Yazaki Corporation

Takahiro Oikawa

Yoshihito Aoki

Masato Nakajima

Naoto Ishikawa

Kazuyuki Sasaki

Yoshiyuki Suzuki

Hiroyuki Ogura

Masaya Sugita

Tatsumi Ohtsuka

Makoto Takashima

Takahiro Fujishiro

Kouji Ishii

Norio Kitamura

A monitoring method for moving vehicles allows the presence of danger to be determined from the magnitude of an optical flow vector. The optical flow vector is detected as a movement of a single point on an object taken over two images, with one image taken at a preceding time and the other image taken at succeeding time in a series of images. A long and narrow window set in a radial direction from a focus of expansion (FOE) of the earlier image is moved in the same direction on the latter image. An optical flow vector of a target point is defined by a vector connecting the midpoint of a location of a subsequent window and the midpoint of a location at which the long and narrow window is set in the earlier image. The location of the subsequent window is determined by minimizing the sum of absolute values of differences in luminance between the long and narrow window and an area of the latter image overlapping such long and narrow window. The optical flow calculation area is limited to areas in which a difference in luminance between the earlier and latter images exceeds a predetermined threshold, and any influence from scenes outside the road boundaries and from lane-dividing lines or other symbols drawn on the road surface is removed in calculating the optical flow.

Motor vehicle obstacle monitoring system using optical flow processing

Disclosure is a luminous pointer made of a light emission element of the inorganic substance dispersion type, high in accuracy of reading, and low in cost. The light emission element of the inorganic substance dispersion type is shaped as a rod, and includes a linear metal core, an electrically-insulating reflective layer made of an enamel and disposed on the core, a fluorescent light emission layer which is made of an enamel and a fluorescent substance dispersed therein and is disposed on the reflective layer, an electroconductive film disposed on the light emission layer and capable of being electrically connected to the core, and an outer electrically-insulating layer disposed on the film. The film has at least one slit which has a width smaller than the diameter of the luminous pointer and extends as a luminously visible portion in the longitudinal direction of the film. An intermediate electrically-insulating layer made of an enamel may be provided between the light emission layer and the film. The film is manufactured by applying an electroconductive paste or plating with a metal. In the light emission layer, the dispersed fluorescent substance may be provided only near the slit of the film.

Luminous pointer

An angular velocity sensor for detecting angular velocity by converting deflection caused by the coriolis force into an electrical signal. The sensor includes a vibratory member having at least three main surfaces including a first main surface having a driving transducer provided thereon, and second and third surfaces substantially perpendicular to the first main surface respectively, and being parallel to each other, the second and third main surfaces having detecting piezoelectric transducers, respectively. Additionally, support members are connected to the second and third main surfaces to respectively support vibration-steady points of the vibratory member. At least one longitudinal end portion of the vibratory member has a cross-section in such a manner that a length between the second and third main surfaces is shorter than a length of the first main surface. In this manner, the sensitivity of the angular velocity sensor is improved.

Angular velocity sensor

An oscillatory angular speed detecting apparatus is disclosed which includes a pillar-shaped oscillator body and drive and readout piezoelectric transducers attached to first, second, and third surfaces of the oscillator body, the first side surface being perpendicular to the second side surface and the third side surface being parallel to the first side surface, in which vibration of the oscillator body is transduced into a readout signal by the readout transducer. A phase detecting device detects variations of phases of the readout signals, and an amplitude detecting device detects variations of amplitudes of the readout signals, and the angular speed is detected from the phases detected by the phase detecting device and/or the amplitude detected by the amplitude detecting device.

Oscillatory angular speed detecting apparatus

To eliminate the harmful influence of drift when integrating a sensor signal, the sensor signal is integrated from a time point a first predetermined time period before the sensor signal level becomes higher than the perdetermined signal level to a time point a second predetermined time period after the sensor signal level becomes lower than the predetermined signal level.

Sensor signal integrating method

To increase the stability and sensitivity of a vibrational angular velocity sensor, the vibrator is airtightly housed within a glass vacuum casing whose inside surface is coated with a metallic film. Further, conductive lead pins electrically connected between vibrator signal terminals and a printed circuit board for a signal processing circuit and fixing pins mechanically fixed to the printed circuit board are arranged with a constant length outside the casing in parallel to each other. Further, two vibrator support pins are fixed to the glass casing by glass material. To obtain a high vacuum within the glass casing, a subcasing including a getter is connected to the casing through a connecting tube cut off or sealed after evacuation.

Vibrational angular velocity sensor

In a navigation system by which vehicle travel locations are detected by an angular rate sensor and a distance sensor and the detected vehicle travel locations are corrected so as to be displayed along a map road, the display errors are improved by matching a vehicle turn point behind a route judge area to a map branch point; a route judge area is adjusted according to route conditions to an adjacent branch point or detected travel angles or a distance between two adjacent branch points. Further, non-corrected vehicle location data are displayed only within the route judge area to remove unnatural vehicle location display.

Navigation system using angular rate sensor

The headlight moving apparatus comprises a yaw rate sensor, a headlight position sensor, a vehicle speed sensor, a CPU, and a headlight actuator. The CPU calculates an appropriate headlight turning position on the basis of these three sensor signals. Since the yaw rate sensor can directly detect the vehicle turning motion and direction, it is possible to move the headlights right and left more reliably. Therefore, the adjusted headlights can brighten remote forward road surface when the vehicle runs along a curved road.

Headlight moving apparatus for automotive vehicle

To increase the quality factor Q of the vibrational angular rate sensor and therefore the sensitivity of the sensor, stabilize the sensor performance, facilitate wiring work, and minimize the sensor, a square pillar shaped vibrator, four vibrator node support pins and an external vibrator support base are all formed integral with each other from a single constant elasticity material block. Further, at least three and preferably four piezoelectric elements are connected to an external circuit via at least three and preferably four separate thin film conductive layers each extending from each piezoelectric element, on and along each vibrator node support pin, to an external vibrator support base.

Growing community of inventors

Shizuoka, Japan

Takahiro Oikawa