Glass façades are widely used in modern buildings. Often, the glass panels used in such projects are difficult handle due to the large size and irregular shape. In particular, handling large glass sheets during the panel fabrication process presents many challenges, since the sheet is not encased in the frame. In this study we develop a strategy for vacuum lifting of such large, curved glass sheets via an optimization framework. The optimization is set up to to reduce the maximum stress on the curved glass panel as it is lifted by a small number of vacuum suction cups. The study is restricted to the case where the problem is a static one - i.e., the dynamic forces felt by the sheet during the lifting are negligible.

The mechanical structure of vacuum lifting systems is well developed an...[ Read more ]

Glass façades are widely used in modern buildings. Often, the glass panels used in such projects are difficult handle due to the large size and irregular shape. In particular, handling large glass sheets during the panel fabrication process presents many challenges, since the sheet is not encased in the frame. In this study we develop a strategy for vacuum lifting of such large, curved glass sheets via an optimization framework. The optimization is set up to to reduce the maximum stress on the curved glass panel as it is lifted by a small number of vacuum suction cups. The study is restricted to the case where the problem is a static one - i.e., the dynamic forces felt by the sheet during the lifting are negligible.

The mechanical structure of vacuum lifting systems is well developed and studied, as are the foundations of stress analysis in a static setting. The key contribution of this work is to find the optimal number of vacuum cups and their locations such that the maximum stress induced in the sheet (under gravity) as it is lifted vertically under quasi-static conditions is minimized. A commericial software (SolidWorks) is used to perform the stress computation. A modified Particle swarm optimization (PSO) algorithm is developed for solving our problem. Experiments were done to find the suitable parameters to reduce the optimization time and improve the result.

Based on the experimental data, the stress on the glass surface can be largely reduced by applying new PSO methods on the glass façades handling system. This research creates the foundation for developing a robotic handling system that will eventually plan the optimal way to transport fabricated sheets from the forming machine to the panel assembly station in the glass factory.