Fuji Electric Co., Ltd.

Taichi Tanigawa

Hideyuki Tanaka

Hideo Shimizu

Yasukazu Sano

Takehide Hirabayashi

Akio Izumi

Seiki Igarashi

Akihiko Okabe

Takayuki Usuda

An electric power conversion apparatus includes a noise reduction device for reducing the common mode noise and the normal mode noise caused by on/off of the switching devices of an electric power conversion apparatus for driving an AC motor. Since the noise-compensation-current supply circuit of the noise reduction device uses devices with a lower breakdown voltage, the operating speed of the noise-compensation-current supply circuit is higher than the operating speed of the conventional noise-compensation-current supply circuit which uses devices with a higher breakdown voltage equivalent to the DC voltage of the electric power conversion apparatus.

Electric power conversion apparatus with noise reduction device

An apparatus for determining an occupant's posture is provided which includes a sensor having at least one pair of linear photosensor arrays each comprising a plurality of photosensor elements, for forming an image of an occupant, a distance measurement processor that derives distance distributions in fields of view monitored by the linear photosensor arrays, from the image of the occupant formed by the sensor, and an occupant discrimination processor that compares patterns of the distance distributions with model patterns of distance distributions preliminarily stored in the processor, so as to determine the presence and posture of the occupant. The linear fields of view are set to extend in a substantially horizontal direction with respect to the occupant, and the occupant discrimination processor first examines at least one of symmetry of the distance distribution pattern in each field of view, concave or convex shape of the pattern, degree of similarity in variations in the distance distribution patterns between adjacent fields of view, and a distribution of distances measured at a particular position of the fields of view, and then determines the posture of the occupant by comparing the patterns of the distance distributions actually measured, with a group of model patterns that is selected in advance depending upon the result of the examination.

Apparatus for detecting occupant's posture

The present invention detects not only the presence of an occupant, but also his/her posture based on the distance distribution of each portion of the occupant within each of monitor fields of view, which distance distribution is obtained by means of a single-stage or multistage occupant sensor. The result of the detection can be used in controlling inflation of an air bag, so as to avoid an accident that might otherwise occur upon inflation of the air bag, thus assuring increased safety and reliability. Since the acceleration can be calculated by arithmetic processing of the output of the distance sensor, there is no particular need to provide an exclusive acceleration sensor. Further, an optical system including the distance sensor may be designed so that the sensor can also detect an occupant whose part of the body is thrust out of automobile.

Control method for inflating air bag for an automobile

A method of the invention corrects a detection error, caused by an assembly error, in a distance or a distance-related index detected from an image captured in the visual field of an image detection module including an optical device and a pair of image sensing devices, each including a plurality of image sensors. In the method, the visual field is divided into windows disposed in a two-dimensional matrix format in order to detect the distance or a parallax for a pair of images in each window; the characteristics of an error is expressed in a detected value caused by an angle error in the assembly of the image detection module, as a quadratic polynomial for two angle variables indicating the position of the window within the visual field; parallax for a plurality of windows is detected after a test sample image has been provided to the module; the coefficient value for each term in the polynomial is determined based on the results of the detection, and these values are stored in a storage device; and, when using the image detection module to detect actual distances, the detected value for each window is corrected by adding to it the value of the polynomial to which the stored values of the coefficients and the values of the variables indicating the position of the window are applied.

Method for correcting detected distance values

An inter-vehicle distance to a preceding or following vehicle is reliably determined by using a simple processing, to alert the following vehicle to approach a dangerous range. The distance measurement apparatus includes a pair of light-receiving devices disposed on image-forming surfaces of lenses and having sensor lines and measurement windows on each sensor line at a certain interval, a distance detection device, a white line detection device and a vehicle detection device. The distance detection device detects distances at points, the coordinates of which are specified by the sensor line numbers and measurement window addresses. By using the detection results, the white line detection device detects a sensor line in which a white line on a road surface is present. By using the detection results obtained from the distance detection device relating to the sensor lines in which the white line is not present, the vehicle detection device checks a presence of a vehicle and outputs information on the inter-vehicle distance and the direction of the vehicle. The following vehicle may be alerted by flashing the brake lights.

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Tokyo, Japan

Taichi Tanigawa