An apparatus including a pneumatic system; an energy harvesting unit configured to generate electrical energy from a compressed gas in the pneumatic system; a battery connected to the energy harvesting unit; a sensor disposed to detect a first parameter regarding operation of the energy harvesting unit; and a controller connected to the sensor and the energy harvesting unit. The sensor and the controller are powered by the energy harvesting unit. The controller is configured to control the energy harvesting unit and to process measurements for the first parameter detected by the sensor. The controller is further programmed with a learning system configured to diagnose an operational condition of the energy harvesting unit based on the measurements for the first parameter, and to issue a command to the controller based on the operational condition.

A diagnostic apparatus for a fluidic actuator, in particular a fluidic valve drive, which has an actuator element displaceable into different positions (x1, x2, xp1, xp2), wherein the diagnostic apparatus is configured to provide a first break-away pressure measured value (pi1) for a first position of the actuator element. The diagnostic apparatus is further configured to determine, based on the first break-away pressure measured value (pi1) and break-away pressure reference information (pri) stored in the diagnostic apparatus, a first break-away pressure prediction value (pp1) for a first prediction position (xp1) of the actuator element, the first prediction position being different from the first position (x1).

The present disclosure relates to a system for monitoring a solenoid operated valve including at least one coil and at least one spool. The system compares a normalized current signature and a normalized current signature comparator to determine a spool fault condition.

A monitoring device and a method for determining operating health of a pressure medium operated device. The monitoring device is configured for processing input measuring data relating to operation of the pressure medium operated device. An operating condition value is determined in the monitoring device, where after the operating condition value is compared to an input reference data in order to determine current operating health. The reference data is determined by utilizing strength analysis, which is executed for a design model of the associated pressure medium operated device.

A method for controlling a cylinder includes providing a cylinder having a piston, a servo valve and a measuring device having at least one first position sensor and one second position sensor, measurements are taken of the position of the piston in the cylinder body simultaneously with the first position sensor and the second position sensor, at least one first displacement speed of the piston is determined on the basis of the piston position measurements obtained with the first position sensor, at least one second displacement speed of the piston is determined on the basis of the piston position measurements obtained with the second position sensor, and each of the first and second determined displacement speeds of the piston are compared with a modelled or predetermined displacement speed of the piston, in such a way as to identify the most reliable position sensor.

An excavator includes a hydraulic oil holding circuit that is provided in an oil passage between a bottom-side oil chamber of a boom cylinder and a control valve and is closed when the boom is not lowered, and a controller. The controller releases a closed state of the hydraulic oil holding circuit when the excavator is in a predetermined unstable state, and controls a released state so that an acting velocity in a lowering direction of the boom becomes less than or equal to a predetermined reference.

A system for a grading machine includes a lift cylinder sensor to measure a position or movement of a lift cylinder, which is coupled to a drawbar. The drawbar is coupled to a circle. The circle is coupled a blade carrier assembly, and the blade carrier assembly is coupled to a blade. The system also includes a drawbar sensor to measure a position or movement of the drawbar, a circle sensor to measure a position or movement of the circle, a blade carrier assembly sensor to measure a position or movement of the blade carrier assembly, and a blade sensor to measure a position or movement of the blade. A controller receives information from the lift cylinder sensor and one or more of the aforementioned sensors and determines whether one or more wear components is in need of inspection, repair, or replacement.

A positioner according to the present invention includes: an electro-pneumatic converter that converts an input electric signal into a pneumatic signal and controls the valve opening of a regulating valve by driving an operational unit in accordance with the pneumatic signal; an operating-point searching unit that changes the electric signal by performing open loop control to search for an operating point indicating a target valve-opening value of the regulating valve when an output air pressure of the pneumatic signal starts to change; and a PST executing unit that executes a PST on the regulating valve by using the operating point found by the operating-point searching unit. The operating-point searching unit sets the operating point based on a value of the electric signal when the output air pressure matches a first reference value.

Many operators choose not to utilise partial-stroke testing arrangements even when the equipment required for it to be performed is available, due to a perceived risk of over-travel and/or spurious trip. To alleviate this, we describe a safety valve system comprising a valve operable to move between an operating state and a safe state, a valve actuator operatively connected to the valve to control its state, and including a bias toward the safe state, a pair of drive members powered by a pressure media, each acting against the bias to urge the valve toward the operating state, a first control valve arranged to selectively convey pressure media to both drive members and to withdraw supply on receipt of a safety trigger, and a second control valve arranged to selectively convey pressure media to one drive member only of the pair and to withdraw supply on receipt of a test signal. In this way, a partial stroke test is possible via the second control valve, but the other drive member of the pair will remain active thus acting as a buffer that prevents excessive movement of the valve.

In order to provide an improved method and device to facilitate the teach-in of gripper positions, it is suggested that the positions be automatically detected. The procedure shall include: starting a teach-in process, detecting the position and the direction of movement of the actuating element on its path with a sensor, performing gripping movements from one position to another and stopping the gripper in each of the positions, storing the position of the actuating element when the gripper stops and storing the direction of movement from which this position was approached as the associated direction of movement, stopping the teach-in process when as many different positions with the associated movement directions have been stored as there are gripper positions, assigning of the gripper positions to the three positions from the stored positions and the stored, associated movement directions.