Alps Electric Co., Ltd.

Kisei Hirobe

Yukimitsu Yamada

Katsuyuki Kawarada

Junichi Saito

Katsuyuki Kawarda

An X-axis sensor, a Y-axis sensor, and a Z-axis sensor that detect a geomagnetic vector are provided, and the direction of the geomagnetic vector is sought on a spherical coordinate from the detection output of each sensor. A reference axis is determined in the spherical coordinate, a hypothetical central point is sought on the reference axis depending on data of two coordinate detection points, a perpendicular line to a plane that includes vectors from the hypothetical central point to the respective data is sought from the cross product of the vectors, an axis that is parallel to the perpendicular line and passes through an origin is set to be a calculated rotational axis, and movement centered around the calculated rotational axis is specified.

Geomagnetism sensing device

An azimuth calculation program is a computer-executable program that performs an azimuth calculation using output of a magnetic sensor. The azimuth calculation program includes a first step of generating one triangle in three-dimensional space using three output values of a magnetic sensor unit, a second step of determining a circumcircle of the triangle, and a third step of performing an azimuth calculation using center coordinates of the circumcircle and output values of the magnetic sensor.

Azimuth calculation program and electronic compass

A constant-voltage circuit includes a first reference voltage generation unit which generates a reference voltage using a bandgap voltage of a bipolar transistor, a second reference voltage generation unit which generates a reference voltage using a field effect transistor, a constant voltage generation unit which generates a constant voltage with reference to either an output voltage of the first reference voltage generation unit or an output voltage of the second reference voltage generation unit, and a control unit which controls the first reference voltage generation unit, the second reference voltage generation unit, and the constant voltage generation unit. During an initial activation period, the first reference voltage generation unit and the second reference voltage generation unit are operated, and during a subsequent operation period, the first reference voltage generation unit is stopped.

Constant-voltage circuit

A motion sensing program for executing a motion sensing based on at least a biaxial output of a magnetic sensor, which includes the steps of determining with respect to execution of the motion sensing based on the output of the specific biaxial output of the magnetic sensor upon its rotation in a predetermined direction, and identifying the rotating direction when execution of the motion sensing is determined.

Motion sensing program and electronic compass with motion sensing program

The object of the present invention is to provide a calibration program and an electronic compass that make it possible to calibrate the output of a magnetic sensor with a small amount of computation while a user does not notice the execution of calibration. A calibration program according to an aspect of the invention includes: a step of forming at least two trianglesandwith the use of at least four outputs of a magnetic sensor in a three-dimensional space; a step of finding circlesandcircumscribed about the triangleandrespectively; and a step of finding the intersection of normal vectorsandeach of which passes through the center of the corresponding circumscribed circle so as to find a reference point.

Growing community of inventors

Miyagi-ken, Japan

Kisei Hirobe