A method of upgrading a knuckle-boom crane to a heave-compensating crane includes: removing a knuckle-boom from a main boom; mounting a main boom extension to the main boom for increasing the length of the main boom; and mounting a heave-compensating boom at a far end of the main boom extension such that the heave-compensating boom extends in a downward vertical direction (Z) in operational use of the heave-compensating crane. The heave-compensating boom is configured to be pivotable with respect to the main boom extension in both horizontal directions (X, Y). A heave-compensation system is provided to the knuckle-boom crane, wherein the heave-compensation system compensates for horizontal variations by controlling the orientation of the heave-compensating boom relative to the main boom extension, and compensates for vertical variations by means of a further vertical heave-compensation system, such as a winch-based heave-compensation system.

Described herein are systems, methods, and structures for transferring an object between a ship and an offshore structure, comprising a hoisting mechanism arranged on the offshore structure and adapted to attach to the object, at least one range sensing device adapted to provide data relating to a detected distance from a reference point on the offshore structure to the ship, where the system is adapted to receive the data from the at least one range sensing device and to move the hoisting cable in response to the detected distance, and a motion reference unit adapted to provide data relating to a detected motion of the ship independently of the at least one range sensing device, and wherein the system is adapted to move the hoisting cable in response to the detected motion of the ship.

An unmanned aerial device according to an aspect of the present invention includes an aerial device body capable of flying in an unmanned manner, and a load-lowering device mounted to the aerial device body and configured to lower a load from the aerial device body. The load-lowering device has a linear member holder for holding a linear member having one end portion connectable to the load, the linear member holder holding at least the other end portion of the linear member, and a speed limiting mechanism that limits a speed at which the linear member is pulled out of the linear member holder, under a weight of the load.

The support mechanisms of the present invention comprise a vessel supported by suspension cables suspended from trollies that can move along the length (longitudinal) of a framework. The support system is such that waste material, even upon heating, cooling, etc., can constantly and smoothly move through the entire system, with the vessel generally being in a natural, balanced orientation.

There is described a hoisting system and method of lifting that make use of a particular fibre rope. The fibre rope includes a plurality of magnets that are embedded within the fibre rope and spaced apart along the rope with a known axial distance between the magnets. The system may include a fibre rope hoisting speed sensor, and a magnetic field sensor that can sense the presence of the magnetic field of the embedded magnets. Using the sensors, the hoisting speed of the rope may be determined by: measuring the time between the passing of consecutive magnets by using the magnetic field sensor; calculating the distance between consecutive magnets using the hoisting speed sensor and the measured time between the passing of the consecutive magnets; and comparing the calculated distance between the magnets with an original, predefined distance between the magnets.

A hoisting system is for hoisting a vertically-suspended object. The hoisting system has a winch having a winch drum with a hoisting rope. A first part of the hoisting rope has a first diameter and a second part has a second diameter being larger than the first diameter. The first part is connected with a first end of the second part. The first part is an inner part on the winch drum when the winch drum is completely wound. The second part has a further end that is connectable to the object for hoisting the object. A ratio between the first diameter and the second diameter is such that the minimum breakable load of the first part differs less than a factor of four from the minimum breakable load of the second part, and preferably less than a factor of three. A corresponding method is disclosed.

An unmanned robot system for a tethered robot, for example, a tethered aircraft, is disclosed. The unmanned system, in one embodiment, includes an unmanned aircraft tethered to a ground station by a tether cable. In one embodiment, an aerial winch and cable unit is provided on the aircraft to manage cable release. Alternatively, winch and cable units may be provided on both the aircraft and ground station. As the aircraft is now able to freely operate cable release to overcome any disturbances along the cable length, the operational effectiveness of the aircraft is greatly improved.

A tension balance system for steel wire ropes on a friction hoisting driving end of an ultra-deep well includes a friction wheel, left and right guiding wheels, left and right steel wire ropes, left and right adjustment wheels, left and right rewinding wheels, left and right adjustment oil cylinders, a hydraulic pipeline, a pump station, a pipeline switch group, left and right hoisting containers, balance ropes, and reels. The friction wheel is disposed in the middle, the left and right adjustment wheels and the left and right rewinding wheels are circularly distributed around the friction wheel, the left and right guiding wheels, the left and right adjustment wheels, and left and right rewinding wheels are all symmetrically disposed on two sides of the friction wheel; both a quantity of left steel wire ropes and a quantity of right steel wire ropes are even numbers more than 2.

A tension balance system for steel wire ropes on a friction hoisting driving end of an ultra-deep well includes a friction wheel, left and right guiding wheels, left and right steel wire ropes, left and right adjustment wheels, left and right rewinding wheels, left and right adjustment oil cylinders, a hydraulic pipeline, a pump station, a pipeline switch group, left and right hoisting containers, balance ropes, and reels. The friction wheel is disposed in the middle, the left and right adjustment wheels and the left and right rewinding wheels are circularly distributed around the friction wheel, the left and right guiding wheels, the left and right adjustment wheels, and left and right rewinding wheels are all symmetrically disposed on two sides of the friction wheel; both a quantity of left steel wire ropes and a quantity of right steel wire ropes are even numbers more than 2.

A system for bridle bite adjustment can include a tow rope coupled to a paravane at a first position on a lever arm and a spur line coupled to the paravane at a second position on the lever arm. The system can also include a winch to adjust a deployed length of the tow rope. The tow rope and the lever arm can adjust a bridle bite of the paravane by when the deployed length of the tow rope is adjusted by the winch, thereby balancing tension between the tow rope and the spur line.