The self-contained energy efficient hydraulic actuator system of the present invention includes a hydraulic cylinder, a servo motor that is configured to produce rated torque from zero RPM to maximum rated RPM with rotor speed/position feedback to a servo motor, a pump, and a solenoid valve that enables the hydraulic cylinder to maintain its position without the motor running. The system has the ability to hold a load in place without motor operation via the use of the solenoid valve, and therefore saves energy and extends the motor lifetime by minimizing the motor running time.

A hydraulic control loop controls a hydraulic adjusting cylinder. The cylinder has a cylindrical housing and a displaceable piston therein. The piston divides the housing interior into a first and a second hydraulic chamber. A first hydraulic valve supplies the first hydraulic chamber with hydraulic fluid. A hydraulic pressure of the first hydraulic chamber is adjustable by controlling the first hydraulic valve. A second hydraulic valve supplies the second hydraulic chamber with hydraulic fluid. A hydraulic pressure of the second hydraulic chamber is adjustable by controlling the second hydraulic valve. A control device controls the two hydraulic valves. In a position control state, the second hydraulic valve is controlled by a position control signal dependent on the working position of the piston and the first hydraulic valve is controlled by an adjusted position control signal, that is generated on the basis of the position control signal.

A system (100), including: a fluidic actuator (2) which can be acted upon by a pressurized fluid and has an actuator member (3), a pressurized fluid provision device (4) which is adapted to carry out a position control of the actuator member (3) and, within the position control, to apply the pressurized fluid to the fluidic actuator (2) in order to move the actuator (3) into a prescribed position, the pressurized fluid provision device (4) being adapted to carry out the position control taking into account at least one system parameter, which describes a physical property of the system and/or a requirement parameter which defines a requirement for the positioning of the actuator (3), wherein the pressurized fluid provision device (4) is further adapted to perform an assistance procedure and to determine and/or verify, within the assistance procedure, the system parameter and/or the requirement parameter on the basis of a movement of the actuator (3) and/or a consideration of physical limits.

The pneumatic solar tracking system for solar panels adjusts the angular orientation of a solar panel to maximize exposure of an upper surface of the solar panel to incident solar radiation from the sun as the sun moves across the sky. The pneumatic solar tracking system includes a base and a platform supported above the base. The platform has an opening formed therein. A plurality of pneumatic actuators are supported on the base beneath the opening formed in the platform. The solar panel is supported on an upper surface of the platform, and a plurality of pivotal connectors pivotally connect the lower surface of the solar panel to respective pistons of the plurality of pneumatic actuators. Each of the pivotal connectors pivots along at least two orthogonal axes. An optical sensor is provided for detecting and tracking the angular position of the sun.

A hydraulic control loop controls a hydraulic adjusting cylinder. The cylinder has a cylindrical housing and a displaceable piston therein. The piston divides the housing interior into a first and a second hydraulic chamber. A first hydraulic valve supplies the first hydraulic chamber with hydraulic fluid. A hydraulic pressure of the first hydraulic chamber is adjustable by controlling the first hydraulic valve. A second hydraulic valve supplies the second hydraulic chamber with hydraulic fluid. A hydraulic pressure of the second hydraulic chamber is adjustable by controlling the second hydraulic valve. A control device controls the two hydraulic valves. In a position control state, the second hydraulic valve is controlled by a position control signal dependent on the working position of the piston and the first hydraulic valve is controlled by an adjusted position control signal, that is generated on the basis of the position control signal.

The self-contained energy efficient hydraulic actuator system of the present invention includes a hydraulic cylinder, a servo motor that is configured to produce rated torque from zero RPM to maximum rated RPM with rotor speed/position feedback to a servo motor, a pump, and a solenoid valve that enables the hydraulic cylinder to maintain its position without the motor running. The system has the ability to hold a load in place without motor operation via the use of the solenoid valve, and therefore saves energy and extends the motor lifetime by minimizing the motor running time.

A hydraulic system may include an electrohydraulic control valve disposed in fluid communication between a source of pressured fluid and a hydraulic actuator. The hydraulic system may be controlled to correct for offset errors between a target actuator pressure and a current actuator pressure output from the control valve, without amplifying pressure oscillations in the fluid between the control valve and the hydraulic actuator.

A milling machine may have a frame, a milling drum attached to the frame, and ground engaging tracks that support the frame and propel the milling machine in a forward or rearward direction. The milling machine may have height adjustable actuators connecting the frame to the tracks. Each actuator may have a cylinder attached to the frame, a piston slidably disposed within the cylinder, and a rod connected at a first end to the piston and connected to a track at a second end. The milling machine may have a tank storing hydraulic fluid and a fluid conduit connecting the tank to the cylinder. The milling machine may have a control valve selectively controlling a flow rate of the hydraulic fluid in the fluid conduit. The milling machine may also have a controller that determines a height of the frame relative to the ground surface based on the flow rate.

An actuation pressure to actuate one or more hydraulic actuators may be determined based on a load on the one or more hydraulic actuators of a robotic device. Based on the determined actuation pressure, a pressure rail from among a set of pressure rails at respective pressures may be selected. One or more valves may connect the selected pressure rail to a metering valve. The hydraulic drive system may operate in a discrete mode in which the metering valve opens such that hydraulic fluid flows from the selected pressure rail through the metering valve to the one or more hydraulic actuators at approximately the supply pressure. Responsive to a control state of the robotic device, the hydraulic drive system may operate in a continuous mode in which the metering valve throttles the hydraulic fluid such that the supply pressure is reduced to the determined actuation pressure.

Concrete product machine apron gap adjustment by actuating a gapper mechanism to set a desired gap between a reciprocally-movable apron plate and an interchangeably installable mold assembly installed in a concrete products machine. The gapper mechanism sets a desired gap between the machine apron plate and the mold assembly by injecting an index amount of hydraulic fluid into fluid communication with the rod side of a primary apron plate positioning cylinder, causing the machine's apron plate to retreat a desired gap distance away from an engaged position against the mold assembly.