Disclosed are a method and a device for detecting a position of a piston rod, a hydraulic cylinder and a working machine. The method includes: acquiring a target image at a target position; obtaining a pixel information corresponding to the target image; comparing the pixel information with a pixel database of the piston rod, a full-stroke pixel information of the piston rod and a relationship between the full-stroke pixel information of the piston rod and a displacement of the piston rod are stored in the pixel database of the piston rod, and the full-stroke pixel information at least comprises the pixel information within a range in which the piston rod is configured to move relative to the target position; and determining a position information of the piston rod based on a comparison result.

A position sensor unit comprising a sensor housing, an optical time-of-flight sensor, and an electronic control unit is presented. The sensor housing includes an optical port such that an optically transmissive seal engaged within the optical port is operable to pass an optical pulse from within the sensor housing to be transmitted to a diaphragm within a pneumatic actuator wellhead and valve assembly, and also, pass a reflected optical pulse from the diaphragm back into the sensor housing. The optical time-of-flight sensor is operable to measure a round-trip propagation time of one or more optical pulses transmitted by the optical-time-of-flight sensor to the diaphragm and reflected back from the diaphragm in order to determine the displacement of the diaphragm. The electronic control unit controls the optical-time-of-flight sensor and provides detected measurements to an external monitoring device.

A pressure vessel arrangement includes a pressure vessel and an optical sensor arrangement. The pressure vessel includes: a cylinder construction having a cylinder wall extending from a cylinder wall first end to a cylinder wall second end, and having an internal surface forming an interior region; a first end cap closing the cylinder wall first end and having an optical window located therein to permit passage of light therethough and into the interior region; a second end cap closing the cylinder wall second end; and a piston constructed to slide within the cylinder construction interior region along a direction between the cylinder all first end and the cylinder wall second end and along the cylinder construction internal surface to separate the interior region into a first end interior region and a second end interior region. The pressure vessel is constructed to withstand a fatigue test of one million cycles at 5,000 psi without failure. The optical sensor arrangement is located outside of the optical window and includes an emitter for emitting light through the optical window and into the interior region and receiving for receiving light reflected from the piston. Also included is a method for providing a piston position feedback in a pressure vessel.

A method is provided for detecting a reciprocal position between a cylinder and a piston of a piston-cylinder unit of a vehicle. The method includes measuring, by means of an optical sensor, a value of an indicative parameter of a color of a reference mark positioned on a portion of the piston. The method also includes comparing the measured value with at least a predetermined threshold value thereof different to a minimum detected threshold of the indicative parameter by the optical sensor; and emitting an alarm signal perceptible by a driver of a vehicle if the measured value is comprised between the threshold value and the minimum value.

The present invention relates to using a self calibrating and recalibrating 230, 925 optical sensors piston rod displacement. Self calibration enables field calibration of uncalibrated 230, 925 optical sensors. During operation, recalibration enables detecting and correcting for wear and damage of the 200 piston rod and/or 230, 925 optical sensors. 210 Calibration positions on the surface of the 200 piston rod are imaged by 230 optical sensors using laser or darkfield lenses designed for optical computer mice. Natural surface patterns can be used in locations where 210 calibration positions are required, which reduces or eliminates the need for marked 210 calibration positions. Marked 210 calibration positions are spatially unique encoded sequences used to determine the piston rod absolute position. Storing only the significant features of 210 calibration positions saves significant memory. The reduced memory requirements of each 210 calibration position enables the use of closely spaced or continuous 210 calibration positions. Multiple 210 calibration position features and multiple 230, 925 optical sensors together collectively provide immunity to localized 208 surface damage. Proximity sensors, 925 time of flight sensors and 031 cumulative relative displacement are used to estimate the 200 piston rod absolute displacement and reduce the number of spatially unique 210 calibration positions needed to compare in order to determine the piston rod absolute displacement.

A method of controlling wash equipment in an automated vehicle wash system having a conveyor includes, measuring one or more contours of a vehicle as the vehicle moves thorough an entry area of the automated vehicle wash system on the conveyor; tracking the distance a fixed point relative to the conveyor moves; associating the one or more contours of the vehicle with the position of the fixed point; determining, based on the one or more contours of the vehicle and the position of the fixed point, commands for operating the wash equipment; delivering the commands to the wash equipment; and operating the wash equipment in accordance with the commands.

A laser piston position sensor for determining the position of a piston within an accumulator, the laser piston position sensor configured to attach to an end of the accumulator, and the accumulator having an aperture in the end thereof exposing the piston within the accumulator to the laser piston position sensor. The laser piston position sensor including a sensor housing enclosing a cavity containing a low pressure gas, and defining an opening from the cavity toward the accumulator, a laser sensor positioned within the cavity for emitting a laser toward the piston of the accumulator via the opening in the sensor housing and the aperture in the accumulator, and a transparent lens positioned between the laser sensor and the accumulator to allow passage of the laser from the laser sensor to the piston, and to separate gases in the accumulator from gases in the cavity of the sensor housing.

A method of controlling wash equipment in an automated vehicle wash system having a conveyor includes, measuring one or more contours of a vehicle as the vehicle moves thorough an entry area of the automated vehicle wash system on the conveyor; tracking the distance a fixed point relative to the conveyor moves; associating the one or more contours of the vehicle with the position of the fixed point; determining, based on the one or more contours of the vehicle and the position of the fixed point, commands for operating the wash equipment; delivering the commands to the wash equipment; and operating the wash equipment in accordance with the commands.

A valve system for a fluid line system in an aircraft engine, which fluid line system has at least one fluid line wherein the at least one fluid line has at least one check valve, wherein the valve position of an actuator in the at least one check valve is changeable, in particular automatically changeable, in dependence on the pressure ratios in each case acting on the at least one check valve. The valve system has a monitoring means for recording the respective valve position, in particular the open position and/or the closed position of the actuator, in dependence on at least one measurement value, wherein a signal is output in dependence on the recorded valve position. The valve system furthermore has a means for setting a minimum required sealing-air stream. The invention also relates to a valve control method.

A sensor (S) is provided for determining the stroke of the piston rod (6) of a fluid cylinder, particularly a hydraulic or pneumatic cylinder. The sensor includes a lighting unit for illuminating a code applied on the surface of the piston rod and differing from said surface by color, a first camera unit with a first lens system for recording a first image of the illuminated code in a first scanning window, an evaluation unit for evaluating output signals of the first camera unit, and an interface for issuing the evaluated output signals as information regarding the position of the piston rod. Additionally, a second redundant camera unit is provided with a second lens system, which serves for recording a second image of the illuminated code in a second scanning window. According to the invention the second camera unit is arranged such that the second scanning window is spaced apart in the direction of the extension of the piston rod by a predetermined value from the first scanning window of the first camera unit. The output signals of the second camera unit are evaluated in an evaluation unit as information about the respective position by forming a difference, with in case of said difference being consistent with a predetermined value the output signal being considered information about the stroke of the piston rod, and in case of inconsistency of the difference with the predetermined value an error message being issued.