Abstract:
Method and apparatus for mitigating vibrations in a device towed in water. The apparatus includes one or more tuned elastic sections having a complex spring rate and adapted to attenuate vibrations in a specified frequency range; and a head end coupler adapted to couple the apparatus for vibration mitigation to a component of an electro-mechanical cable or a tow assembly. One of the one or more tuned elastic sections is coupled to the head end coupler with a high impedance material interface.
Abstract:
A method and apparatus are provided for steering a first acoustic linear antenna belonging to a plurality of acoustic linear antennas towed by a vessel. A plurality of navigation control devices are arranged along the plurality of linear antennas in order to act at least laterally on the position of the linear antennas. At least one of the navigation control devices arranged along the first acoustic linear antenna performs steps of: obtaining a local measurement of a feather angle or of a parameter linked to the feather angle, the local measurement being associated with the at least one of the navigation control devices arranged along the first acoustic linear antenna; computing a lateral force, as a function of the obtained local measurement; and applying the computed lateral force.
Abstract:
Method and dynamic vibration absorber device for reducing a resonant frequency of a node to which the dynamic vibration absorber device is attached to. The dynamic vibration absorber device includes a housing configured to be attached to the node; an absorber mass located inside the housing; and first and second diaphragms attached to the housing and configured to suspend the absorber mass inside the housing. The dynamic vibration absorber device changes a resonant frequency of the node to two smaller vibration peaks.
Abstract:
A seismic detection line includes one or more identified element(s) arranged in a string, and a telemetry link connecting the element(s) along the string to convey seismic data from at least one of the element(s) to a data recorder and identification data to a topology controller. Each of the element(s) includes a respective first identification unit connected to the telemetry link to provide a respective first identifier to the topology controller. A seismic detection system also includes a processor that queries the identified element(s) for their respective identifiers, determines an arrangement of the seismic detection line using the received identifiers, and presents an indication of the determined arrangement. A method of operating a seismic detection line includes transmitting a query along the telemetry link, detecting whether the respective identifier of one of the element(s) was received or not, repeating until termination, and determining and indicating the arrangement.