Collision-free robot coordination and visualization tools for robust cycle time optimization

Journal article, 2021

This paper presents novel algorithms and visualization tools for avoiding collisions and minimizing cycle time in multi-robot stations by velocity tuning of robot motions. These tools have the potential to support product/manufacturing engineers in the practical task of adding synchronization instructions to robot programs to overcome the challenges in terms of product design, cycle time, quality control, and maintenance including re-usability of coordination schemes. We propose a range of techniques to achieve that, when additional requirements make the best coordination strategy hard to be chosen. Indeed, our main contributions are (i) considering and minimizing delays introduced by limitation in hardware synchronization mechanisms, (ii) highlighting insights on the relationship between a 3D working space and a path coordination space, and (iii) a computational tool for visualization of shared areas in both work space and path coordination space. Different strategies based on the developed algorithms are evaluated by successfully automatically solving industrial test cases from inspection measurement applications in the automotive industry. A study about how cycle time robustness is significantly influenced by variation in the robot motion execution times is also given.