| 摘要 |
PURPOSE:To enable the discriminating of right turn and left turn of a vehicle accurately, by determining a curvature radius and the current vehicle speed when a vehicle travels curving for a specified distance. CONSTITUTION:A CPU 7 judges that a vehicle makes a curves when it curves beyond a fixed angle (e.g., 40 deg.) in traveling a fixed distance (e.g., 15m). But when the curvature radius at the curving is below a fixed value (e.g., 3.5m) as criterion of reference min. rotation radius and the vehicle speed is above a fixed value (e.g., 40[km per hour]) as criterion of max. speed, a vehicle is not judged to make a curve. Judgement on the right or left turn can be made from increase or decrease in the bearing of the vehicle. The curvature radius can be determined from the distance for which the vehicle curves and the angle (radian) between bearing lines of the vehicle at both ends of the curve. This enables accurate judgement on the right or left turn free from any error in an output data of an earth magnetism sensor 1 due to disturbance. |
