In this paper the optimization of the spool and housing geometry in a small hydraulic switching valve to enable
the reduction of the axial flow forces to a minimum value is described. Non-optimized valve geometry is usually
the main cause for many problems related to response time, actuation force and energy consumption. To
overcome these limitations we have done a thorough numerical and experimental analysis focused on fluid flow
forces. The results show that the axial flow forces can be reduced significantly just by modifying the geometry of
the valve spool and housing. Thus the valve dynamic characteristics can be significantly improved.

In automatic and dual clutch transmissions, electromagnetic solenoids and valves are required, which have high
requirements for the magnetic force profile and in particular on the magnetic force hysteresis. While there are
rising numbers of gears and shifting operations in the transmission, these parameters help to increase the
efficiency of the whole transmission and consequently lead to a reduction of fuel consumption and emissions.
The aim of the development was to increase the power density of such solenoids, by further minimization of the
magnetic force hysteresis and by setting an economic benchmark. Furthermore, the goal was to develop a
flexible standardization of these components, which enables an easy adaption to various customer requirements
while offering a cost efficient production on a multi-product line.

Water hydraulic proportional control valves are a novel fluid control device using water as the working fluid. They are very hygienic and eco-compatible, permit high-output control, and have applications in many industries. Previously, the authors expressed its characteristics as a third-order transfer function including a compensation circuit (with spool displacement as a control parameter), solenoid, and pilot valve, and examined the effects of design parameters on frequency characteristics, step response, and system stability. Here, its characteristics are examined in the non-linear region by introducing the non-linearity of the control apertures and damping orifice. The results demonstrate the feasibility of applying a linear model in this region.

LiView® is an innovative stroke transducer for hydraulic cylinders, that is based on the electrical measurement of
the cylinder structure in order to gain information on the piston absolute position and speed. In our paper we
present the main characteristics of the LiView® product, the achieved results in the last two years of
development and we discuss the performance of the system as measured throughout the many test campaigns run
both at cylinder and machine level in the first target customer applications. Moreover, the implications deriving
by the use of this technology on hydraulic systems are discussed, showing its disruptive potential for future
machines.