| 摘要 |
PURPOSE:To contribute to safe driving by operating the actual velocity and direction of the wind on the basis of the velocity of the wind in the directions X and Y. CONSTITUTION:The X-direction component VX and Y-direction compoent VY of the wind on a vehicle 1 are detected based on the difference in the phase of each unit of a transmitter-receiver composed of ultrasonic wave transmitting units 2XS and 2YS and of receiving units 2XR and 2YR of the vehicle 1. When the component VX is to be detected, for example, the transmitting unit 2XS transmits an output from a transmitting circuit 3X, while an output of reception of the receiving unit 2XR is delivered to a receiving circuit 4X. A time-difference detecting circuit 7X detects the time of propagation TX from the difference in the phase of a transmission signal XS and a reception signal XR. An operation circuit 8X finds the velocity of propagation V1 based on the time TX and the distance lX between the transmitting and receiving units. And, an operation circuit 9X finds the component VX from the velocity V1, vehicle velocity VV and sound velocity VC. The Y-direction component VY of the wind can be determined in the same way. |
