Mechatronic Solutions for the Safety of Workers Involved in the Use of Manure Spreader

An internationally acknowledged requirement is to analyze and provide technical solutions for prevention and safety during the use and maintenance of manure spreader wagons. Injuries statistics data and specific studies show that particular constructive criticalities have been identified on these machines, which are the cause of serious and often fatal accidents. These accidents particularly occur during the washing and maintenance phases—especially when such practices are carried out inside the hopper when the rotating parts of the machine are in action. The current technical standards and the various safety requirements under consideration have not always been effective for protecting workers. To this end, the use of SWOT analysis (Strengths, Weaknesses, Opportunities, and Threats) allowed us to highlight critical and positive aspects of the different solutions studied for reducing the risk due to contact with the rotating parts. The selected and tested solution consists of a decoupling system automatically activated when the wheels of the wagon are not moving. Such a solution prevents the contact with the moving rotating parts of the machine when the worker is inside the hopper. This mechatronic solution allowed us to obtain a prototype that has led to the resolution of the issues related to the use of the wagon itself: in fact, the system guarantees the stopping of manure spreading organs in about 12 s from the moment of the wheels stopping.