Abstract: It is described a node handling device for use during deployment or retrieval of a plurality of seismic nodes (10) attacked to a cable (8), the node handling device comprising: a wheel device (1) adapted for damping of the cable (8) with attached seismic nodes (10) during deployment or retrieval. A wheel device and a method for deployment or retrieval are also disclosed.

Abstract: Method for time drift measurement of at least one slave clock in at least one seismic node, wherein the time drift measurement is performed in the at least one seismic node. The seismic node is configured for receiving a master clock signal and obtaining a time drift between the slave clock and the master clock signal.

Abstract: It is described an attachment device (2) for attaching a seismic node to a cable (1), the attachment device comprising an in-line fastening device (6) fastening the cable (1); and at least one locking device (3) securing the cable (1) in the at least one in-line fastening device (6). The locking device (3) prevents the cable (1) from escaping the fastening device (6). A seismic node and a method for deployment and retrieval of a number of seismic nodes are also described.

Abstract: It is described a node handling device for use during deployment or retrieval of a plurality of seismic nodes (10) attacked to a cable (8), the node handling device comprising: a wheel device (1) adapted for damping of the cable (8) with attached seismic nodes (10) during deployment or retrieval. A wheel device and a method for deployment or retrieval are also disclosed.

Abstract: It is described an attachment device (2) for attaching a seismic node to a cable (1), the attachment device comprising an in-line fastening device (6) fastening the cable (1); and at least one locking device (3) securing the cable (1) in the at least one in-line fastening device (6). The locking device (3) prevents the cable (1) from escaping the fastening device (6). A seismic node and a method for deployment and retrieval of a number of seismic nodes are also described.

Abstract: A steerable seismic energy source includes at least one float. The floatation device includes a device for changing buoyancy thereof. A frame is coupled to the at least one float. At least one seismic energy source is suspended from the frame. At least one steering device is coupled to the floatation device or the frame. The at least one steering device includes at least one control surface and a control surface actuator coupled to the control surface. The actuator is configured to rotate the control surface to generate hydrodynamic lift at least in a vertical direction.

Abstract: A steerable seismic energy source includes at least one float. The floatation device includes a device for changing buoyancy thereof. A frame is coupled to the at least one float. At least one seismic energy source is suspended from the frame. At least one steering device is coupled to the floatation device or the frame. The at least one steering device includes at least one control surface and a control surface actuator coupled to the control surface. The actuator is configured to rotate the control surface to generate hydrodynamic lift at least in a vertical direction.

Abstract: A steerable seismic energy source includes at least one float. The floatation device includes a device for changing buoyancy thereof. A frame is coupled to the at least one float. At least one seismic energy source is suspended from the frame. At least one steering device is coupled to the floatation device or the frame. The at least one steering device includes at least one control surface and a control surface actuator coupled to the control surface. The actuator is configured to rotate the control surface to generate hydrodynamic lift at least in a vertical direction.

Abstract: A motion compensation system for a helipad on a vessel includes a sensor for measuring a parameter related to at least one or pitch and roll of the vessel. The system includes a first actuator functionally coupled to the helipad to move the helipad translationally with respect to the vessel in response to the measured at least one of pitch and roll of the vessel.

Abstract: A steerable seismic energy source includes at least one float. The floatation device includes a device for changing buoyancy thereof. A frame is coupled to the at least one float. At least one seismic energy source is suspended from the frame. At least one steering device is coupled to the floatation device or the frame. The at least one steering device includes at least one control surface and a control surface actuator coupled to the control surface. The actuator is configured to rotate the control surface to generate hydrodynamic lift at least in a vertical direction.

Abstract: A motion compensation system for a helipad on a vessel includes a sensor for measuring a parameter related to at least one or pitch and roll of the vessel. The system includes a first actuator functionally coupled to the helipad to move the helipad translationally with respect to the vessel in response to the measured at least one of pitch and roll of the vessel.

Abstract: A helipad motion compensation system for a vessel includes at least one controllable length actuator operatively coupled between the helipad and the vessel. The system also includes an attitude sensor disposed on at least one of the helipad and the vessel. The sensor produces signals corresponding to change in attitude of the helipad. A controller is in operative communication with the sensor and is arranged to operate the at least one actuator. The actuator is operable to substantially maintain an attitude of the helipad to compensate for motion of the vessel.