These hydraulic cylinders are designed to use internal LVDT or magnetostrictive linear transducers. They can be provided with valve blocks complete with proportional valves, accumulators, servo valves, pressure transducers and load cells. This type cylinder does not require seals. The radial load on the rod is carried by a hydrodynamic oil cushion that prevents the rod from coming into contact with the cylinder head on which it slides. This technology allows friction to be reduced to a minimum, with speeds up to 20m\/sec and maximum frequencies that reach the limits of the control electronics and the response of the servo valve.<\/p>\n\n