Nuove architetture di controllo distribuito per automazione di macchine da lavoro e agricole

The topics described in this thesis are inherent to safety-relevant systems architectures for heavy-duty machines and new communication protocols between ECUs for agricultural machines. The first topic is about the study, design and implementation of a new communication protocol for agricultural machines capable of high throughput, reliability and dynamicity to realize advanced automation functionalities for precision farming, keeping compatibility for current communication standards. The study starts from the analysis of the current standard for communication (ISO 11783) and on its limits in terms of feasible functionalities, due to the physical layer, the CAN Bus. Migration to different physical layers is mandatory and it has been done in automotive, industrial and aeronautics world, using Ethernet Fieldbuses. Several solutions based on CAN and Ethernet are analyzed, which made the adoption of TCP/IP Stack preferable due to its flexibility and customization capabilities for different purposes. Some tests are performed, in order to evaluate TCP/IP Stack behavior with typical traffic between ECUs on agricultural machines. The results confirm the feasibility of using TCP/IP Stack with Ethernet as a valid solution for superseding CAN. Later, the TCP/IP stack has been improved to fulfil ISO 11783 requirements. A proof-of-concept has been realized, made of a hybrid network with the new high throughput protocol based on Ethernet on one side, and the older one based on CAN on the other. The second theme is about the design and validation of a system architecture for safety-relevant applications on heavy-duty machines. The approach is based on designing an architecture made of hardware and software components, which is general purpose for different application. This approach is in contrast with the one proposed by the safety standards (ISO 13849, ISO 25119, IEC 61508), but can achieve the same goals, increasing the re-use of validated architectures.