Trimmable feel system for aircraft control
US4258890A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 3, 1978 |
| Grant date | Mar 31, 1981 |
| Priority date | — |
| Expiry date | Jul 3, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/206
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The system is used in power-assisted control systems to provide a restoring force to the control stick indicative to the pilot of the deflection of a control surface. The feel system is trimmable in that the neutral position can be altered. In prior systems trimming was accomplished by releasing a brake which permitted movement of a part of the control stick linkage toward an equilibrium position in response to the restoring force. In prior systems the released part acquired sufficient momentum to cause it to overshoot and oscillate about the equilibrium position. If the brake were engaged prematurely, the momentum was imparted to the control stick resulting in a disagreeable "kick" felt by the pilot. To overcome these problems, the brake is repetitively disengaged and engaged at a repetition rate in the range 5-40 Hz. The small amount of momentum built up in each of the successive cycles results in an almost imperceptible vibratory reaction on the control stick rather than a single large "kick". The trimming motion is damped, in effect, although no damper is employed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.