Methodology and decentralised control of modularised changeable conveyor logistics system

ABSTRACT

To comply with the trend of customised production, this paper proposes a novel methodology for a changeable logistics system on certain factory scenes. By modularising the traditional conveyor belt system and applying decentralised control to each module, the changeable conveyor system can quickly reassemble itself for different logistics routes and thus react to the changing requirements of new production plans. The logistics route transformation is organised in two stages while reassembling. First, the modules calculate their paths on their own towards the assigned positions using a modified Rapid-exploring Random Tree (RRT) algorithm with the introduction of orientation factor (α-factor) to increase path smoothness; then a sensor-based Artificial Potential Field (APF) algorithm is applied for real-time collision avoidance with the sensor orientation and data weight being specially arranged. Through these two stages, the proposed system can flexibly react to changing logistics demands and form various logistics routes in the factory layout according to customised production requirements. Simulations and comparisons are given to illustrate the performances of the method.

KEYWORDS:

• Changeable logistics system
• modularisation
• decentralised control
• α-Rapid-exploring Random Tree (α-RRT)
• Sensor-based Artificial Potential Field (SAPF)

Acknowledgments

This work is supported by National Natural Science Foundation of China (Grant No. 71471139), Zhejiang Provincial Natural Science Foundation of China (Grant No. LY14E050020), MITT Intelligent Manufacturing Project of China “The study of interconnection standard and experimental verification in the intelligent manufacturing plant for naval architecture and marine engineering”.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Ministry of Industry and Information Technology of the People’s Republic of China; National Natural Science Foundation of China [71471139]; Natural Science Foundation of Zhejiang Province [LY14E050020].