Protocol for dialogue between tractor and implement, interoperability scheme between different machines, manufacturer-independent universal terminal: the definitions for Isobus are endless.
Ottavio Repetti
Beyond the many years that have passed since its introduction, Isobus remains a project in constant evolution and as such needs moments of reflection, comparison and fine-tuning. For example, the interconnection between different brands, which should be an established fact by now, does not always happen on the first try and without hindrance. The reason?
Sometimes, not even the experts in the field are familiar with it, because the Isobus protocol, enriched month after month with new functions, is becoming a complex system, and in such complexity, an uninterpreted code, information written differently (implement side or tractor side, so the possibility of error doubles) is enough to create problems. With the aggravating factor that, unlike a mechanical fault, finding out where the stumbling block is in software that does not respond as it should is not a simple matter.
A Meeting Point
Fortunately, there are structures that are concerned with precisely this, namely harmonising, improving and constantly implementing the Isobus protocol, making it a truly universal standard. At a European level, the body that has taken on this task is Aef (Agricoltural Electronic Foundation), a foundation that has its Italian counterpart in Rei (Reggio Emilia Innovazione), an organisation that manages the Isobus Certification Laboratory, one of the five existing, at a global level, for the validation of equipment and terminals according to the principles of Aef. In essence, an Isobus system tested and certified in the Emilia laboratory should give the maximum guarantee of smooth operation and dialogue with all Aef-certified systems, whether Italian, European or worldwide. This is because these devices meet certain requirements that Aef has identified as essential for the connection between machines to take place with the simple insertion of the plug into the appropriate socket. In essence, it is a kind of very well detailed Isobus, where the pure and simple Isobus standard leaves a certain freedom of interpretation to the various manufacturers who, in the past, have proposed slightly modified versions, and for this reason proprietary, not always suitable for communication with all the devices on the market.
A moment of confrontation
A valuable and interesting moment of confrontation is the Virtual Terminal Day, organised by the Ideagri network, of which Rei is a member, and hosted in the premises of the Rei foundation, in Reggio Emilia. Here, where control units and terminals are tested, machine and software manufacturers, associations such as Federunacoma and Rei itself met to take stock, together, of the state of Isobus and the next steps indicated by Aef. Among them, the second generation of Tim, the Isobus function that allows the implement to take control of the tractor and which, with a bit of imagination, can be seen as the first step towards a worksite without human presence.
The evolution of Tim
Tim stands for Tractor implement management, or the possibility that, thanks to the Isobus network, the implement manages certain functions of the tractor. The classic example – but also the most common in reality – is the baler that adjusts the speed of the tractor according to the working load and the need to stop to eject the bale (we are talking about round balers, in this case). «Tim at the moment is mainly used on balers and round balers, seed drills and generally machines that need to regulate the speed and hydraulics of the tractor, as well as steering», explained Andrea Pavesi, technician at Rei.
Although it has only been active for just a few years, Tim is already under scrutiny and the new version (Tim 2) is being discussed. It should introduce some purely technical changes, such as determining the type of transmission, managing any tampering of control messages and the like, but also elements that are much more interesting for ordinary mortals, such as the management of the inclination of an implement via the hydraulic distributors, which is very useful when it is necessary to keep a constant height from the ground of a mowing bar or sprayer wing, for example. «The current automatic systems for controlling the inclination of an implement work outside of Isobus. The idea would be to integrate the new height adjustment systems into Tim, so that fewer and fewer functions work outside Isobus and thus simplify implement electronics», explained Pavesi. Also under discussion for Tim version 2 is the introduction of a protocol dedicated to equipment with high-power electric drive: a path towards which the new agricultural mechanics seems to be heading.
Beware of cyber-attacks
An element to which little attention is paid, but which could soon become very relevant, is that of cyber-security: an issue on which Europe has decided to intervene in a very incisive manner. And the fallout, as we shall see, could also be important in the agricultural sector. «Faced with a significant growth in cyber attacks, the EU has issued the Cyber Resilience Act, abbreviated Cra», explained Federunacoma’s digital agriculture manager, Alessio Bolognesi. The European regulation, which is in the process of being adopted, is expected to become operational starting in 2027. « From that date onwards, all electronic devices that will be placed on the market, if they involve any form of remote communication, must be protected against cyber-attacks ». It is up to the manufacturer, continued Bolognesi, to certify that their products are safe. But what does “safe” mean? Unfortunately, the definition is rather broad: «In practice, the manufacturer certifies that its product has no known vulnerabilities; in other words, it must not be attackable by a hacker in any way known at the time of manufacture. It is therefore up to the manufacturer to assess and possibly prevent any possible source of attack by a hacker». This prevention, Bolognesi specified, may mean the revision of a part of a device’s connection software or even its entire architecture, depending on the severity of the vulnerability identified.
Isobus and hackers
This covers every electronic device, from the PC to the mobile phone, from the oven with Wi-fi to the robot that cuts the grass in the garden. «If an object is equipped with a connection system of some kind, it falls under Cra», Bolognesi sentenced. Transposed to agriculture, the cyber resilience law will presumably apply to all new-generation tractors «which will therefore have to be Safety, i.e. safe for the operator, and Secure, i.e. free from intrusions», the Federunacoma technician concluded. Still to be clarified is the situation regarding equipment. «In Aef they are analysing the text of the regulation to see to what extent the Isobus protocol falls under Cra. Certainly functions like Tim, Hsi (High Speed Isobus), Wic (Wireless in field communication) and AgIn (the new data exchange protocol, nda) are under scrutiny in Aef». The problem, concluded the speaker, could arise if all the most widespread Isobus functions were to require a security certificate: «There is a real risk, in that case, of an overload of the Bus network».
Towards the nets in the field
In a process of constant updating, Isobus clocks up one version after another. «Virtual Terminal is now at version 7, while Ut (universal terminal) is in its third generation», Pavesi pointed out. In the future, however, there is the transition from tractor-implement inter-operability to wireless communication between machines in full autonomy, as part of an evolution towards ever greater automation. While waiting to learn about the wonders of autonomous machinery, it is evident that interest in Isobus and its potential is growing steadily. In fact, among the audience there were several manufacturers who have not yet exploited the protocol for their machines, but intend to do so in the near future. Among them, important names, but also many micro-companies working in the field of electronics (boards and control units) or the retrofit of old machines. It is from the latter that the indispensable direct experience comes: the only one, after all, that can tell to what extent Isobus connectivity really keeps its promises.
Gaps to fill
«Gaps remain on very specific equipment, such as trimmers, defoliators and other machines for specialised crops », explained Stefano Quadraccia, director of Qs Control, an Umbrian company that makes Isobus systems for equipment such as ploughs, subsoilers, mower-conditioners and seeders. «The problem – Quadraccia explained – is related to the number of DDIs entered in the individual systems. At the Aef library level there are DDIs for almost everything; unfortunately, however, tractor manufacturers only include the most common ones in their software, such as speed, hectares worked, fuel consumption and so on. Information such as working depth and working height, for ploughs and mowing bars respectively, is often absent. If a tractor does not have a specific DDI, say for working height, it will not be able to manage this information on the virtual terminal». DDI (Data Dictionary Isobus) refers to the codes that each manufacturer can request to be included in the list of commands processed and recognised by Isobus systems. There is therefore a code for each parameter detected, from the width of the implement to the volume of crop distributed, from the distance between rows to the seeding depth. However, it is necessary that both implement and tractor have DDI information so that the value can be displayed on the universal terminal of the implement.
