Driving assistance device
A driving assistance device configured to assist a driver of a towing vehicle in vehicle operation includes: a captured image acquisition unit configured to acquire a captured image of a periphery of the towing vehicle, the captured image captured by an image capture device of the towing vehicle; an overhead image generation unit configured to, based on the captured image, generate an overhead image from above onto the periphery of the towing vehicle; a point calculation unit configured to calculate, in the overhead image, a position of a connection point for connecting a hitch ball of the towing vehicle with a coupler of a towed vehicle as an object to be towed by the towing vehicle; and an image display unit configured to display, on an image display device in the towing vehicle, the overhead image having an icon superimposed on the position of the connection point as an assistance image for assisting the driver in vehicle operation. In the driving assistance device, the point calculation unit calculates the position of the connection point in the overhead image based on a positional relationship between the image capture device and the hitch ball.
1 . A driving assistance device configured to assist a driver of a towing vehicle in vehicle operation, the driving assistance device comprising:
a captured image acquisition unit configured to acquire a captured image of a periphery of the towing vehicle, the captured image captured by an image capture device of the towing vehicle;
an overhead image generation unit configured to, based on the captured image, generate an overhead image from above onto the periphery of the towing vehicle;
a point calculation unit configured to calculate, in the overhead image, a position of a connection point for connecting a hitch ball of the towing vehicle with a coupler of a towed vehicle as an object to be towed by the towing vehicle; and
an image display unit configured to display, on an image display device in the towing vehicle, the overhead image having an icon superimposed on the position of the connection point as an assistance image for assisting the driver in vehicle operation, wherein
the point calculation unit calculates the position of the connection point in the overhead image based on a positional relationship between the image capture device and the hitch ball,
wherein the overhead image generation unit generates the overhead image by changing a position of a view point with respect to an image as the captured image projected on a ground surface, and
wherein, in order to convert the captured image to the image from a virtual view point, the overhead image generation unit converts each coordinate in a captured image coordinate system set along a plane perpendicular to the optical axis of the image capture device, first to the corresponding coordinate in a ground surface coordinate system set along the ground surface, and then to the corresponding coordinate in an overhead image coordinate system.
2 . The driving assistance device according to claim 1 , further comprising:
a steering angle acquisition unit configured to acquire a current steering angle of the towing vehicle; and
a locus calculation unit configured to calculate a moving locus expected of the connection point based on the current steering angle, wherein
the image display unit superimposes the moving locus expected of the connection point on the overhead image before displaying the overhead image.
3 . The driving assistance device according to claim 1 , wherein
the image display unit displays, on the image display device, the captured image and the overhead image as the assistance images, and
among the captured image and the overhead image, each displayed on the image display device, the image display unit superimposes the icon on at least the overhead image before displaying a corresponding one of the assistance images.