136results about How to "Avoid calibration" patented technology

This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of:detecting the position of at least three reflections on said eye,transforming said positions to spanning a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation,detecting the position of said center of the eye relative to the position of said reflections and transforming this position to said normalized coordinate system,tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system.Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided. Further, it is not necessary to know the position of light sources. This results in a much more flexible and user friendly system.

A baler comprises a baling chamber and a sensor arrangement. The sensor arrangement comprises at least one sensor arranged to provide information about a mechanical property of a bale built in the baling chamber and a control unit receiving signals from the sensor. The control unit is operable to automatically calibrate the signals from the sensor based upon at least one signal from the sensor received in at least one known state of the sensor.

A surrounding area monitoring apparatus for vehicle includes an infrared camera mounted on a vehicle for capturing images of surrounding area around the vehicle, a unit for generating and displaying images based on image data captured by the camera, and a controller for calibrating output of the camera with respect to a relation between pixels, based on image data produced by imaging a surface of a shutter that opens and closes an aperture introducing a light to the camera. The controller estimates whether a temperature of the camera is stable, based on an operation state of the vehicle, and determines a possibility that a driver is looking at the unit, based on a behavior of the vehicle. When the temperature of the camera is estimated stable and the possibility that the driver is looking at the unit is determined to be low, the means for calibrating executes the calibration.

The present invention discloses a calibration method and system for high-intensity field sensors. The objective of the invention is to solve the problem that a standard field method is less likely to generate high field strength in a test area. The system of the invention comprises a transmitting antenna, a field strength meter, a reverberation chamber, a receiving antenna and a signal receiving system; the reverberation chamber comprises a horizontal agitator and a vertical agitator; the signal receiving system is used for measuring the field strength value of the receiving antenna. The method of the invention includes the following steps that: a calibrated field sensor is arranged in the field uniform area of the reverberation chamber, the transmitting antenna radiates electromagnetic waves into the reverberation chamber; the number of the times of the stepping of the horizontal agitator and the vertical agitator in one agitating cycle is set; when stepping occurs each time, the receiving field value of the field sensor and the aperture receiving power of the receiving antenna are measured; the average receiving field strength value of the field sensor and the average receiving field strength value of the receiving antenna in one agitating cycle are obtained; and the average receiving field strength value of the field sensor is compared with the average receiving field strength value of the receiving antenna, so that the field strength correction factor of the field strength sensor can be obtained. With the method and system of the invention adopted, the calibration of field strength sensors of which the field strength amplitude is above 200V / m can be realized.

The invention discloses a comprehensive ramp stopping and sliding control system applicable to an electric forklift. The system comprises control steps as follows: when a speed detection unit detectsthat the speed of the vehicle is zero, a torque evaluation unit calculates the current torque; when the torque is larger than a set threshold, a ramp staying control unit is triggered, and the vehicleis stopped on a ramp by electric brake of a motor; when the electric brake time of the vehicle exceeds ramp stopping time, the system actively switches to a ramp sliding control unit; the torque evaluation unit calculates the current torque, when the torque is smaller than the preset threshold, the vehicle is regarded to be located on the flat ground, the system actively quits the ramp sliding state, the vehicle is stopped on the flat ground, the torque is smaller than the preset threshold, and the normal working mode returns. The system enters the ramp stopping program by brake instead of anexternal trigger signal. A motor controller stops the motor through closed-loop control to automatically adapt to different ramps. Therefore, formulation of different PI tables for different ramps can be avoided. Stability and safety in the ramp sliding process are realized by adding ramp sliding speed setting items and speed closed loop.

The present disclosure provides a computer implemented method for automatic detection of teeth clenching and / or teeth grinding in a dataset representing the level of biting force vs. time of a subject, the method comprising the steps of a) calculating a threshold level of biting force assigned to time t=t1 based on a background level determined from the dataset at a prior time t=t1-Tback, where Tback is a first predefined period of time,b) checking the level of biting,and if the level of biting force at time,t, exceeds the threshold level assigned to time t for a second predefined period of time, Tclench / grind, then assigning an event of teeth clenching to time t,c) if an event of teeth clenching has been assigned to time t, then either waiting a predefined period of time 10 T wait,or waiting until the level of biting is below the threshold for another predefined period of time Tend, d) if no events of teeth clenching and / or teeth grinding have been assigned for a third predefined period of time Tsilence, then repeating steps a)-c),e)if events of teeth clenching and / or teeth grinding have been assigned for a third predefined period of time Tsilence, then repeating only steps b)-c).

The invention relates to a height sensor calibration method, device and equipment, an electric control air suspension and a vehicle, and the method comprises the steps: entering a calibration mode ifa height sensor calibration identification is not obtained; in the calibration mode, in the process of calibrating and adjusting the height of the detected object, acquiring coil charging data of theheight sensor; determining a working mode to which the height sensor belongs according to a preset association relationship between the coil charging data and the working mode of the height sensor; and calibrating the height sensor according to the working mode so as to carry out actual adjustment on the height of the detected object according to the working mode. By the adoption of the technicalscheme, the tedious degree of the installation and calibration process of the height sensor can be reduced, and the installation and calibration efficiency of the height sensor is improved.