Control device and electric vehicle

1. A control device configured to perform a collision preventing control between an obstacle and an electric vehicle based on an output of an obstacle detection unit which is configured to detect the obstacle within a predetermined range in a traveling direction of the electric vehicle, the control device comprising:

a risk level determination unit configured to determine a collision risk level between the obstacle and the electric vehicle based on a distance between the obstacle and the electric vehicle; and

a control level adjustment unit configured to adjust a control level of the collision preventing control based on the collision risk level and perform the collision preventing control with the adjusted control level,

wherein the control level adjustment unit lowers the control level and causes the electric vehicle to display presence of the obstacle when a releasing unit configured to temporarily release the collision preventing control is operated by a driver during the collision preventing control.

2. The control device according to claim 1 ,

wherein the risk level determination unit determines the collision risk level based on the distance between the obstacle and the electric vehicle and an expected path of the electric vehicle, and

wherein when the releasing unit is operated, the control level adjusting unit resumes the collision preventing control on a condition that the collision risk level is lowered.

3. The control device according to claim 1 , wherein the collision risk level decreases as the distance between the obstacle and the electric vehicle increases.

4. The control device according to claim 1 , wherein the risk level determination unit determines the collision risk level based on a determination region to which the obstacle belongs among a plurality of determination regions preliminarily determined in accordance with a distance from the electric vehicle within a detection range of the obstacle detection unit.

5. The control device according to claim 4 , wherein the plurality of determination regions change in accordance with a steering angle of the electric vehicle.

6. The control device according to claim 1 ,

wherein the control level increases as the collision risk level increases, and

wherein the control level includes:

a warning displayed state in which a warning is displayed on a display unit;

an alarm notified state in which an alarm sound is issued in addition to displaying the warning;

a deceleration recommended state in which deceleration of the electric vehicle is performed in addition to displaying the warning and issuing the alarm sound; and

a stop recommended state in which the electric vehicle is stopped instead of decelerated in the deceleration recommended state.

7. The control device according to claim 6 , wherein if the control level is in the alarm notified state or the deceleration recommended state when the releasing unit is operated, the control level adjustment unit immediately sets the control level to the warning displayed state, and if the control level is in the stop recommended state when the releasing unit is operated, the control level is set to the warning displayed state on the condition that the electric vehicle is stopped.

8. An electric vehicle comprising:

an obstacle detection unit configured to detect an obstacle within a predetermined range in a traveling direction of the electric vehicle;

a display unit configured to display presence of the obstacle;

a control device configured to perform a collision preventing control between the obstacle and the electric vehicle based on an output of the obstacle detection unit; and

a releasing unit configured to temporarily release the collision preventing control,

wherein the control device includes:

a risk level determination unit configured to determine a collision risk level between the obstacle and the electric vehicle based on a distance between the obstacle and the electric vehicle; and

a control level adjustment unit configured to adjust a control level of the collision preventing control based on the collision risk level and perform the collision preventing control with the adjusted control level, and

wherein the control level adjustment unit lowers the control level and causes the display unit to display the presence of the obstacle when the releasing unit is operated by a driver during the collision preventing control.