Method and device for computing a stabilized vehicle speed value from a pulse signal
US5243523A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1991 |
| Grant date | Sep 7, 1993 |
| Priority date | — |
| Expiry date | Mar 29, 2011 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60W2050/0052
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A method is provided for computing a stabilized vehicle speed value from a detected vehicle speed pulse signal and a detected engine speed signal, the vehicle speed value being for use by a vehicle speed control system. The method comprises several continuous cyclic steps commncing with generating a measured vehicle speed value from the detected vehicle speed pulse signal and generating a measured engine speed value from the detected engine speed signal. A current gear ratio is calculated from the measured vehicle speed value and the measured engine speed value. This current gear ratio is then passed through a single pole digital filter to filter changes in the gear ratio between consecutive cycles as a function of the current gear ratio and the gear ratio computed in the last preceding cycle of the computation. A current usable gear ratio is generated which is changed from the most recently generated usable gear ratio only if changes in the gear ratio exceed predetermined limit values. Otherwise the current usable gear ratio is unchanged from its most recently generated value. A stabilized predicted vehicle speed value is then computed from the measured engine speed and the curren…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.