Crane arrangement and a method for control thereof

A crane arrangement (2) comprising

• a crane base (7);
• a crane pillar (8) rotatably arranged to the crane base (7),
• a crane boom system (3) comprising a plurality of crane booms (4, 5) pivotally arranged in relation to each other, said crane boom system (3) having a first end (13) pivotally arranged at an end of the crane pillar (8) and a second, free end (14), wherein at least one of the plurality of crane booms (4, 5) is extendable/retractable,
• a crane tool assembly (10) arranged at the second, free end (13) of the crane boom system (3);
• a plurality of actuators (6) arranged to
• control extension/retraction of the at least one extendable/retractable crane boom,
• control a rotational position, v5, of the tool around its rotation axis, z_r, control a slewing angle, v1, of the crane pillar,
• control a pivotal angle, v2, between the crane pillar and the crane indicator (11),
• boom system, and
• control a pivotal angle, v3, between the crane booms (4, 5) pivotally arranged in relation to each other,;
• wherein said crane tool assembly (10) comprises a tool (9) having a direction said crane arrangement (2) further comprising
• a crane controller (200) for control of movement of the crane tool assembly (10) arranged at the second, free end of the crane boom system, said crane controller being arranged to receive a directional command for rotational displacement of the tool around its rotation axis, z_r, from an initial pointing direction, x0, of the direction indicator (11) of the tool (9) and to based thereon control at least one of said plurality of actuators to perform displacement of the tool around its rotation axis, z_r according to the directional command to a desired pointing direction, x1, of the direction indicator, said crane controller further being arranged to receive a drive command for movement of the crane tool assembly and to control at least one of said plurality of actuators to perform movement of the crane tool assembly along the desired pointing direction, x1, of the direction indicator (11) of the tool (9).