Vehicle navigation apparatus with route modification by setting detour point

Claim 2

A vehicle navigation apparatus for providing guidance for a vehicle through a detour off of a set route, said apparatus comprising: data storage means for storing map data; route setting means for setting a route from a present vehicle position to a destination as a connected array of intersections; input means for designating a detour point off of the set route; search area setting means for setting a detour search area including the detour point and a Plurality of intersections in said array of intersections and wherein said plurality of intersections is less than said array of intersections; detour searching means for searching said map data to identify a plurality of detour routes, each detour route departing from said set route, passing through the designated detour point and returning to the set route at a respective one of said plurality of intersections of said array within said set detour search area; route selecting means for selecting one of said plurality of detour routes as a selected detour route for which guidance is to be provided; and route guiding means for providing guidance along the set route, as modified by the selected detour route.

Claim 3

A vehicle navigation apparatus in accordance with claim 1 wherein said route selecting means selects the shortest of said plurality of detour routes.

Claim 4

A vehicle navigation apparatus in accordance with claim 2 further comprising present position detecting means for detecting a present position of the vehicle and wherein said detour searching means determines if the detected present position is within said detour search area and if the vehicle is determined to be within said detour search area, identifies as said plurality of detour routes only routes returning to said set route at intersections located ahead of the present position.

Claim 5

A vehicle navigation apparatus in accordance with claim 1 further comprising present position detecting means for detecting a present position of the vehicle and wherein said detour searching means determines if the detected present position is within said detour search area and if the vehicle is determined to be within said detour search area, identifies as said plurality of detour routes only routes returning to said set route at intersections located ahead of the present position.

Claim 6

A vehicle navigation apparatus as claimed in claim 1 wherein the search area setting means sets a rectangular detour search area.

Claim 7

A vehicle navigation apparatus as claimed in claim 5 wherein the rectangular detour search area is set by two points defining apexes of a diagonal of the rectangular detour search area.

Claim 8

A vehicle navigation apparatus for providing guidance for a vehicle through a detour off of a set route, said apparatus comprising: data storage means for storing map data; route setting means for setting a route from a present vehicle position to a destination as a connected array of intersections including intersections Ca, Cb and Cp, input means for designating a detour point; search area setting means for setting a detour search area; said search area setting means calculating a circle of radius f(r), said circle being centered on the designated detour point and cutting the set route at two points and r being the distance between the designated detour point and the closest intersection Cp thereto, identifying intersections Ca and Cb as intersections closest, respectively, to said two points and setting, as the detour search area, an area between the intersections Ca and Cb; detour searching means for searching said map data to identify a plurality of detour routes, each detour route departing from said set route, passing through the designated detour point and returning to the set route at a respective one of a plurality of said intersections of said array within said set detour search area; route selecting means for selecting one of said plurality of detour routes as a selected detour route for which guidance is to be provided; and route guiding means for providing guidance along the set route, as modified by the selected detour route.

Claim 9

A vehicle navigation apparatus for providing guidance for a vehicle through a detour off of a set route, said apparatus comprising: data storage means for storing map data; route setting means for setting a route from a present vehicle position to a destination as a connected array of intersections including intersections Ca, Cb and Cp, input means for designating a detour point; search area setting means for setting a detour search area; said search area setting means calculating a circle of radius f(r), said circle being centered on the designated detour point and cutting the set route at two points and r being the distance between the designated detour point and the closest intersection Cp thereto, identifying intersections Ca and Cb as intersections closest, respectively, to said two points and setting, as the detour search area, an area between the intersections Ca and Cb; detour searching means for searching said map data to identify a plurality of detour routes, each detour route departing from said set route, passing through the designated detour point and returning to the set route at a respective one of a plurality of said intersections of said array within said set detour search area; route selecting means for selecting one of said plurality of detour routes as a selected detour route for which guidance is to be provided; and route guiding means for providing guidance along the set route, as modified by the selected detour route.