The development of an autonomous overhead traveling crane with real time path planning based on the potential method

This paper presents a method to establish real time path planning for three-dimensional (3-D) autonomous mobile overhead crane system. Proposed crane system consists of a visual system and a planning system. In the visual system, CCD image sensors, laser line markers and ultrasonic sensor (USS) are used to scan the transfer space. First, environmental map is generated by CCD image sensors and laser line markers. USS is used at on-line path planning that to renovate environmental map during the transferring in terms of the quick scanning time. This environmental map describes the transfer environment. Real time path planning is also established by expanding the off-line path planning and included in the planning system. Potential method is used as it's algorithm to develop updated Potential Field that describes the latest environment of transfer space. Transfer path is then constructed from the updated potential field and used for crane control references. The usefulness of proposed system is confirmed by the preliminary experimental results.