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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.

Losses reduction and oil flow optimization management in construction machines and, in general, in heavy duty vehicles are two of the most challenging missions of today fluid power research. One of the most promising ideas is to implement multiple hydraulic power sources but this requires a flexible pump switch system; in fact, depending on flow request and machine mode, one or more pumps can be switched to serve each actuator. To put into practice these concepts it is necessary to in-depth design the distribution system, through which hydrostatic transmissions supply the different loads. The new component here presented realizes the pump switch management, creating a matrix framework of the hydraulic flow connections. Putting this concept it into practice the new architecture is able to connect alternatively a pump to one actuator at a time providing also for cross connections, enabling different sources flow summation.

Performance requests and machine automation, in conjunction with new regulations for commercial and heavy duty vehicles, represent a difficult challenge for machine design. Machine control systems complexity and functional safety regulation, are complex requirements to deal with in new machines design. The paper describes a steering system design, of a 6 wheeled agricultural front articulated self-propelled machine, that must comply with new regulations in terms of functional safety. The vehicle steering is driven by an electro-hydraulic system, totally controlled using electronics; the rear wheels are independently steered and controlled. This architecture requires a highly functional safety performance level. The safety analysis of the system lead to a required performance level whose compliance is a challenging task, due to the software quality required, and to the cost of a fully redundant hardware, on both electronics and hydraulics side.

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.

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.

Alongside with the increasing vehicle complexity, the functionalities related to the safety, diagnosis and maintainability have become critical. The operators of special machines such as agricultural, mining, construction vehicles might be overwhelmed by this increased complexity and, as a result, operations for the recovery or maintenance of their vehicles become difficult. The Augmented Reality (AR) seems to be a very promising technology both if applied to traditional smart-phones or to the upcoming glasses, that has been just presented to the market by several manufacturers. This paper reviews some use cases of applications created in Institute for Agricultural and Earthmoving Machines (IMAMOTER) of the National research Council of Italy (CNR) engineers laboratories, which propose a novel approach for assisted maintenance, recovery or training.

Ethernet is by now the most adopted bus for fast digital communications in many environments, from household entertainment, to PLC robotics in industrial assembly lines. Even in avionic applications, new standards are fixing research results. In a similar way in automotive industry, the interest in this technology is increasingly growing, pushed forward by much research and basically by the need of high throughput, that high dynamics distributed control requests. In the world of heavy-duty machines various needs suggest to investigate for a possible Ethernet Network implementation for both real time control and services. On the other hand Bosch proposes the FlexCAN, CAN Flexible rate, but it seems a short term solution for today's congested networks.

Heavy duty machines have become more electronically sophisticated and in-vehicle electronics are growing in number and complexity, keeping pace with technology advancements. New machines implements (both mounted or trailed) and machine automation, demand this evolution, and thus a new way of designing on-board Electronic Control Units (hereafter ECU) is required. Moreover, the connectivity between vehicles, often extended to World Wide Web, and machine control and Working Session Task Controllers demand to become really distributed and executed in real time. So, integrated control systems ask for more performing distributed controls over networks, in order to better manage the machine torque and power and in order to optimize the fuel consumption, as a function of power request.