US-20260124985-A1 - ROAD SURFACE DRAWING APPARATUS FOR VEHICLE

US20260124985A1US 20260124985 A1US20260124985 A1US 20260124985A1US-20260124985-A1

Abstract

A road surface drawing apparatus for a vehicle includes a road surface drawing lamp that irradiates a patterned light and a controller that controls the road surface drawing lamp. The controller determines a plurality of conditions including a first condition, a second condition, and a third condition each time the vehicle travels a fixed distance. The first condition is that the outside temperature of the vehicle is equal to or lower than a predetermined temperature. The second condition is that a brightness of light reflected from an area illuminated by a headlight of the vehicle is equal to or lower than a predetermined brightness. The third condition is that at least one of ABS, ESC, and TRC has been activated during the most recent predetermined distance traveled by the vehicle. The controller performs a glare reduction control of the patterned light when the plurality of conditions is satisfied.

Inventors

Masaya Watanabe
Katsutoshi Tsuzuki
Masakazu DEAI
Akinori Sakai
Kento NAKAZATO

Assignees

TOYOTA JIDOSHA KABUSHIKI KAISHA

Dates

Publication Date: 20260507
Application Date: 20251003
Priority Date: 20241105

Claims (8)

1 . A road surface drawing apparatus for a vehicle, comprising: a road surface drawing lamp that irradiates a patterned light toward a road surface; and a controller that controls the road surface drawing lamp, wherein the controller determines a plurality of conditions including a first condition, a second condition, and a third condition each time the vehicle travels a fixed distance, the first condition is that an outside temperature of the vehicle is equal to or lower than a predetermined temperature at which the road surface may freeze, the second condition is that a brightness of light reflected toward the vehicle from an area illuminated by a headlight of the vehicle is equal to or lower than a predetermined brightness, the third condition is that at least one of an anti-lock brake control, which suppresses wheels of the vehicle from locking, a skid suppress control, which suppresses the vehicle from skidding, and a traction control, which suppresses wheels of the vehicle from spinning, has been activated during the most recent predetermined distance traveled by the vehicle, and the controller performs a glare reduction control that stops irradiation of at least a part of the patterned light, reduces the amount of light of at least a part of the patterned light, or changes a pattern of at least a part of the patterned light when the plurality of conditions is satisfied.
2 . The road surface drawing apparatus for vehicle according to claim 1 , wherein the controller determines the plurality of conditions each time the vehicle travels the fixed distance during which the glare reduction control is performed, and terminates the glare reduction control when at least one of the first condition, the second condition, and the third condition is no longer satisfied.
3 . The road surface drawing apparatus for vehicle according to claim 1 , wherein the patterned light includes a distal pattern element that is irradiated onto the road surface furthest from the vehicle when the glare reduction control is not performed, and the controller stops irradiation of at least the distal pattern element of the patterned light in the glare reduction control.
4 . The road surface drawing apparatus for vehicle according to claim 2 , wherein the patterned light includes a distal pattern element that is irradiated onto the road surface furthest from the vehicle when the glare reduction control is not performed, and the controller stops irradiation of at least the distal pattern element of the patterned light in the glare reduction control.
5 . The road surface drawing apparatus for vehicle according to claim 1 , wherein the patterned light includes a distal pattern element that is irradiated onto the road surface furthest from the vehicle, and the controller reduces the amount of light of at least the distal pattern element of the patterned light in the glare reduction control compared to when the glare reduction control is not performed.
6 . The road surface drawing apparatus for vehicle according to claim 2 , wherein the patterned light includes a distal pattern element that is irradiated onto the road surface furthest from the vehicle, and the controller reduces the amount of light of at least the distal pattern element of the patterned light in the glare reduction control compared to when the glare reduction control is not performed.
7 . The road surface drawing apparatus for vehicle according to claim 1 , wherein the patterned light includes a distal pattern element that is irradiated onto the road surface furthest from the vehicle, and the controller, in the glare reduction control, changes a shape of the distal pattern element of the patterned light such that a tip of the distal pattern element of the patterned light on the road surface is closer to the vehicle than when the glare reduction control is not performed.
8 . The road surface drawing apparatus for vehicle according to claim 2 , wherein the patterned light includes a distal pattern element that is irradiated onto the road surface furthest from the vehicle, and the controller, in the glare reduction control, changes a shape of the distal pattern element of the patterned light such that a tip of the distal pattern element of the patterned light on the road surface is closer to the vehicle than when the glare reduction control is not performed.

Description

CROSS REFERENCE TO RELATED APPLICATION This application claims priority to Japanese Patent Application No. 2024-193471 filed on Nov. 5, 2024, which is incorporated herein by reference in its entirety including the specification, claims, drawings, and abstract. TECHNICAL FIELD This specification discloses a road surface drawing apparatus for a vehicle that draws images on a road surface surrounding the vehicle. BACKGROUND It has been proposed to equip a vehicle with a road surface drawing apparatus. The road surface drawing apparatus draws images on a road surface around the vehicle. The road surface drawing apparatus, for example, irradiates a patterned light in conjunction with a turn signal lamp to draw images of predetermined shapes on the road surface. Patent Literature 1 (JP 2019-51792 A) discloses a road surface drawing apparatus that irradiates a patterned light from a vehicle onto a road surface. This road surface drawing apparatus detects a road surface image drawn on the road surface by the irradiated patterned light, and when the detected road surface image is missing or distorted, changes the position or range on the road surface where the patterned light is irradiated. SUMMARY During the winter season, a frozen road surface such as mirror-smooth ice or black ice (hereinafter referred to as “mirror-smooth ice, etc.”) may appear. On the frozen road surface such as mirror-smooth ice, etc., an incident light is easily reflected like a mirror. Therefore, there is a risk that the patterned light from the road surface drawing apparatus may be reflected like a mirror on mirror-smooth ice, etc., and the reflected light may cause glare to pedestrians, etc. This specification discloses a road surface drawing apparatus for a vehicle that can suppress glare caused by a patterned light from the road surface drawing apparatus being reflected off a frozen road surface and causing discomfort to people outside the vehicle. A road surface drawing apparatus for a vehicle disclosed in this specification includes a road surface drawing lamp that irradiates a patterned light toward a road surface; and a controller that controls the road surface drawing lamp. The controller determines a plurality of conditions including a first condition, a second condition, and a third condition each time the vehicle travels a fixed distance. The first condition is that an outside temperature of the vehicle is equal to or lower than a predetermined temperature at which the road surface may freeze. The second condition is that a brightness of light reflected toward the vehicle from an area illuminated by a headlight of the vehicle is equal to or lower than a predetermined brightness. The third condition is that at least one of an anti-lock brake control (ABS), which suppresses wheels of the vehicle from locking, a skid suppress control (ESC), which suppresses the vehicle from skidding, and a traction control (TRC), which suppresses wheels of the vehicle from spinning, has been activated during the most recent predetermined distance traveled by the vehicle. The controller performs a glare reduction control that stops irradiation of at least a part of the patterned light, reduces the amount of light of at least a part of the patterned light, or changes a pattern of at least a part of the patterned light when the plurality of conditions is satisfied. According to this configuration, it is possible to detect a frozen road surface where specular reflection of the patterned light is likely to occur by using the first condition, the second condition, and the third condition. Note that the second condition is used to determine the nature of the road surface based on the brightness of the reflected light in the area illuminated by the headlights (referred to as the headlight illumination area). Specifically, when the brightness of the reflected light in the headlight illumination area is high, the road surface is determined to be a snow-covered road or similar surface where diffuse reflection is likely to occur (and specular reflection is unlikely to occur). On the other hand, when the brightness of the reflected light in the headlight illumination area is low, the road surface is determined to be a mirror-smooth ice, etc. where diffuse reflection is unlikely to occur (and specular reflection is likely to occur). According to the above configuration, when a frozen road surface such as a mirror-smooth ice, etc. which is prone to specular reflection of light, is detected using the first condition, the second condition, and the third condition, the glare reduction control such as stopping the irradiation of the patterned light is performed, thereby suppressing glare to people outside the vehicle caused by the patterned light being reflected from the frozen road surface. In the road surface drawing apparatus for vehicle according to the present disclosure, the controller may determine the plurality of conditions each time the vehicle travels the f