Hybrid analog digital control method and apparatus for estimation of absolute velocity in active suspension systems
US4953089A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 9, 1988 |
| Grant date | Aug 28, 1990 |
| Priority date | — |
| Expiry date | May 9, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60G2600/90
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved method and apparatus is provided for estimation of absolute velocity in active or semi-active suspension systems. A controller produces a signal estimate of absolute velocity which can be implemented by a control algorithm to attenuate motion between spaced members, such as in vehicular suspension systems. The controller performs time integration of an accelerometer input signal by an analog integrator means comprising a first-order low-pass filter. A digital feedback or offset means is utilized to stabilize the signal and constrain the constant and relatively low frequency components of the analog integrated signal about an oscillatory voltage range. A digital filter means receives the stable signal and removes selected constant and low frequency components of the signal to produce a signal indicative of absolute velocities for a frequency range of interest further stabilized about a select mid-range voltage value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.