Helicopter turn coordination and heading hold mode control

US5299759A · kind A · utility

Assignee

• UNITED TECHNOLOGIES CORPORATION · US

Inventors

• Porter D. Sherman · Fairfield, US
• David Hetzler · Chattanooga, US
• Paul T. Weisser, Jr. · South Windsor, US
• Stuart C. Wright · Woodbridge, US

Key dates

• Filing date: Jun 1, 1992
• Grant date: Apr 5, 1994
• Expiry date: Jun 1, 2012

Classification

• Technology area (CPC G): Physics
• CPC primary: G05D1/0858
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A mode control (25) controls a helicopter flight control system (21) between a heading hold mode and a turn coordination mode according to switching patterns resembling the natural response of an expert pilot to flight conditions. Helicopter operating parameters (31,30) are detected (31,29) and each parameter's detected value is converted from a crisp value to a fuzzy input (100). A new mode fuzzy output is provided by applying a compositional rule of inference (105) across each fuzzy input and a composite mode selection rule base (110). The new mode fuzzy output is converted into a crisp value (112) which is used to determine whether the flight control system operates in the heading hold mode or the turn coordination mode.