A rotary actuator includes a central housing; an output shaft that extends through the central housing; a vane that is mechanically coupled to the output shaft and divides the central housing into a first chamber and a second chamber; and a flow control mechanism that is moveable within the central housing and including a high pressure port and a low pressure port for communicating hydraulic fluid into and from the first and second chambers. The flow control mechanism is moveable to position the high pressure port and low pressure port relative to the first chamber and the second chamber for communication of the hydraulic fluid, thereby generating a pressure differential across the chambers. The vane rotates within the central housing in response to the pressure differential, and rotation of the vane drives the output shaft. A motor is configured to receive control signals to drive the movement of the flow control mechanism.

A slewing-type working machine includes: a slewing motor which is a hydraulic motor for slewing; a variable-displacement hydraulic pump; a slewing operation device including an operation member; a control valve controlling the slewing motor based on an operation signal thereof; a pump regulator; a relief valve letting excess fluid to a tank; operation detectors detecting an operation direction and amount of the operation member; a motor rotational speed detector; and a controller controlling a discharge flow rate of the hydraulic pump. The controller obtains a deviation between a target rotational speed of the slewing motor obtained from a slewing operation amount and an actual rotational speed detected by the motor rotational speed detector, and controls the discharge flow rate to make the deviation closer to 0.

A lift apparatus includes a lift assembly and a servo-control system. The lift assembly includes at least one pneumatic actuator including a movable member to provide a load to transfer a substrate between a support and a transfer plane. The lift assembly further includes at least one proportional pneumatic valve to control fluid flow between the actuator and a pressurized fluid supply or a vent, a plurality of pressure sensors each to measure pressure in a respective supply line to the actuator, and at least one position sensor to measure a position of the movable member. The servo-control system includes a controller to determine an output force based on a commanded force and an estimated force, generate a control signal based on the output force, and apply the control signal to the proportional valve to move the movable member.

A hydraulic system is provided with a pump supplying pressurized hydraulic fluid through a first supply line to a closed center control valve. From the control valve the fluid is directed through work lines to a hydraulic motor. Exhausted hydraulic fluid from the hydraulic motor is directed through the control valve to an exhaust line having a back pressure check valve set at a first pressure level. To keep the exhaust line fully charged a second supply line extends between the first supply line and the exhaust line. The second supply line is provided with a pressure reducing valve that is set at a second pressure level that is greater than the first pressure level of the back pressure check valve. An oil conditioning circuit is disposed between the back pressure check valve and a return tank for persistent hydraulic fluid conditioning.

A hydraulic system is provided with a pump supplying pressurized hydraulic fluid through a first supply line to a closed center control valve. From the control valve the fluid is directed through work lines to a hydraulic motor. Exhausted hydraulic fluid from the hydraulic motor is directed through the control valve to an exhaust line having a back pressure check valve set at a first pressure level. To keep the exhaust line fully charged a second supply line extends between the first supply line and the exhaust line. The second supply line is provided with a pressure reducing valve that is set at a second pressure level that is greater than the first pressure level of the back pressure check valve. An oil conditioning circuit is disposed between the back pressure check valve and a return tank for persistent hydraulic fluid conditioning.

Various embodiments of the present disclosure provide a rotorcraft-assisted system and method for launching and retrieving a fixed-wing aircraft into and from free flight. The launch and retrieval system includes a modular multicopter, a storage and launch system, an anchor system, a flexible capture member, and an aircraft-landing structure. The multicopter is attachable to the fixed-wing aircraft to facilitate launching the fixed-wing aircraft into free, wing-borne flight. The storage and launch system is usable to store the multicopter (when disassembled) and to act as a launch mount for the fixed-wing aircraft by retaining the fixed-wing aircraft in a desired launch orientation. The anchor system is usable with the multicopter, the flexible capture member, and the aircraft-landing structure to retrieve the fixed-wing aircraft from free, wing-borne flight.

Various embodiments of the present disclosure provide a rotorcraft-assisted system and method for launching and retrieving a fixed-wing aircraft into and from free flight. The launch and retrieval system includes a modular multicopter, a storage and launch system, an anchor system, a flexible capture member, and an aircraft-landing structure. The multicopter is attachable to the fixed-wing aircraft to facilitate launching the fixed-wing aircraft into free, wing-borne flight. The storage and launch system is usable to store the multicopter (when disassembled) and to act as a launch mount for the fixed-wing aircraft by retaining the fixed-wing aircraft in a desired launch orientation. The anchor system is usable with the multicopter, the flexible capture member, and the aircraft-landing structure to retrieve the fixed-wing aircraft from free, wing-borne flight.