Drive assist device and drive assist method

1. A drive assist device of a vehicle, comprising:

one or more sensors associated with the vehicle;

a fatigue degree estimator configured to estimate a fatigue degree of a driver of the vehicle based on information detected by the one or more sensors;

an environmental information acquirer configured to acquire an environmental information around the vehicle based on information detected by the one or more sensors;

a display controller configured to change a display range of an optical flow to be presented to the driver via a display of the vehicle, on a basis of the environmental information or the fatigue degree,

wherein in a case where there is no need to secure a view of the driver in accordance with the environmental information and the driver is not in a fatigue state associated with the fatigue degree, the display controller makes a movement speed of the optical flow faster without changing the display range of the optical flow.

2. The drive assist device according to claim 1 , wherein in a case where the driver is in the fatigue state, the display controller expands a non-display range of the optical flow.

3. The drive assist device according to claim 1 , wherein the fatigue degree estimator estimates the fatigue degree based on the information detected by the one or more sensors on a basis of a heartbeat of the driver, an image information obtained by imaging the driver, a steering angle acceleration when the driver operates a steering wheel, an information of another vehicle around the vehicle, a road information of a road on which the vehicle travels, or a driving duration of the driver.

4. The drive assist device according to claim 1 , wherein in the case it is necessary to secure the view of the driver in accordance with the environmental information, the display controller expands a non-display range of the optical flow in accordance with the environmental information.

5. The drive assist device according to claim 4 , wherein the environmental information is the information regarding a number of other vehicles around the vehicle, the information regarding a curvature of a road along which the vehicle turns, or the information regarding a width of a road on which the vehicle travels.

6. The drive assist device according to claim 1 , wherein the optical flow is displayed on a front windshield in front of the driver.

7. The drive assist device according to claim 1 , wherein the optical flow comprises at least a line or a point, and is projected.

8. The drive assist device according to claim 1 , further comprising

the one or more sensors comprising a vehicle speed acquirer configured to acquire a vehicle speed,

wherein the display controller changes the display range in a case where the vehicle speed falls outside a predetermined range.

9. The drive assist device according to claim 8 , wherein in a case where the vehicle speed deviates from the predetermined range determined in advance, the display controller changes the display range of the optical flow and changes the movement speed of the optical flow, regardless of the fatigue degree.

10. The drive assist device according to claim 9 , wherein in a case where the vehicle speed exceeds the predetermined range and deviates from the predetermined range, the display controller expands a non-display range of the optical flow and makes the movement speed faster.

11. The drive assist device according to claim 9 , wherein in a case where the vehicle speed is below the predetermined range and deviates from the predetermined range, the display controller shrinks a non-display range of the optical flow and makes the movement speed slower.

12. The drive assist device according to claim 9 , wherein in a case where the vehicle speed has entered the predetermined range determined in advance after passage of a certain period of time after change of a display state of the optical flow, the display controller returns the display state of the optical flow to a state before the change.

13. The drive assist device according to claim 9 , wherein in a case where the vehicle speed does not enter the predetermined range determined in advance even when a certain period of time passes after change of a display state of the optical flow, an alert is issued.

14. A drive assist device of a vehicle comprising:

a vehicle speed acquirer configured to acquire a vehicle speed;

a fatigue degree estimator configured to estimate a fatigue degree of a driver of the vehicle based on information detected by one or more sensors associated with the vehicle;

a display controller configured to change a movement speed or a display range of an optical flow to be presented to the driver via a display of the vehicle, in a case where the vehicle speed falls outside a predetermined range; and

an environmental information acquirer configured to acquire an environmental information around the vehicle based on information detected by the one or more sensors,

wherein the display controller changes the display range of the optical flow to be presented to the driver on a basis of the environmental information or a fatigue degree, and

wherein in a case where there is no need to secure a view of the driver in accordance with the environmental information and the driver is not in a fatigue state associated with the fatigue degree, the display controller makes the movement speed of the optical flow faster without changing the display range of the optical flow.

15. A drive assist method comprising:

estimating, by a fatigue degree estimator of a vehicle, a fatigue degree of a driver of the vehicle based on information detected by one or more sensors associate with the vehicle;

acquiring, by an environmental information acquirer of the vehicle, an environmental information around the vehicle based on information detected by the one or more sensors;

changing, by a display controller of the vehicle, a display range of an optical flow to be presented to the driver via a display of the vehicle, on a basis of the environmental information or the fatigue degree,

wherein in a case where there is no need to secure a view of the driver in accordance with the environmental information and the driver is not in a fatigue state associated with the fatigue degree, making, by the display controller, a movement speed of the optical flow faster without changing the display range of the optical flow.

16. A drive assist method comprising:

acquiring, by a vehicle speed acquirer associated with a vehicle, a vehicle speed;

estimating, by a fatigue degree estimator of the vehicle, a fatigue degree of a driver of the vehicle based on information detected by one or more sensors associate with the vehicle;

changing, by a display controller of the vehicle, a movement speed or a display range of an optical flow to be presented to a driver via a display of the vehicle, in a case where the vehicle speed falls outside a predetermined range;

acquiring, by the one or more sensors, an environmental information around the vehicle,

wherein changing, by the display controller, the display range of the optical flow to be presented to the driver comprises changing the display range of the optical flow on a basis of the environmental information or the fatigue degree; and

wherein in a case where there is no need to secure a view of the driver in accordance with the environmental information and the driver is not in a fatigue state associated with the fatigue degree, making, by the display controller, the movement speed of the optical flow faster without changing the display range of the optical flow.

17. A drive assist device comprising circuitry configured to

estimate, by a fatigue degree estimator of a vehicle, a fatigue degree of a driver of the vehicle based on information detected by one or more sensors associate with the vehicle,

acquire, by an environmental information acquirer of the vehicle, an environmental information around the vehicle based on information detected by the one or more sensors; and

change, by a display controller of the vehicle, a display range of an optical flow to be presented to the driver via a display of the vehicle, on a basis of the environmental information or the fatigue degree,

wherein in a case where there is no need to secure a view of the driver in accordance with the environmental information and the driver is not in a fatigue state associated with the fatigue degree, the circuitry makes a movement speed of the optical flow faster without changing the display range of the optical flow.

18. A drive assist device comprising:

circuitry configured to

acquire, by a vehicle speed acquirer associated with a vehicle, a vehicle speed;

estimating, by a fatigue degree estimator of the vehicle, a fatigue degree of a driver of the vehicle based on information detected by one or more sensors associate with the vehicle;

change, by a display controller of the vehicle, a movement speed or a display range of an optical flow to be presented to a driver via a display of the vehicle, in a case where the vehicle speed falls outside a predetermined range; and

acquire, by the one or more sensors, an environmental information around the vehicle, wherein the circuitry changes the display range of the optical flow to be presented to the driver on a basis of the environmental information or a fatigue degree, and

wherein in a case where there is no need to secure a view of the driver in accordance with the environmental information and the driver is not in a fatigue state associated with the fatigue degree, the circuitry makes the movement speed of the optical flow faster without changing the display range of the optical flow.