Sight-line end estimation device and driving assist device

1. A sight-line end estimation device comprising:

a sight-line direction detection portion that detects a sight-line direction of a driver of a vehicle;

a target object detection portion that detects a position of a target object existing around the vehicle;

a relative position acquisition portion that acquires relative positional information between the driver and the target object detection portion; and

a sight-line end estimation portion that estimates a sight-line end of the driver by detecting a target object whose position detected by the target object detection portion lies substantially in the driver's sight-line direction detected by the sight-line direction detection portion, factoring in the relative positional information acquired by the relative position acquisition portion, and

an evaluation portion that evaluates a likelihood of the driver's sight line being presently directed in a direction of the target object, wherein

the sight-line end estimation portion estimates the driver's sight-line end based on the target object at which it is highly likely that the driver's sight line is presently directed, using a result of evaluation provided by the evaluation portion,

the evaluation portion evaluates the likelihood of the driver's sight line being presently directed in the direction of the target object based on the target object whose position lies substantially in the driver's sight-line direction detected concurrently with the position of the target object, at a plurality of time points, and

the evaluation portion determines that, of target objects whose positions lie substantially in the driver's sight-line direction acquired concurrently with the positions of the target objects at any one of the plurality of time points, a common target object that is common to the plurality of time points is the target object at which it is highly likely that the driver's sight line is presently directed.

2. The sight-line end estimation device according to claim 1 , wherein the sight-line end estimation portion corrects at least one of the driver's sight-line direction and the position of the target object based on the relative positional information so that the position of the driver and the position of the target object detection portion coincide with each other, and then detects the target object whose position lies substantially in the driver's sight-line direction.

3. The sight-line end estimation device according to claim 1 , wherein the relative position acquisition portion acquires relative positional information between the driver's eye and the target object detection portion.

4. The sight-line end estimation device according to claim 1 , wherein the sight-line direction detection portion detects the driver's sight-line direction at each of the plurality of time points, and the evaluation portion determines an intersecting point of the driver's sight-line directions detected at the plurality of time points, and determines the target object at which it is highly likely that the driver's sight line is presently directed based on a distance between the intersecting point and the target object.

5. The sight-line end estimation device according to claim 1 , wherein the target object detection portion includes a sight field video picture camera that acquires an image of a sight field of the driver, and a millimeter wave radar that emits a millimeter wave and receives a reflected wave of the millimeter wave emitted, and the target object detection portion detects the target object based on the image acquired by the sight field video picture camera and the reflected wave received by the millimeter wave radar.

6. A driving assist device mounted in a vehicle, comprising:

the sight-line end estimation device according to claim 1 ; and

a warning portion that detects an obstacle that is likely to obstruct travel of the vehicle, and outputs a warning if the detected obstacle does not coincide with the target object existing at the sight-line end estimated by the sight-line end estimation device.

7. The sight-line end estimation device according to claim 1 , wherein the target object detection portion includes a sight field video picture camera that acquires an image of a sight field of the driver, and

the relative position acquisition portion acquires the relative positional information between the driver and the sight field video picture camera.