Systems for the operational monitoring of agricultural machinery
The technical control of the company's machinery has assumed great importance, both for the traceability of particularly delicate processes, and to allow remote maintenance interventions in real time, resolving situations that would otherwise lead to long periods of machine downtime
The agriculture of the new millennium must face rapidly changing economic, social and environmental scenarios, which require technological innovations aimed at creating low-impact and low-cost crop systems, forms of advanced management aimed at optimizing labour productivity and reducing production costs, as well as the production of appropriate documentation for the purpose of complete traceability to protect the consumer and the environment. Achieving these goals is now possible with the techniques of precision agriculture, through which individual mechanised operations are not only managed automatically, but which represents a truly advanced form of farm management.
Operational monitoring. This area undoubtedly includes operational monitoring, i.e. the possibility of collecting data, storing them and processing them in a company information system in order to reconstruct and track all the mechanised activities carried out in the company, thus creating a historical archive of the processes carried out and, more recently, also allowing the company to manage its machine fleet according to telemetry logics, which until recently was only possible in the automotive sector. The activation of operational monitoring is rather complex, not so much because of the inherent difficulties, but because of the need to systematically organise the activities of recording events carried out on a typically irregular basis, often subject to changes in scheduling and usually delocalised over vast portions of territory, with the consequent impossibility of immediately verifying the state of execution of works. For this type of monitoring, identification processes prevail over measurement processes. In fact, in order to completely reconstruct the status of an event, in addition to the time aspects (date and duration, possibly divided into work phases), the main actors involved must be identified: tractor, operator (i.e. type of work carried out), performer (not compulsory, for privacy reasons), place of work, amount of work performed, any materials involved (collected or distributed).
The historical archive of mechanised operations, now present in most commercial software designed for business management, offers numerous advantages. First of all, it is possible to have the actual technical itinerary followed for the cultivation of any product grown on the farm over several years, making it possible to make agronomic choices weighted according to the real production results (positive, or more often negative) obtained in certain particular years. The resulting database can be queried, as well as by year, also by plot and/or by crop. This facilitates the calculation of production-related costs, moving from estimates (however reasonable) to actual values, enabling the drawing up of an essentially analytical final balance sheet. A further possibility is to know, with a high degree of detail, how one's own fleet of machines is used in terms of hours actually worked, both for tractor units and for operating machines, with the corresponding fuel consumption and division of working time.
In this case, it is possible to make an accurate profit and loss account for each machine, being able to assess not only its impact on the company's budget, but also its actual utilisation. Thanks to this technology, it is possible to perform technical analyses that are based on the calculation of computed synthetic indices, starting precisely from data actually measured in the field, such as the power utilization coefficient, which represents the optimal exploitation of the power available for the equipment, or the hourly utilization coefficient, i.e. the achievement of the maximum useful life value of the tractor before it is technologically obsolete.
The traceability. With regard to traceability, which may concern individual processes (for example the distribution of plant protection products or livestock manure) or entire production chains, the possibility of having an archive of processes based on safe and objective data leads to the updating and almost complete compilation of reports, in accordance with current legislation (treatment register, field notebook) or the fulfilment of the obligations provided for by specific production regulations. It is intuitive how such computerized management requires the automatic recording of the field data of the machines involved, as well as the ways in which such data is transferred to the company database. Although possible in emergencies, manual data transfers (e.g. via USB sticks or other memory cards) are highly discouraged as a common practice, due to their poor reliability. A successful solution concerns the transmission of data to servers via a wireless network or, more recently, via the cloud. This has the further advantage that the system can operate in real time and therefore can also perform the function of a fleet control tool.
To date, except in special cases where dataloggers specially developed for retrofitting installations can be used, the acquisition of data takes place through electronic systems connected to the ISOBUS line of tractors, making use of the large amount of data already acquired by the on-board CAN network and integrating operational monitoring activities with automation activities.
Telemetry. There are more and more manufacturers of tractors and self-propelled machines that offer, usually as an option, a monitoring system for the purpose of maintenance and remote resolution of any mechanical problems. Various levels of telemetry are available, at an increasing technological level, and consequently of costs. The simplest monitoring solution concerns the position of the machine and its movements in the field and on the road: in this case, a satellite receiver with low accuracy and good precision is sufficient, which among other things finds application as an elementary control of the vehicle fleet, but also as an anti-theft system. In the most complete version, the monitoring system is able to measure, in addition to the current position of the vehicle, also the main operating parameters of the work in progress, such as - for example - the type of operating machine combined with the tractor, the feed speed, the engine load, the instantaneous and hourly fuel consumption, the operating temperatures, the temperature and pressure of the lubrication oil, the performance parameters of the machine and any parts subject to automatic or manual adjustment by the operator.
It is obviously a system that, in addition to allowing complete operational monitoring of the activities, allows the current operating status of the machine to be evaluated, identifying critical situations and any malfunctions. In this case, packages can be implemented that allow remote assistance and/or so-called "predictive" telemetry by the assistance service. Both functions are made available (usually following the payment of an annual or multi-year license) by the main manufacturers of tractors and self-propelled machines. Remote assistance consists of the possibility, on the part of the relative service, of remotely intervening on some electronic components of the machine, resolving a possible malfunction in real time or suggesting to the operator, in the most critical cases, the behaviour to be taken to safeguard the machinery while waiting for the necessary intervention.
In addition, since these systems are connected to the diagnostic socket of the tractor (similar to the OBD2 port on cars), after the fault is identified, the service department can quickly order the component to be replaced, thus greatly reducing machine downtime.
Predictive telemetry makes it possible to identify a possible fault, thus preventing it from occurring. This logic, called "mission profile", is still being studied, but it seems very promising, with a view to preventive maintenance. Moreover, albeit limited to ordinary operations, this function is already active thanks to the on-board computer (in perfect analogy with what has long been found in the automotive sector), which on the basis of predefined timeframes notifies the operator that the time to do the so-called "servicing" is approaching, so that the workshop can program the interventions in advance, keeping the machine in efficiency.
Among other things, the possibility of replacing a mechanical or electronic component before it actually fails can prevent the damage of parts connected to it, thus reducing the amount of intervention in both economic and temporal terms. These telemetry systems can allow the assistance to assume, albeit momentarily, control of the tractor, connecting and interacting with the on-board terminal.
It is therefore understood that the technological level must be particularly high, being fully justifiable and economically sustainable especially for high-end tractors and large self-propelled harvesting machines.
