Abstract: A driving assistance device includes: a risk degree obtaining portion obtaining a degree of a risk of an event threatening a safety of a driver when an occurrence of the event is predicted; a risk handling control portion controlling an execution of a risk handling measure by a risk handling unit against the event that is predicted; a risk factor obtaining portion obtaining a factor which causes the risk as a risk factor; and a presentation control portion controlling a presentation of information about the risk factor. The presentation control portion presents information indicating a presence of the risk factor when the risk handling control portion controls the risk handling unit not to execute the risk handling measure and the degree of the risk is equal to or higher than a predetermined value.

Abstract: A driving assistance device includes: a risk degree obtaining portion obtaining a degree of a risk of an event threatening a safety of a driver when an occurrence of the event is predicted; a risk handling control portion controlling an execution of a risk handling measure by a risk handling unit against the event that is predicted; a risk factor obtaining portion obtaining a factor which causes the risk as a risk factor; and a presentation control portion controlling a presentation of information about the risk factor. The presentation control portion presents information indicating a presence of the risk factor when the risk handling control portion controls the risk handling unit not to execute the risk handling measure and the degree of the risk is equal to or higher than a predetermined value.

Abstract: A driving assistance device includes: a risk degree obtaining portion obtaining a degree of a risk of an event threatening a safety of a driver when an occurrence of the event is predicted; a risk handling control portion controlling an execution of a risk handling measure by a risk handling unit against the event that is predicted; a risk factor obtaining portion obtaining a factor which causes the risk as a risk factor; and a presentation control portion controlling a presentation of information about the risk factor. The presentation control portion presents information indicating a presence of the risk factor when the risk handling control portion controls the risk handling unit not to execute the risk handling measure and the degree of the risk is equal to or higher than a predetermined value.

Abstract: A driving assistance device: acquires presentation target information; controls a presentation of the presentation target information; calculates a recognition requisite time which is required for a driver to recognize the presentation target information when the presentation target information is presented; calculates a degree of risk which endangers a safety of the driver; calculates a given driving time according to the degree of risk which endangers the safety of the driver; and calculates a safe driving requisite time, which is a time required for the driver to drive safely, according to the degree of risk which endangers the safety of the driver. In a non-presented state of the presentation target information, when the given driving time becomes longer than a sum of the safe driving requisite time and the recognition requisite time, the driving assistance device presents the presentation target information.

Abstract: A driving assistance device includes: a risk degree obtaining portion obtaining a degree of a risk of an event threatening a safety of a driver when an occurrence of the event is predicted; a risk handling control portion controlling an execution of a risk handling measure by a risk handling unit against the event that is predicted; a risk factor obtaining portion obtaining a factor which causes the risk as a risk factor; and a presentation control portion controlling a presentation of information about the risk factor. The presentation control portion presents information indicating a presence of the risk factor when the risk handling control portion controls the risk handling unit not to execute the risk handling measure and the degree of the risk is equal to or higher than a predetermined value.

Abstract: A driving assistance device: acquires presentation target information; controls a presentation of the presentation target information; calculates a recognition requisite time which is required for a driver to recognize the presentation target information when the presentation target information is presented; calculates a degree of risk which endangers a safety of the driver; calculates a given driving time according to the degree of risk which endangers the safety of the driver; and calculates a safe driving requisite time, which is a time required for the driver to drive safely, according to the degree of risk which endangers the safety of the driver. In a non-presented state of the presentation target information, when the given driving time becomes longer than a sum of the safe driving requisite time and the recognition requisite time, the driving assistance device presents the presentation target information.

Abstract: A sensor detects the presence or the absence of an obstacle by radiating a laser beam to the outside of a casing through a light projecting mirror and by letting the reflected light from an obstacle enter a light receiving element through a light receiving mirror. A light projecting window with a light projecting mirror positioned and a light receiving window with a light receiving mirror are positioned in the casing with a space therebetween to prevent reflected light from directly entering the light projecting window. The mirrors are attached to a rotation shaft of a motor, or rotation shafts of motors, synchronously rotatable provided between both mirrors. The optical axis of light radiated to the outside of the casing is set to face in a higher direction than horizontal to radiate in a cone-shaped form.