| 摘要 |
PROBLEM TO BE SOLVED: To enhance the maneuverability of a vehicle by judging the road configuration in a prescribed section from the coordinates information, and performing a gear ratio control according to the given road configuration. SOLUTION: The mean curvature 8 between nodes is determined from the coordinates (xn, yn) of a node Nn set on a road. The change anglesθ1-θn of nodes N1-Nn existing in a fixed section (500m) are calculated from the present position of a car, and the mean curvatureΘis determined fromΘ=(Σ|θn|)/n. When the obtained mean curvatureΘis over the reference valueθs (10deg.) and the car speed Vp (for example, 50km/h) is exceeded downward, the region of the third speed range is widened by turning off an OD switch forcedly. This enables suppressing the up/down shift to the fourth speed range inappropriate for the necessary driving force transmission when violent speed changes are made on hilly roads, etc., and the maneuverability of the car is enhanced. |
