| 摘要 |
PURPOSE:To enable the accurate detection of the traveling direction immediately after the start of running, not being affected by an error in mounting, by computing the turning radius of a vehicle on the basis of the difference in the speed of rotation between two wheels which is caused by a steering operation, and by calculating a steering angle therefrom. CONSTITUTION:Running distance sensors 20 and 21 are formed of magnets connected to left and right rear wheels 12 and 13 respectively and of lead switches operated thereby in an ON-OFF manner, and deliver output pulses every time the rear wheels 12 and 13 rotate by a unit angle. These output pulses are inputted to CPU 23, and the respective speed of rotation of the rear wheels 12 and 13 is calculated from an output pulse per unit time and stored in RAM 25. The turning radius R is computed from the difference in the speed of rotation between them, and the direction of turning of the vehicle is determined therefrom. Although there is scarcely any difference in the speed of rotation between the rear wheels 12 and 13 in the state of straight running of the vehicle, the speed of rotation of the rear wheel 13 becomes larger than that of the rear wheel 13, for instance, when the vehicle is turned to the right. Then the absolute value of the turning radius R becomes a value corresponding to the inverse number of the difference in the speed of rotation, the sign thereof turns to be plus, and a steering angle turns to be proportional to 1/R. |
