Electro-mechanical characterization of a walking beam transfer machine for flat glass applications Focus on mechanical validation and PLC programming

The global glass manufacturing market value was estimated at 262,30 billion euros in 2023 and is forecasted to increase at a compound annual growth rate of 7.5% from 2024 to 2032, as a consequence of the increasing adoption of smart and lightweight glass solutions, and growing trend of recyclable materials in the packaging sector. The main goal of this thesis project was to conduct an in-depth study of a “walking beam” transfer machine, adapted for custom flat glass applications. This peculiar typology of machine has been present for years in the catalogue of offers of Bottero s.p.a., a relevant player in the field, and it is often customised to satisfy and meet the specific and various criteria requested by different commissioners. Hence, the necessity of having a complete and general overview on the cinematic and dynamic behaviour of the machine and of its mechanics, as well as conscious knowledge about the dimensioning and verification of the components involved, with the purpose of unify and standardize them as much as possible to increase efficiency, simplicity and modularity. This study can be divided into two main parts: a mechanical characterization of the principal structures involved and the PLC software development and programming of the machine. In particular, the machine characterization focused on a precise analysis of the main mechanisms, as well as component evaluation and validation of the mechanical design, including dimensioning and stress analysis (Finite Element Method) of the most solicitated parts, along with a cinematic and dynamic study of the lifting and translating mechanism of the walking beam. The main goals were to provide a precise estimate of the motor torques necessary to achieve the requested performance and check whether the actual motor and components choices were overestimated or not in terms of load capacity and internal stress reactions. Moreover, a formulation of a general model for cinematic and dynamic tracking of the lifting and conveying processes was developed on Excel, so that it could be adapted to any machine adopting both or one of the same mechanisms, just replacing the parameters values with the current ones and obtaining a complete overview of the machine as an output. After having had a general overview of the PLC hardware and sensor system connected to the machine, the PLC software development consisted in an introduction to the program Studio 5000x by Rockwell Automation, together with a study of all motion control libraries available, followed by the motion programming in Ladder code through Motion Control techniques and Kinetix Motion. The libraries consented to download a set of kinetic parameters on the PLC controller of the walking beam to program the desired behaviour, including velocity profiles and motion sequence, in a single cycle routine, on the basis of simple input data provided by position sensors and HMI interactions i.e. push buttons. This programming section also includes the implementation of subroutines for emergency and other basic features that will be incorporated in the general architecture of the plant, along with a 3D simulation of the behaviour of the machine in CodeSys software environment through Factory I/O modelling app and on-field tests together with the automation department.