Robot system and method for coil packaging

A robot system comprising a robot control system, a cradle for carrying the coil, two industrial robots, each industrial robot being provided with at least one robot arm having a coupling robot piece configured to interface with a robot tool having two ends with each end being configured to interface with a coupling robot piece of a respective one of the at least one robot arms, and a roll holder shaft projecting substantially perpendicular to an axis extending between said two ends and carrying a roll of wrapping material, wherein said robot control system is configured to control the movements of the robots in relation to the coil in order to wrap the coil with the wrapping material in successive wrapping turns each comprising a sequence of robot movements including two handovers of the robot tool between the two robots per wrapping turn where a first handover phase takes place in a hollow cylindrical center core of the coil and a second handover phase takes place along a curved envelope surface of the coil, said robot control system is further configured to control the movements of the robots and their respective robot arm so that the application of the wrapping material to the surfaces of the coil is comprising at least one of:

• a. position, in three-dimensional space along and outside a first outer circumferential edge of the coil, the robot arm of a first robot holding the robot tool with the roll of wrapping material in a different position in three-dimensional space relative a corresponding position along and outside said first outer circumferential edge for the immediately preceding wrapping turn, and
• b. positioning the robot arm of the respective robots so that the longitudinal axis of the roll holder shaft of the robot tool holding the roll is directed in an inclined angular direction relative a direction of rotation of the coil, and
• c. moving the respective robot and robot arm holding the robot tool along the curved envelope surface so that a direction of travel for the respective robot and robot arm holding the robot tool with the roll so that the roll is travelling along the curved envelope at an angular direction within the angle range of 0.1 to 15 degrees relative an axis along the curved envelope surface which is parallel to a rotational axis of the coil.

A non-transitory computer readable medium, comprising:

• the computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, cause the at least one processor to implement and/or send control data for controlling the sequences of robotic movements of two robots for wrapping a coil in successive wrapping laps where a first handover phase takes place in a hollow cylindrical center core of the coil and a second handover phase takes place along a curved envelope surface of the coil,
• said computer readable medium is further configured to cause at least one of the following actions to be performed by the robot and robot arm holding a robot tool with the roll of wrapping material:
• a. positioning, in three-dimensional space along and outside a first outer circumferential edge of the coil, the robot arm of a first robot holding a robot tool with the roll of wrapping material in a different position in three-dimensional space relative a corresponding position along and outside said first outer circumferential edge for the immediately preceding wrapping turn,
• b. positioning the robot arm of the respective robots so that the longitudinal axis of the shaft of the robot tool holding the roll is directed in an inclined angular direction relative a direction of rotation of the coil, wherein the longitudinal axis of the shaft of the robot tool is positioned and maintained in a substantially constant angular direction within an angle range of 2 to 30 degrees relative the direction of rotation of the coil and a sub-area of the curved envelope surface to which the wrapping material is applied, and
• c. moving the respective robot and robot arm holding the robot tool along the curved envelope surface so that a direction of travel of the roll and the respective robot arm holding the roll along the curved envelope surface is in a direction at an angle relative an axis along the curved envelope surface which is parallel to a rotational axis of the coil, wherein the direction of travel for the respective robot and robot arm holding the roll along the curved envelope is in a straight direction at an angular direction within the angle range of 0.1 to 15 degrees relative an axis along the curved envelope surface which is parallel to the rotational axis of the coil.

A computer program product tangibly stored on a computer readable storage medium and comprising at least one processor and instructions which, when executed on the at least one processor, cause the at least one processor to implement and/or send control data for controlling the movement paths for two robots for wrapping a coil in successive wrapping laps where a first handover phase takes place in a hollow cylindrical center core of the coil and a second handover phase takes place along a curved envelope surface of the coil and including at least one of the following actions and sequence of movements by the respective robot and robot arm holding a robot tool with a roll of wrapping material:

• a. positioning, in three-dimensional space along and outside a first outer circumferential edge of the coil, the robot arm of a first robot holding the robot tool with the roll of wrapping material so that the roll is positioned in a different position in three-dimensional space relative a corresponding position along and outside said first outer circumferential edge for the immediately preceding wrapping turn,
• b. positioning the robot arm of the respective robots so that the longitudinal axis of the shaft of the robot tool holding the roll is directed in an inclined angular direction relative a direction of rotation of the coil, wherein the longitudinal axis of the shaft of the robot arm is positioned and maintained in a substantially constant angular direction within an angle range of 2 to 30 degrees relative the direction of rotation of the coil and a sub-area of the curved envelope surface to which the wrapping material is applied, and
• c. moving the respective robot and robot arm holding the robot tool along the curved envelope surface so that a direction of travel of the roll and the respective robot arm holding the robot tool with the roll along the curved envelope surface is in a direction at an angle relative an axis along the curved envelope surface which is parallel to the rotational axis of the coil, wherein the direction of travel for the respective robot and robot arm holding the robot tool with the roll along the curved envelope is in a straight direction at an angular direction within the angle range of 0.1 to 15 degrees relative an axis along the curved envelope surface which is parallel to a rotational axis of the coil.