Driver monitoring apparatus

1. A driver monitoring apparatus that monitors a driver of a vehicle, the driver monitoring apparatus including a control circuit that controls monitoring of the driver,

the control circuit comprising:

a state recognition device that recognizes a state of the driver;

a recognition stability determination device that determines a recognition stability of a recognized state output by the state recognition device;

an action request device that makes a request to the driver, the action request device making the request to the driver to perform a first action at a first timing when the recognition stability is not less than a reference value,

wherein, when the recognition stability is less than the predetermined reference value, the action request device makes the request to the driver to perform either

a second action that is different from the first action requested when the recognition stability is not less than the reference value, or

the first action at a second timing that is different from the first timing at which the first action is requested when the recognition stability is not less than the reference value; and

an action detection device that detects an action performed by the driver that responds to the request.

2. The driver monitoring apparatus according to claim 1 , wherein:

the control circuit further includes

a captured image acquisition device that acquires a captured image of a face of the driver, and

a face recognition device that recognizes a component of the face of the driver from the captured image; and

when the recognition stability is less than the reference value and, simultaneously, a predetermined part that is within the component of the face of the driver is not recognized,

the action request device makes the request to the driver to perform a non-image action enabling the action detection device to detect an action of the driver without using image processing.

3. The driver monitoring apparatus according to claim 2 , wherein:

when the predetermined part is recognized, the action request device makes the request to the driver to perform an action at intervals of a reference period; and

when the predetermined part is not recognized, the action request device makes the request to the driver to perform an action at intervals of a period shorter than the reference period.

4. The driver monitoring apparatus according to claim 2 , wherein:

when the predetermined part is recognized, the action request device makes the request to the driver to perform an action to change the predetermined part; and

when the predetermined part is not recognized, the action request device makes the request to the driver to perform an action that is detected by a detector that detects the driver performing the action.

5. The driver monitoring apparatus according to claim 1 , wherein,

the control circuit further includes an attention calling device that calls an attention of the driver either

when the action detection device fails to detect an action of the driver responding to the request, or

when a state of the driver recognized by the state recognition device that is likely to pose a difficulty for driving.

6. The driver monitoring apparatus according to claim 5 , wherein

the control circuit further includes an attention prohibition device that prohibits the attention calling device from calling an attention within a predetermined attention calling interval time after having called the attention.

7. The driver monitoring apparatus according to claim 6 , wherein:

the control circuit further includes an interval time changing device that

shortens the attention calling interval time when the action detection device detects an action of the driver, and

lengthens the attention calling interval time when the attention calling device calls the attention of the driver.