Deployment of seismic sensor
An arrangement for the deployment of seismic sensor units, such as sensor nodes ( 24 ), on the seabed includes a frame structure that is adapted to carry a container ( 11 ) for containment of a data registration unit and additional auxiliary equipment for the sensor node. The arrangement has supports ( 12, 13 ) that can rest against the seabed, and an attachment means ( 17 ) for a lifting hook, for raising and lowering by means of a crane. There is a holder ( 20 ) for the sensor node ( 24 ) that can be positioned on the seabed and which is connected to the container through a signal cable ( 32 ). A releasable attachment means ( 22 ) holds the sensor node ( 24 ) in a downwardly extending position with respect to the supports ( 12, 13 ). The attachment means ( 22 ) is located with a horizontal distance from the container ( 11 ). A latch mechanism ( 25 ) for the attachment means ( 22 ) is adapted to release the sensor node ( 24 ).
1. An apparatus comprising:
a sensor node ( 24 ) having a main body;
a container ( 11 ; 33 ) that contains a data registration unit that is remotely controlled for registration of seismic data collected by the sensor node ( 24 );
a frame structure ( 12 , 13 ; 34 ) that carries the container and that rests on the seabed;
a lifting device ( 17 ; 51 ) that lifts and lowers the frame structure;
a signal cable ( 32 ) that connects the sensor node to the container;
a releasable fastener ( 22 ; 47 , 48 ) that supports the sensor node ( 24 ) to the frame structure and releases the sensor node ( 24 ) after at least a portion of the main body of the sensor node is inserted into the seabed at a horizontal distance from the container ( 11 ; 33 );
a pair of carrier arms ( 20 , 27 ) extending from opposite sides of the container ( 11 ) wherein each carrier arm has a support plate ( 29 , 28 ) that contacts the seabed only when the sensor node ( 24 ) is inserted into the seabed;
wherein the sensor node ( 24 ) is positioned juxtaposed to one support plate ( 29 ); and,
wherein the other support plate ( 28 ) has an area-moment about a main axis that is approximately the sum of the area-moments of the support plate ( 29 ) and the sensor node ( 24 ).
2. The apparatus according to claim 1 wherein the releasable fastener comprises a latch pin ( 25 ) that is moveable with respect to the carrier arms and received in a carrier bracket ( 23 ) mounted to the sensor node ( 24 ).
3. The apparatus according to claim 1 wherein the releasable fastener comprises a pair of claws ( 47 , 48 ).
4. The apparatus according to claim 1 wherein the releasable fastener ( 22 ; 47 , 48 ) positions the sensor node ( 24 ) into the seabed at a fixed horizontal distance from the container ( 11 ; 33 ).
5. An apparatus comprising:
a sensor node ( 24 ) having a main body;
a container ( 11 ; 33 ) that contains a data registration unit that is remotely controlled for registration of seismic data collected by the sensor node ( 24 );
a frame structure ( 12 , 13 ; 34 ) that carries the container and that rests on the seabed;
a lifting device ( 17 ; 51 ) that lifts and lowers the frame structure;
a signal cable ( 32 ) that connects the sensor node to the container; and,
a releasable fastener ( 22 ; 47 , 48 ) that:
a) supports the sensor node ( 24 ) to the frame structure at a fixed location with respect to the frame structure as the frame structure is lowered toward the seabed;
b) maintains the sensor node ( 24 ) at the fixed location as at least a portion of the main body of the sensor node is inserted into the seabed at a horizontal distance from the container ( 11 ; 33 ); and,
c) releases the sensor node ( 24 ) after the at least a portion of the main body of the sensor node is inserted into the seabed.
6. The apparatus according to claim 5 wherein the releasable fastener ( 22 ) is arranged on a carrier arm ( 20 ), which extends laterally out from the container ( 11 ).
7. The apparatus according to claim 5 wherein the releasable fastener comprises a latch pin ( 25 ) that is moveable with respect to the carrier arm and received in a carrier bracket ( 23 ) mounted to the sensor node ( 24 ).
8. The apparatus according to claim 5 wherein the releasable fastener comprises a pair of claws ( 47 , 48 ).
9. The apparatus according to claim 5 wherein the releasable fastener ( 22 ; 47 , 48 ) positions the sensor node ( 24 ) into the seabed at a fixed horizontal distance from the container ( 11 ; 33 ).