order a vessel's helmsman to redirect the
`vessel, or suspend data acquisition.
`In certain prior art systems, a bird is about four feet long
`5 and is powered by multiple D-size batteries. Rechargeable
`batteries have been employed in some birds to extend the life
`of the batteries. Electric power in some devices is ineffi(cid:173)
`ciently transmitted to the bird via electromagnetic induction
`coils beneath the skin of the streamer and a coil in the bird.
`10 These birds must be removed from a streamer as it is
`retrieved and secured to the streamer as it is deployed.
`Communication between the ship-board streamer controller
`and the birds is accomplished via signals communicated at
`relative low data rates across the skin of the streamer by
`15 indirect means of one or more electromagnetic coils beneath
`the skin of the streamer and another coil within the bird
`structure. Elaborate mechanical schemes have been devised
`to assure communications as the streamer cable rotates
`relative to the bird.
`There has long been a need for an easily deployable and
`retrievable seismic streamer whose depth can be controlled.
`There has long been a need for such a streamer with effective
`and efficient depth control devices. There has long been a
`need for a seismic streamer depth control device whose
`25 power is effectively and efficiently obtained from a streamer
`power distribution system. There has long been a need for a
`simple way to communicate directly with a bird's control
`and sensor electronics. There has long been a need for a bird
`device which is also capable of producing vertical, non-
`3D vertical, and horizontal forces which facilitate vertical and
`horizontal movement of the streamer cable. There has long
`been a need, recognized by the present inventors, for rela(cid:173)
`tively compact bird devices that do not interfere with
`streamer deployment and retrieval operations and which, in
`35 certain aspects, remain on a streamer in storage.
`
`1. Field of the Invention
`This invention is directed to seismic streamers; to seismic
`streamer depth control devices; to methods of their use; and
`to methods of their storage and deployment.
`2. Description of Related Art
`The prior art discloses a wide variety of depth control
`devices for seismic streamers, some of which are referred to
`as "birds." Typically, a bird is suspended from a streamer
`from a slip ring attached to the streamer and is releasably
`connected thereby to the streamer as it is deployed and
`removed from the streamer as it is recovered. To control
`streamer depth, certain prior art systems use one bird for
`every thousand feet of streamer or for every three "sections."
`Currents, wind, and wave action deflect the streamer
`cables from their intended paths, and streamer cable drift is 20
`a continuing problem for marine seismic surveys. See, for
`example, U.S. Pat. No. 5,532,975. By controlling the posi(cid:173)
`tion and shape of the streamer cables entanglement of the
`streamer cables is avoided and collisions with offshore
`hazards such as marine drilling rigs and production plat(cid:173)
`forms are prevented. Since known 3-D seismic binning
`processes acquire subsurface seismic coverage by combin(cid:173)
`ing seismic data from seismic streamers at different
`locations, it is desirable to have the ability to control the
`position and shape of the streamer cables during marine 3-D
`seismic surveys. The need for this ability is taught by
`Franklyn K. Levin in "Short Note: The effect of binning on
`data from a feathered streamer,"Geophysics, Vol. 49. No.8,
`pp. 1386-1387.
`A variety of streamer positioning devices are well known
`in the art. Apparatus, such as those disclosed in U.S. Pat.
`SUMMARY OF THE PRESENT INVENTION
`Nos. 5,532,975, 4,729,333, and 4,463,701 are attached to
`The present invention, in certain aspects, discloses a
`streamer cables to maintain them at a lateral offset to the
`marine seismic streamer having one or more position control
`pathway of a towing vessel. U.S. Pat. No. 4,890,568 40
`devices or "birds" therein or thereon which do not hang from
`describes steerable tail buoys for controlling the position of
`the streamer but are secured therearound or thereto, or are
`the tail end of towed seismic streamer cables. Streamer
`applied on streamer section connectors. In one aspect, such
`positioning devices that are attached externally to the
`a streamer has one or more position control modules which
`streamer cables to control lateral positioning by using
`are co-axially attached to an exterior of a streamer section
`camber-adjustable hydrofoils or angled wings are disclosed 45 coupling module. Such position control modules, in certain
`in U.S. Pat. Nos. 4,033,278 and 5,443,027. U.S. Pat. No.
`embodiments, have a streamlined and relatively small pro(cid:173)
`3,931,608 discloses a bird for controlling the vertical posi(cid:173)
`file projecting outwardly from the streamer's exterior sur(cid:173)
`tioning of streamer cables with diving planes and a preset
`face thereby making it possible to retrieve the streamer with
`depth control apparatus.
`the depth control modules in place thereon. The modules are
`The prior art discloses a variety of location sensing
`50 retrieved onto a reel with the streamer, i.e., there is no
`devices and methods for determining the positions of seis(cid:173)
`necessity to remove them during streamer retrieval. Also,
`mic sources and seismic streamer cables. A Global Position(cid:173)
`there is, therefore, no necessity to attach them to the
`ing System, described in U.S. Pat. No. 4,809,005 and a
`streamer as it is being deployed. The streamlined profile also
`network of acoustic elements described in U.S. Pat. No.
`inhibits tangling of the streamer with another streamer, with
`4,912,682 may be deployed on a vessel, streamer cables, and
`55 fishing lines and nets, etc.
`tail buoy and may then be used to determine the real-time
`In one aspect the position control modules or "birds" have
`position of seismic sources and seismic streamer cables by
`a body and one, two, three, four or more control surfaces
`computing a network solution with a Kalman filter, e.g. as
`initially disposed in recesses in the body. The control
`disclosed by U.S. Pat. No. 5,353,223.
`surfaces are selectively movable from the body to contact
`In known prior art methods of marine seismic surveying,
`60 the water in which the streamer is deployed to effect a
`a human operator monitors the survey's operational
`change in depth and/or lateral position of the streamer and
`conditions, such as the extent of subsurface seismic
`to maintain the streamer at a desired location relative to a
`coverage, the adequacy of separations between streamer
`tow vessel. In one aspect the bird is fixedly attached around
`cables, and the proximity of streamer cables to obstructive
`the streamer, and rotates or twists as the streamer rotates or
`65 twists. In another aspect, the bird is loosely positioned
`hazards. When these conditions indicate the need to repo(cid:173)
`around streamer and aligns itself to the gravity normal by
`sition the streamer cables, the operator may manually issue
`commands to various individual streamer positioning
`gravity and/or by mechanical means.
`
`Ex. PGS 1005
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`6,011,752
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`5
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`15
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`4
`Such a streamer with position control modules spaced(cid:173)
`apart a relatively short distance for greater control of
`streamer depth; and
`New, useful, unique, efficient and nonobvious methods
`for using such streamers.
`Certain embodiments of this invention are not limited to
`any particular individual feature disclosed here, but include
`combinations of them distinguished from the prior art in
`their structures and functions. Features of the invention have
`10 been broadly described so that the detailed descriptions that
`follow may be better understood, and in order that the
`contributions of this invention to the arts may be better
`appreciated. There are, of course, additional aspects of the
`invention described below and which may be included in the
`subject matter of the claims to this invention. Those skilled
`in the art who have the benefit of this invention, its
`teachings, and suggestions will appreciate that the concep(cid:173)
`tions of this disclosure may be used as a creative basis for
`designing other structures, methods and systems for carrying
`out and practicing the present invention. The claims of this
`invention are to be read to include any legally equivalent
`devices or methods which do not depart from the spirit and
`scope of the present invention.
`The present invention recognizes and addresses the
`25 previously-mentioned problems and long-felt needs and
`provides a solution to those problems and a satisfactory
`meeting of those needs in its various possible embodiments
`and equivalents thereof. To one skilled in this art who has the
`benefits of this invention's realizations, teachings,
`30 disclosures, and suggestions, other purposes and advantages
`will be appreciated from the following description of pre(cid:173)
`ferred embodiments, given for the purpose of disclosure,
`when taken in conjunction with the accompanying drawings.
`The detail in these descriptions is not intended to thwart this
`35 patent's object to claim this invention no matter how others
`may later disguise it by variations in form or additions of
`further improvements.
`
`20
`
`3
`In one aspect each depth control module has one or more
`internal accelerometers to sense and indicate direction of a
`gravity vector. Commands generated by a tow vessel may
`instruct the bird to change streamer depth and/or lateral
`position. This is accomplished, in certain preferred
`embodiments, by fuzzy or proportional control algorithms
`within a bird microprocessor. The purpose of the micropro(cid:173)
`cessor is to adjust bird "wing" angles to achieve a desired
`change in position given the configuration of the "swings"
`on the bird and the relative orientation of the bird with
`respect to the gravity vector. Commands are communicated
`between the streamer control system on-board the tow vessel
`and the bird along wires or fiber-optic channels within the
`streamer. Status of the bird health and activity may also be
`communicated on such channels back to the tow-vessel.
`Certain particular bird control methods and systems are
`disclosed in pending U.S. application Ser. No. 08/771,049
`filed on Dec. 20, 1996, co-owned with the present invention,
`and incorporated fully herein for all purposes.
`In one aspect the control surfaces are releasable from an
`extended position in response to contact with an obstruction.
`In one embodiment, control surfaces of a bird are flexibly
`attached to a streamer by a spring or springs of sufficient
`stiffness to prevent the axis of the "wing" from bending
`under normal hydrodynamic loading. In the event that the
`"owing" comes into contact with foreign objects (e.g. but
`not limited to another streamer, fish pot buoy lines, fishing
`lines, etc.) the spring(s) allow the "wing" to be deflected and
`thereby prevent or minimize damage to the bird and reduce
`the risk of entanglement with foreign objects.
`In one embodiment the control modules are incorporated
`into a streamer section rather than secured around it. In one
`aspect the control modules are disposed in streamer con(cid:173)
`nection modules that connect two streamer sections. Posi(cid:173)
`tion control devices disposed in these ways may include
`power and/or signal transmission apparatus for conveying
`power and/or signals between streamer sections.
`In one embodiment, the wings of a bird are opened and
`closed in a plane parallel to the diameter of a control module.
`Wings may be housed on or in a streamer-position-module.
`In another embodiment, the wings of a bird are opened
`and closed in a plane perpendicular to the diameter of the
`control module. In one such embodiment, two short wings
`are deployed at right angles to a larger wing which produces
`comparable lift for the same angle-of-attack of the two
`smaller wings.
`What follows are some of, but not all, the objects of this
`invention. In addition to the specific objects stated below for
`at least certain preferred embodiments of the invention,
`other objects and purposes will be readily apparent to one of
`skill in this art who has the benefit of this invention's
`teachings and disclosures. It is, therefore, an object of at
`least certain preferred embodiments of the present invention
`to provide:
`New, useful, unique, efficient, nonobvious se1sm1c
`streamers and such streamers with one or more position 55
`control devices thereon or therein;
`Such a seismic streamer with position control device(s)
`with a streamlined profile so that the streamer with the
`device(s) thereon and/or therein may be easily retrieved on
`a reel and deployed from a reel;
`Such a position control device with at least one or a
`plurality of selectively movable angle-of-attack control sur(cid:173)
`face which is/are positioned within a recess in a body of the
`module and movable outwardly therefrom;
`Such a streamer with such position control modules which 65
`is less likely to entangle with another streamer or other
`object;
`
`50
`
`40
`
`45
`
`DESCRIPTION OF THE DRAWINGS
`A more particular description of embodiments of the
`invention briefly summarized above may be had by refer(cid:173)
`ences to the embodiments which are shown in the drawings
`which form a part of this specification. These drawings
`illustrate certain preferred embodiments and are not to be
`used to improperly limit the scope of the invention which
`may have other equally effective or legally equivalent
`embodiments.
`FIG. 1 is a perspective view of a seismic streamer and
`control module according to the present invention.
`FIG. 2 is a perspective view of the seismic streamer of
`FIG. 1 with control surfaces of the control module extended.
`FIG. 3A is a perspective view of a seismic streamer and
`depth control module according to the present invention.
`FIG. 3B shows the streamer of FIG. 3A with wings
`extended.
`FIG. 4A is a perspective view of a seismic streamer and
`depth control module according to the present invention.
`FIG. 4B shows the streamer of FIG. 4A with wings
`extended. FIG. 4C, FIG. 4D, and FIG. 4E are side cross-
`60 section views of a wing apparatus of the streamer of FIG.
`4A. FIG. 4F is a cross-section view along line 4F-4F of
`FIG. 4A.
`FIG. 5 is a perspective view of a flange used with the
`streamer of FIG. 4A.
`FIG. 6Apresents schematically a position for the streamer
`of FIG. 4A. FIG. 6B presents schematically a position for
`the streamer of FIG. 4A.
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`Ex. PGS 1005
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`6,011,752
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`5
`FIG. 7 presents schematically a signal flow diagram for a
`seismic streamer system according to the present invention.
`
`DESCRIPTION OF EMBODIMENTS
`PREFERRED AT 1HE TIME OF FILING FOR
`THIS PATENT
`
`5
`
`6
`position by interior side walls of slots 71. A sensor 65
`interconnected with the control apparatus 60 and each wing
`senses the wing angle and transmits a signal indicative
`thereof to the control apparatus 60. The control apparatus 60
`is in communication with a streamer-position-module con(cid:173)
`troller which, in one aspect, is located within the bird 50 and
`in communication with a remote control apparatus; and, in
`another aspect, is located on the tow vessel and is in
`communication with the apparatus 60.
`FIG. 7 illustrates a signal flow diagram for the streamer(cid:173)
`position-control-module. This module computes an angle(cid:173)
`of-attack for each wing. In one aspect a rotationally balanced
`force is produced on the streamer to achieve desired vertical
`or horizontal streamer movement. The dotted line in FIG. 7
`indicates a subset of streamer components. A computer
`assisted navigator apparatus (or a human operator) generates
`"STREAMER CONTROL SIGNALS" (e.g. depth setting,
`movement right or left). These signals are sent via the
`streamer to the bird's control apparatus ("FUZZY LOGIC
`20 CONTROL"). The "STREAMER POWER" apparatus pro(cid:173)
`vides electric power for on-streamer electronics and for
`wing rotation. A ROLL SENSOR senses streamer roll and
`sends signals indicative thereof to the control apparatus. A
`DEP1H SENSOR senses streamer depth and sends signals
`25 indicative thereof to the control apparatus. A WING ANGLE
`OF ATTACK SENSOR senses wing attitude and sends
`signals indicative thereof to the control apparatus.
`A conceptual model of a bird with an even number of
`control surfaces uniformly disposed about the bird and
`30 attached to a streamer is shown in FIGS. 6A and 6B. The
`dotted line arrow in FIG. 6A indicates a gravity vector. To
`effect a vertical change in position, a net vertical force is
`produced by independently adjusting the angle of attack of
`each wing using the following mathematical relationship:
`
`Referring now to FIG. 1, a seismic streamerS according
`to the present invention has a streamer body 12 of any
`desired length. A depth control module or "bird" 10 with a
`body 22 is secured on the body 12 of the seismic streamer 10
`S. Ends 24 of the body 22 are, preferably, faired or tapered
`to form a streamlined profile for a control module 20. One
`or both ends may be faired or tapered for smooth hydrody(cid:173)
`namic flow.
`A plurality of control surfaces or wings 26 are initially 15
`disposed in recesses 28, as shown in FIG. 1, so that they are
`flush with the exterior surface of the body 22.
`The wings 26 are movable out from the recesses 28 by
`control and power apparatus 14 (shown schematically in
`FIG. 1) within the body 22. Once extended, the wings 26 are
`also rotatable to adjust their attitude with respect to the body
`22. The control apparatus may be physically linked to a tow
`vessel's on-board controls or it may be controlled remotely
`from the tow vessel.
`FIGS. 3A and 3B show a bird 30 according to the present
`invention on a streamer S with a body 32; faired ends 34;
`wing recesses 36 for wings 38; and wing recess 42 for wing
`44. The wings 38 and 44 are movable as are the wings 26
`(FIG. 1) and have similar control and power apparatus.
`FIG. 4A shows a seismic streamer bird SO according to
`the present invention with a body 52 having tapered ends 54
`and four wing recesses 58 in which are disposed movable
`wings 56. Each wing is independently movable by control
`apparatus 60 (shown schematically) enclosed in a water- 35
`proof enclosure 61 (see FIG. 4F). FIG. 4B shows the wings
`56 extended and rotated. The body is emplaceable on a
`seismic streamer extending through a central channel 51.
`FIGS. 4C-4E illustrate a wing mount 62 as used with each
`wing 56. The wing mounts 62 include a flexible/breakaway 40
`joint 64 (e.g. but not limited to a spring member whose
`tensile strength is known and which will break in response
`to a known force on the wing). The joint 64 is part of a shaft
`66 that has one end secured to the wing 56 and the other end
`secured to a gear 67. At an intermediate point the shaft 66 45
`rotatably extends through a waterproof ball and socket joint
`63 that is itself rotatably secured by pins 59 to the body 52
`of the streamer 50.
`FIG. 4E shows the position of the shaft 66 when a wing
`is housed in its recess 58. FIG. 4C shows the position of the
`shaft 66 when a wing is extended as in FIG. 4B. As shown
`in FIG. 4C a gear 67 on a lower end of the shaft 66 is turned
`by a corresponding worm gear 69 which is interconnected
`with the control apparatus 60. Turning of the worm gear 69
`adjusts the attitude of the wing 56 connected to the shaft 66.
`Each shaft 66 has its own corresponding worm gear and is
`interconnected with the control apparatus. A flange 68 is
`rotatably fixed inside the bird body 52. Slots 71 (one for each
`of four wing shafts 66) are cut through the flange 68. An
`interior portion of the shafts 66 between the gear 67 and the 60
`socket joint 63 passes through the flange 68 in the slot 71.
`When the flange 68 is rotated by the control apparatus 60
`about an axis coincident with an axis of the streamer
`module, the shaft 66 rotates about an axis defined by the pins
`59. Thus, the wings 56 may rotate through a 90° arc (as in 65
`FIGS. 4C, 4E) to deploy and retract. When the flange 68 is
`rotated to its maximum extent, the shaft 66 is locked into
`
`Where n is the control surface identification and av repre(cid:173)
`sents the nominal angle-of-attack for a hypothetical control
`surface with area AH oriented in the horizontal plane having
`a wing area equal to Y2 of the sum of actual control surfaces.
`
`n
`A= ~An
`1
`
`(where A, is the area of each wing)
`The resulting hydrodynamic force is balanced about a
`vertical line passing through the centerline of the bird. The
`50 thrust produced by wings on each side of the vertical
`produce force vectors parallel to the vertical plane and equal
`in magnitude.
`Similarly, to produce a lateral change in position, a net
`horizontal force is produced by independently adjusting the
`55 angle-of-attack of each wing using the following relation(cid:173)
`ship:
`
`To effect a change in the vertical and horizontal position,
`the sum of computed angles will produce a net force
`balanced about a plane inclined to the vertical and thus will
`not produce a rotational force on the streamer.
`
`In certain embodiments, a change in vertical position is
`easily automated with a depth sensor providing input to the
`
`Ex. PGS 1005
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`6,011,752
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`7
`on-board microprocessor. The desired streamer depth may
`be dynamically set by a human or by a computer controller
`on the tow vessel. A depth command is communicated to the
`bird controller by electrical or optical signals carried on
`conductors built into the streamer. The vertical position may
`be defined to achieve a particular depth suitable for seismic
`data acquisition or may be set to protect the streamer from
`collision with surface or subsurface obstructions. The bird
`controller sets wing angle to move the streamer toward the
`desired depth. As the streamer approaches the programmed
`depth, wing angles are decreased so that the streamer does
`not overshoot the programmed depth and thus risk
`undamped oscillation about the programmed depth. A
`change in lateral position requires input from a position
`measurement system (in one aspect on board a tow vessel)
`which may receive input from GPS, acoustic, or inertial
`navigation components.
`For a bird with an odd number of wings, the mathematical
`formulas and computations are similar to those discussed
`above for a bird with an even number of wings.
`The present invention, therefore, in certain embodiments,
`provides a bird for a seismic streamer for controlling posi(cid:173)
`tion of the seismic streamer, the bird having a body with a
`first end and a second end and a bore therethrough from the
`first end to the second end for receiving a seismic streamer 25
`therethrough, one or a plurality of wings, each wing mov(cid:173)
`ably connected to a shaft connected to the body, a recess in
`the body for each wing, the wing or wings movably con(cid:173)
`nected to the shafts for movement from and into the
`recesses, and the shafts rotatable with respect to the body,
`and control apparatus interconnected with the shafts for
`controlling wing movement to and from the recesses and for
`controlling wing attitude!; such a bird wherein the first end
`of the body and the second end of the body are tapered ends;
`any such bird with control apparatus within the body inter(cid:173)
`connected with the at least one wing for controlling move(cid:173)
`ment of the at least one wing; any such bird with power
`apparatus for moving the at least one wing, the power
`apparatus controlled by the control apparatus; any such bird
`with flexible mount apparatus for mounting each wing to the
`body; any such bird with breakaway mount apparatus for
`mounting each wing to the body; any such bird wherein the
`at least one wing is a plurality of wings; any such bird
`wherein the plurality of wings includes at least one first wing
`movable to a first position and at least one second wing
`movable to a second position; any such bird wherein the first
`and second wings are parallel with respect to, at an angle to,
`or are perpendicular to each other following movement from
`their respective recesses; any such bird wherein each wing
`of the plurality of wings is interconnected with a sensor that
`senses attitude of the wing and transmits a signal to control
`apparatus in the body indicative of wing attitude, the control
`apparatus including a mechanism for adjusting the attitude
`of each wing.
`The present invention, therefore, in certain embodiments,
`provides a bird for a seismic streamer for controlling posi(cid:173)
`tion of the seismic streamer, the bird having a body with a
`first end and a second end and a bore therethrough from the
`first end to the second end for receiving a seismic streamer
`therethrough, a plurality of wings movably connected to the
`body with flexible mount apparatus, a plurality of recesses
`in which is initially disposed one of the wings, each wing
`movably connected to the body for movement from and into
`a recess and for attitude adjusting movement with respect to
`the body when the wing is outside the recess, control
`apparatus within the body interconnected with each wing for
`controlling movement of each wing, power apparatus for
`
`8
`moving each wing, the power apparatus controlled by the
`control apparatus, and each wing of the plurality of wings
`interconnected with a sensor that senses attitude of the wing
`and transmits a signal to the control apparatus indicative of
`5 wing attitude, the control apparatus including a mechanism
`for adjusting the attitude of each wing.
`The present invention, therefore, provides in certain
`embodiments, a seismic streamer system with one or a
`plurality of seismic streamers each having a streamer body,
`10 at least one bird mounted to the streamer body, the bird
`having a body with a first end and a second end and a bore
`therethrough from the first end to the second end for
`receiving the seismic streamer therethrough, at least one
`wing movably connected to the body, at least one recess in
`15 which is initially disposed the at least one wing, the at least
`one wing movably connected to the body for movement
`from and into the at least one recess and for attitude
`adjusting movement with respect to the body when the at
`least one wing is outside its recess; such a seismic streamer
`20 system wherein the at least one wing is a plurality of wings
`and the at least one bird has control apparatus within the
`body interconnected with each wing for controlling move(cid:173)
`ment of each wing, power apparatus for moving each wing,
`the power apparatus controlled by the control apparatus, and
`flexible mount apparatus for mounting each wing to the
`body; any such seismic streamer system wherein the at least
`one bird is a plurality of spaced-apart birds; and any such
`seismic streamer system wherein the at least one bird has a
`plurality of wings including at least one first wing movable
`30 to a first position and at least one second wing movable to
`a second position.
`The present invention, therefore, provides in at least
`certain embodiments, a method for controlling a seismic
`streamer, the method including moving the seismic streamer
`35 through water, the seismic streamer having secured thereto
`at least one bird, the at least one bird having a body with a
`first end and a second end and a bore therethrough from the
`first end to the second end for receiving a seismic streamer
`therethrough, at least one wing movably connected to the
`40 body, at least one recess in which is initially disposed the at
`least one wing, the at least one wing movably connected to
`the body for movement from and into the at least one recess
`and for attitude adjusting movement with respect to the body
`when the at least one wing is outside its recess, and
`45 activating the at least one wing of the at least one bird to
`control position of the seismic streamer; such a method
`wherein the at least one bird has control apparatus within the
`body interconnected with the at least one wing for control(cid:173)
`ling movement of the at least one wing, power apparatus
`50 within the body, adjacent thereto, or remote therefrom and
`interconnected therewith for power transmission thereto, for
`moving the at least one wing, the power apparatus controlled
`by the control apparatus, the at least one wing is a plurality
`of wings including at least one first wing movable to a first
`55 position and at least one second wing movable to a second
`position; and such a method wherein the first and second
`wings are at an angle to, parallel to, or perpendicular to each
`other following movement from their respective recesses.
`In conclusion, therefore, it is seen that the present inven-
`60 tion and the embodiments disclosed herein and those cov(cid:173)
`ered by the appended claims are well adapted to carry out the
`objectives and obtain the ends set forth. Certain changes can
`be made in the subject matter without departing from the
`spirit and the scope of this invention. It is realized that
`65 changes are possible within the scope of this invention and
`it is further intended that each element or step recited in any
`of the following claims is to be understood as referring to all
`
`Ex. PGS 1005
`
`
`
`6,011,752
`
`15
`
`20
`
`30
`
`9
`equivalent elements or steps. The following claims are
`intended to cover the invention as broadly as legally possible
`in whatever