A lift system for a rotor blade of a wind turbine includes a lifting device having a structural frame body having a root end and a tip end. The root end supports a root cradle and the tip end supports a tip cradle. The root and tip cradles each have a profile that corresponds to at least one exterior surface of the rotor blade so as to receive and support at least a portion of the rotor blade. Due to a shape of the rotor blade, when the rotor blade is installed in the lifting device and lifted uptower, the rotor blade can experience an asymmetric loading. Accordingly, the lift system also includes a variable airflow assembly coupled to tip end of the lifting device. The variable airflow assembly includes at least one surface moveable between a plurality of positions having varying resistances so as to counteract the asymmetric loading.

A lift system for a rotor blade of a wind turbine includes a lifting device having a structural frame body having a root end and a tip end. The root end supports a root cradle and the tip end supports a tip cradle. The root and tip cradles each have a profile that corresponds to at least one exterior surface of the rotor blade so as to receive and support at least a portion of the rotor blade. Due to a shape of the rotor blade, when the rotor blade is installed in the lifting device and lifted uptower, the rotor blade can experience an asymmetric loading. Accordingly, the lift system also includes a variable airflow assembly coupled to tip end of the lifting device. The variable airflow assembly includes at least one surface moveable between a plurality of positions having varying resistances so as to counteract the asymmetric loading.

A telescopic strut, in particular for a device for lifting loads, in particular for a hanger for vehicles or vehicle parts, wherein the telescopic strut consists of an outer tube and an inner tube guided therein, wherein the inner tube is movable longitudinal direction in the outer tube, where a number of sliding shoes are attached to the outer tube to guide the inner tube, where the sliding shoes have each been introduced from the outside into an opening in the wall of the outer tube and protrude inwardly to guide the inner tube such that the telescopic strut, which is structurally simple and therefore inexpensive to produce, has good sliding properties, has little guide play and is easy to maintain.

A telescopic strut, in particular for a device for lifting loads, in particular for a hanger for vehicles or vehicle parts, wherein the telescopic strut consists of an outer tube and an inner tube guided therein, wherein the inner tube is movable longitudinal direction in the outer tube, where a number of sliding shoes are attached to the outer tube to guide the inner tube, where the sliding shoes have each been introduced from the outside into an opening in the wall of the outer tube and protrude inwardly to guide the inner tube such that the telescopic strut, which is structurally simple and therefore inexpensive to produce, has good sliding properties, has little guide play and is easy to maintain.

An offshore transfer system includes an arm construction with a primary measurement system to measure and compensate for relative movement of an element relative to an external reference when the element is supported by the arm tip, as well as a secondary measurement system to measure and compensate for relative movement of the arm tip relative to the element when the element is put down and no longer supported by the arm tip.

A load guiding arrangement realized for mounting to a crane, which load guiding arrangement comprises a number of load guides, wherein a load guide comprises a guide wire extending from a lower level of the crane to an upper level of the crane; a bridging connector realized to bridge a gap between the guide wire and a control wire, which bridging connector is free to travel along the guide wire and the control wire according to a vertical displacement of a load; and a control wire extending from a lower level of the crane, through the bridging connector to a lifting connector for connecting to the load (4), and through the bridging connector again to an upper level of the crane is provided.

A load guiding arrangement realized for mounting to a crane, which load guiding arrangement comprises a number of load guides, wherein a load guide comprises a guide wire extending from a lower level of the crane to an upper level of the crane; a bridging connector realized to bridge a gap between the guide wire and a control wire, which bridging connector is free to travel along the guide wire and the control wire according to a vertical displacement of a load; and a control wire extending from a lower level of the crane, through the bridging connector to a lifting connector for connecting to the load (4), and through the bridging connector again to an upper level of the crane is provided.

A method for controlling a movement of a load in a workspace by a control device, including a) acquiring target coordinates to be set of a target point in the workspace towards which a load pick-up apparatus is to be moved, b) determining a load measured value by measuring the weight of the load using a load measuring device, c) determining actual cable lengths of positioning cables, d) determining desired cable lengths to be set by the respective positioning cable winch, for the positioning cables for the target coordinates of the target point to be set and for the current load measured value, and for each of the positioning cables, the control device searches a database for a data set that matches the target coordinates of the target point that are to be set and the current load measured value, and determines the desired cable length to be set.

Various embodiments of the teachings herein include methods for controlling a crane. The method may include: acquiring a first speed of a first motor pulling a first end of a hoist; acquiring a second speed of a second motor pulling a second end of the hoist opposite the first end; acquiring a first speed difference between the first speed and the second speed; acquiring a first speed difference threshold; and if the first speed difference is smaller than the first speed difference threshold, sending a control instruction to the first motor to increase a torque output value of the first motor in the trolley traveling direction.

An improved method for controlling a lifting device, which moves a load along a first movement direction and along a second movement direction within a specified working area of the lifting device from a starting point to an end point. Individual movements are planned for the first movement direction and for the second movement direction, by which the load is moved on while avoiding a collision with a changed or newly specified obstacle.