Collision-free guidance of a load suspended from a cable

A method for operating a crane, in particular a container crane, with a control facility of the crane, the method comprising:

• suspending a load from an upper load suspension point via a cable system so as to enable the load to swing around the upper load suspension point,
• controlling drives of the crane configured to move the upper load suspension point and the load,
• when moving the upper load suspension point, dynamically determining an inner safety zone around the load repeatedly as a function of state variables of the crane, with the state variables comprising at least a position of the upper load suspension point, a travel speed of the upper load suspension point and an effective pendulum length of the load around the upper load suspension point,
• checking, based on further information known to the control facility, whether an object different from the load is entering the inner safety zone, and
• when an object different from the load enters the inner safety zone, stopping moving the upper load suspension point or outputting to an operator of the crane a message to stop moving of the upper load suspension point, and
• otherwise continuing moving the upper load suspension point or not outputting to the operator of the crane the message to stop moving of the upper load suspension point.

A computer program product for a control facility controlling a crane, which carries a load suspended from an upper load suspension point via a cable system so as to enable the load to swing around the upper load suspension point, the computer program product embodied in a non-transitory computer-readable medium and comprising machine code which, when loaded into a memory of a processor of the control facility and executed by the processor, causes the control facility to operate the crane by:

• controlling drives of the crane configured to move the upper load suspension point and the load,
• when moving the upper load suspension point, dynamically determining an inner safety zone around the load repeatedly as a function of state variables of the crane, with the state variables comprising at least a position of the upper load suspension point, a travel speed of the upper load suspension point and an effective pendulum length of the load around the upper load suspension point,
• checking, based on further information known to the control facility, whether an object different from the load is entering the inner safety zone, and
• when an object different from the load enters the inner safety zone, stopping moving the upper load suspension point or outputting to an operator of the crane a message to stop moving of the upper load suspension point, and
• otherwise continuing moving the upper load suspension point or not outputting to the operator of the crane the message to stop moving of the upper load suspension point.

A crane, in particular a container crane, comprising:

• a cable system having an upper load suspension point from which a load is suspended so as to enable the load to swing around the upper load suspension point,
• at least one drive configured to move the upper load suspension point and the load, and
• a control facility configured to
• control the at least one drive so as to move the upper load suspension point and the load commensurate with control commands from the control facility,
• when moving the upper load suspension point, dynamically determine an inner safety zone around the load repeatedly as a function of state variables of the crane, with the state variables comprising at least a position of the upper load suspension point, a travel speed of the upper load suspension point and an effective pendulum length of the load around the upper load suspension point,
• check, based on further information known to the control facility, whether an object different from the load is entering the inner safety zone, and
• when an object different from the load enters the inner safety zone, stop moving the upper load suspension point or output to an operator of the crane a message to stop moving of the upper load suspension point, and
• otherwise continue moving the upper load suspension point or not output to the operator of the crane the message to stop moving of the upper load suspension point.