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Functional safety requirements and solutions are more expensive when it comes to lower cost machines with less power but same functionalities with respect to big machines. The paper will show a real Electronic Control Unit (ECU) design of a machine controller, controlling both engine working point, transmission, and other utilities like PTO, 4WD, brakes and Differential Lock; the ECU was designed in accordance to ISO 25119 regulation, to meet AgPL = C or even D for some functionalities. The unit is a fully redundant electronic control unit with two CAN networks and some special safe state oriented mechanism, that allow the Performance Level C with less software analysis requirements compared with traditional solutions. All safety critical sensors are redounded and singularly diagnosable, all command effects are directly observable and most of commands are directly diagnosable.

Stationary (parking) brake is a very important and safety critical function in many classes of machines. The new transmissions and the “by wire” systems increase the criticality of the role of stationary brake, as it is also an emergency (secondary) brake, and it’s often used to hold the vehicle when the transmission is not locking the wheels. As an example, dual clutch and power-shift transmission gear systems, as well as hydrostatic transmissions under certain circumstances, are often unable to hold the vehicle stopped and this function is provided by the stationary brake. Due to the main need of having the brake actuated when vehicle is stopped, without any hydraulic and electric power, the brake configuration is normally a “negative” configuration, usually called “spring applied” because of the actuator configuration, but this configuration causes the brake actuation when de-energized, even in case of system failure.

Automotive industry compartment is undertaking a massive technology revolution. ADAS systems and infotainment promise to change the way that customers mean travel and transportation radically, through several use cases. The key enabling technologies for this trend are Ethernet and its newly standardized physical layer, IEEE 802.3bw 100BASE-T1 (a.k.a. BroadR-Reach). From an architectural point of view, the evolution of the applications that rely on Automotive Ethernet resembles in many ways the evolution that the IT has had in the last decades. In the IT world, increased throughput and computational power to the end-user enabled technologies like multimedia streaming; scalability and availability requirements, together with the increased complexity of IT infrastructure, led to the “Anything as a Service” paradigm and Software Defined Networks.

The new X-by-Wire systems under study for commercial and heavy-duty vehicles, as well as for Agricultural Tractors, are increasingly real autonomous systems, capable to autonomously control a vehicle functionality, actuating the operator's commands, or managing in a complete autonomy a machine function. These application need an higher Performance Level from the functional safety point of view, due to the risk of a malfunction consequence. The paper deals with a new concept hydraulic spool valve that allow the design of new safer and more compacted hydraulic circuit architectures, ensuring higher safety performance levels. The architecture presents advantages both from performance (precision, fastness), both from operational point of view. The paper will focus in particular on safety and control topics. The new patented valve presents a secondary rotary type actuator connected to a sleeve interposed between the spool and the valve body, thus composing a roto-translating valve.