Control apparatus of vehicular lamp, vehicular lamp system, and control method for vehicular lamp

A vehicular lamp system comprising:

• a vehicular lamp in which an optical axis is adjustable;
• an acceleration sensor;
• and
• a control apparatus configured to adjust an optical axis position of the vehicular lamp, the control apparatus including:
• a receiving portion configured to receive a detection value of the acceleration sensor;
• a reference information retaining portion configured to retain reference information indicative of a positional relationship of an axis of the acceleration sensor in a state in which the acceleration sensor is mounted to a vehicle, an axis of the vehicle (300) that determines a posture of the vehicle, and a road surface that the vehicle is on, wherein the reference information is obtained in a predetermined initialization process;
• a correction ratio generating portion configured to, after the initialization process, calculate an acceleration ratio that is a ratio of an amount of change in acceleration in a vehicle longitudinal direction of the vehicle while traveling to an amount of change in acceleration in a vehicle vertical direction of the vehicle while traveling, and to derive a correction ratio for correcting a positional relationship of the road surface and at least one of the axis of the acceleration sensor and the axis of the vehicle in the reference information, using the obtained acceleration ratio;
• and
• a control portion configured to, after the correction ratio is derived, output an adjustment signal instructing that an optical axis position of the vehicular lamp be adjusted, using the acceleration ratio, the reference information, and the correction ratio.

A control method for a vehicular lamp, comprising:

• retaining reference information indicative of a positional relationship of an axis of an acceleration sensor in a state in which the acceleration sensor is mounted to a vehicle an axis of the vehicle that determines a posture of the vehicle, and a road surface that the vehicle is on, wherein the reference information is obtained in a predetermined initialization process;
• calculating, after the initialization process, an acceleration ratio that is a ratio of an amount of change in acceleration in a vehicle longitudinal direction of the vehicle while traveling to an amount of change in acceleration in a vehicle vertical direction of the vehicle while traveling;
• deriving a correction ratio for correcting a positional relationship of the road surface and at least one of the axis of the acceleration sensor and the axis of the vehicle in the reference information, using the obtained acceleration ratio;
• and
• outputting, after the correction ratio is derived, an adjustment signal instructing that an optical axis position of the vehicular lamp be adjusted, using the acceleration ratio, the reference information, and the correction ratio.