method and device for precise positioning of a schwimmkoerpers in relation to a sub aquatic village

摘要

1,122,243. Determining position acoustically. TEXACO DEVELOPMENT CORP. 15 April, 1966 [29 April, 1965], No. 16567/66. Heading H4D. [Also in Divisions E1 and G4] Apparatus for guiding equipment 42 during lowering from a water surface so as to enter an under water well bore 16 comprises ultrasonic frequency transmitters 27, 28 mounted on a base member 21 which surrounds the well bore 16 and an equipment carrying bracket 46 provided with receiving pods 47, 48, each having three sonic receiving transducers 51, 52, 53, Fig. 2, associated with propulsion units 56, 57, 58 respectively. Each propulsion unit is provided with a servomotor 61 and propeller 62. The speed of each servomotor 61 is proportional to the electrical input signal from its associated receiving transducer 51, 52 or 53 so that the pods 47, 48 locate and stay centred on the beams generated from the transmitters 27, 28 respectively. As shown, transmitters 27, 28 are electrically energized from a drilling vessel 11 via a buoy 31 through cables 41, 36. Cable 36 comprises a lead 34 which energizes transmitter 28 and two leads 29, 32 which energize transmitter 27. Transmitter 27 is energized through one of its leads by means of a switch (62), Fig. 5 (not shown), so that a relatively low frequency ultrasonic beam is generated. The drilling vessel is manoeuvered until a maximum in received intensity indicates that the near centre of the ultrasonic beam is detected by receiving pod 47. Transmitters 27, 28 are then switched to their high frequency ultrasonic transmitting mode and equipment bracket 46 is rotated about the axis of the beam from transmitter 27 until receiving pod 48 senses and locks on to the generated beam from transmitter 28. The drilling ship is then anchored and equipment 42 carried by bracket 46 is lowered and automatically guided along the beams towards the well bore.