Abstract: A digital hydraulic system including a fluid having three portions each at a pressure and a digital hydraulic transformer having a first and second element. The first element has a first end and a second end. The first and second elements operating along a common axis, and together defining at least four variable volume working chambers. The at least two of the at least four variable volume working chambers containing fluid directing force on the second element in a direction toward the first end. Another two of the at least four variable volume working chambers containing fluid directing force on the second element toward the second end. A control system individually selectively fluidically connects and disconnects each of the four variable volume working chambers to and from the three portions of the fluid at the three pressures.

Abstract: A control system for a work machine having a hydraulic energy source, a hydraulic accumulator, a digital hydraulic system having a digital hydraulic transformer, a hydraulic actuator and a movable element. The hydraulic accumulator being fluidically couplable with the hydraulic energy source. The digital hydraulic system including a digital hydraulic transformer fluidically couplable with the hydraulic accumulator. The hydraulic actuator being fluidically couplable with the digital hydraulic transformer. The movable element being movable by the hydraulic actuator. The control system including means to estimate at least one of potential energy and kinetic energy in the movable element; means to measure a fill level of hydraulic fluid in the hydraulic accumulator; and means to vary the amount of hydraulic energy added to the hydraulic accumulator by the hydraulic energy source responsive to the potential energy, the kinetic energy and/or the fill level of the hydraulic accumulator.

Abstract: A control system for a work machine having a hydraulic energy source, a hydraulic accumulator, a digital hydraulic system having a digital hydraulic transformer, a hydraulic actuator and a movable element. The hydraulic accumulator being fluidically couplable with the hydraulic energy source. The digital hydraulic system including a digital hydraulic transformer fluidically couplable with the hydraulic accumulator. The hydraulic actuator being fluidically couplable with the digital hydraulic transformer. The movable element being movable by the hydraulic actuator. The control system including means to estimate at least one of potential energy and kinetic energy in the movable element; means to measure a fill level of hydraulic fluid in the hydraulic accumulator; and means to vary the amount of hydraulic energy added to the hydraulic accumulator by the hydraulic energy source responsive to the potential energy, the kinetic energy and/or the fill level of the hydraulic accumulator.