33results about How to "Easy and accurate calibration" patented technology

In an autonomously navigating utility vehicle adapted to run a working area defined by a laid boundary wire autonomously having a pair of magnetic sensors installed on either sides of the vehicle at positions laterally symmetrical with respect to a vehicle straight forward center line to produce outputs indicating intensity of magnetic field of the wire, an angular velocity sensor adapted to produce an output indicating angular velocity around a vertical axis of the vehicle, the vehicle is controlled to move to a prescribed position at which an angle of the center line relative to the laid wire becomes a reference angle based on the outputs of the magnetic sensors, and to turn by 180 degrees, and calibrates the output of the angular velocity sensor by outputs of the angular velocity sensor obtained at the turning.

The invention relates to a method and arrangement for measuring a timber piece (4) in a wood handling machine (1). Such a wood handling machine comprises booms (2) arranged in a base machine and a wood handling device (3) operating therein. In such a wood handling machine (1), a wood handling device (3) grips the timber piece (4) to be handled, after which one end of the timber piece is guided into a measuring carriage (5) in the wood handling machine by the wood handling device. The timber piece arranged in the measuring carriage is subjected to one or more observation measures by observation means provided in the measuring carriage.

A calibration apparatus for an image forming apparatus includes a calculation unit for calculating a color deviation by subtracting a target value from each value on the two orthogonal axes not including brightness of a color coordinate system based on a measured color value of a printed material and a display unit for displaying the color deviation with respect to each gray balance at the feedback such that the number of times of inversions of a sign of the color deviation calculated by the calculation unit and a variation width of the color deviation when the sign of the color deviation is inverted can be detected.

A by-pass and pressure regulator valve exhibiting: an inlet mouth and an outlet mouth set in reciprocal communication by a main conduit; a by-pass mouth. The by-pass and pressure regulator valve comprises: an obturator, mobile between at least a closed position, in which it interrupts fluid communication between the main conduit and the by-pass mouth, and at least an open position, in which the fluid communication is not interrupted; operating pressure control means, predisposed to move the obturator from the closed position; means for determining a flow pressure loss in fluids crossing the main conduit, arranged along the main conduit in order to separate a first tract upstream of the main conduit from a second tract downstream thereof; obturator command means governed by a fluid pressure difference between the first tract and the second tract of the main conduit, distinct from the operating pressure control means but operatively connected to the obturator.

A computer (10) measures amplitudes and phases respective received signals S60a relative to a transmitting signal (S22a) when radio waves are radiated solely from each of the scatterer antennas (50-n) and received by using a calibration receiving antenna (60a), determines a target amplitude based on measured amplitudes, and determines a target phase based on measured phases. Reference attenuation amount control voltages (VAa-n) for respective attenuators (14a-n) are set to attenuation amount control voltages for making the measured amplitudes coincidence with an identical target amplitude, and a reference phase shift amount control voltage (VPa-n) for each phase shifter (13a-n) is set to phase shift amount control voltages for making the measured phases coincidence with an identical target phase.

The invention discloses a position calibrating method of a medical ultrasonic three-dimensional imaging based on linear scanning, comprising the steps that a rectangular solid with known sizes is used as a scanning object, on the premise of assuming that an angle conversion relationship does not exist between an original ultrasonic image plane and a linear guide rail, a two-dimensional image is subjected to the three-dimensional reconstruction, and then an actual mathematic relationship of the angle and the deformation amount of the reconstructed rectangular solid between the original ultrasonic image plane and the linear guide rail can be calculated; and in the actual calibrating process, the rectangular solid is scanned by a linear scanning method, the sequence of the ultrasonic image is subjected to the three-dimensional reconstruction, the deformation amount of the reconstructed rectangular solid is substituted into a mathematic relationship to calculate the rotation angle between the original ultrasonic image plane (i.e. the position of an ultrasonic probe) and the linear guide rail, and the rotation angle is the calibrating result of the position of the ultrasonic probe in the linear scanning mode. The position calibrating method has the advantages that the simplicity and the easy understanding are realized, the operability is high, the test is simple, and the calibrating is convenient and accurate. The position calibrating method can be used for a three-dimensional ultrasonic imaging system based on a free arm linear scanning method or a mechanical driving linear scanning method.

The invention relates to a method for detecting the internal vacuum degree of an accelerometer through servo circuit frequency sweeping, which is technologically characterized by comprising the following steps: S1, before vacuum sealing, measuring the frequency sweeping peak amplitude inside an accelerometer through a closed-loop frequency sweeping approach, and calibrating the vacuum degree of the accelerometer; and S2, after vacuum sealing of the accelerometer, measuring the frequency sweeping peak amplitude through the closed-loop frequency sweeping approach, and comparing the vacuum degreewith the previous calibrated value, so as to compete accelerometer vacuum degree test. The vacuum degree is tested through an electrical servo circuit closed-loop frequency sweeping approach, withoutthe need to change the original design of the accelerometer. The servo circuit adopts a pure proportional amplification link, so that frequency sweeping can completely reflect the internal characteristics of acceleration, and the influence of the circuit link on calibration is reduced. The accuracy of vacuum degree measurement is improved by adjusting the gain of a proportional amplifier.