Steering control in an aircraft equipped with a wheel drive system

Patent metadata

Field	Value
Publication number	US-9751621-B2
Application number	US-201414341742-A
Country	US
Kind code	B2
Filing date	Jul 25, 2014
Priority date	Nov 13, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

Control of aircraft steering during ground travel is provided in an aircraft equipped with an engines-off wheel drive system controllable to move the aircraft autonomously on the ground without reliance on the aircraft's main engines or external tow vehicles. The wheel drive system is designed to interact with the aircraft's nose wheel hydraulic steering system to augment or replace the hydraulic steering system with the operation of the wheel drive system at taxi speeds, particularly at very low taxi speeds and even when the aircraft is stopped, to steer the aircraft as it maneuvers through turns during ground travel between landing and takeoff and at other times.

First claim

The invention claimed is:

1. A method for controlling steering in aircraft equipped with nose landing gear wheel drive systems for autonomous ground travel that reduces or eliminates forces on the aircraft's nose landing gear hydraulic steering system when the aircraft is turned to change direction of ground travel, comprising:
a. providing an aircraft with a nose landing gear supporting a pair of nose wheels and a hydraulic nose wheel steering system controllable to swivel the nose wheels and turn the aircraft in a desired direction during ground travel;
b. mounting a wheel drive system comprising an electric drive motor controllably powered to drive and steer the aircraft during ground travel without reliance on operation of aircraft engines within each one of the pair of nose wheels;
c. providing controls for the hydraulic nose wheel steering system operable to control swiveling of the nose wheels and turning of the aircraft and controls for the wheel drive system operable to control actuation of the electric drive motor mounted within each nose wheel, speed of the aircraft during ground travel, and direction of ground travel operationally integrated with the hydraulic nose wheel steering system controls;
d. operating the wheel drive system controls to actuate the electric drive motors and move the aircraft during ground travel and operating the hydraulic nose wheel steering system controls to swivel the nose wheels and turn the aircraft when the aircraft is moved above a predetermined speed by the electric drive motors; and
e. when the aircraft is stopped or the aircraft is moving at the predetermined speed or at a speed lower than the predetermined speed during ground travel, operating only the wheel drive system controls and controlling actuation of the electric drive motors to turn and move the aircraft.

2. The method of claim 1 , further comprising providing a hydraulic nose wheel steering system controls override and overriding the hydraulic nose wheel steering system controls when the aircraft is traveling at the speed lower than the predetermined speed or the aircraft is stopped and the wheel drive systems controls are operated to change direction of ground travel of the aircraft.

3. The method of claim 1 , further comprising when said aircraft is stopped or moving at the speed lower than the predetermined speed and is required to change ground travel direction, operating the wheel drive systems controls and controlling actuation of each electric drive motor to drive one nose wheel at a slower speed than the other nose wheel, and turning the aircraft toward the nose wheel driving at the slower speed.

4. The method of claim 1 , further comprising when the aircraft is stopped, inactivating the hydraulic nose wheel steering system controls and activating the wheel drive systems controls to differentially actuate each electric drive motor to turn the aircraft in a desired direction and move the aircraft in the desired direction.

5. The method of claim 1 , further comprising selectively actuating each electric drive motor in each one of the nose landing gear wheel drive systems and driving each nose landing gear wheel independently and at a different speed when ground travel speed of the aircraft is at or lower than the predetermined speed or when the aircraft is stopped.

6. The method of claim 1 , further comprising augmenting operation of the hydraulic nose wheel steering system with operation of the nose landing gear wheel drive systems and simultaneously controlling operation of the nose landing gear wheel drive systems and the hydraulic nose wheel steering system to move the aircraft and change the aircraft direction of ground travel.

Assignees

• Cox Isaiah W
• Borealis Tech Ltd

Inventors

• Cox Isaiah W

Classifications

• B64C25/405 Primary

  Powered wheels, e.g. for taxing · CPC title

• Y02T50/823

  Cross-Sectional Technologies · mapped topic

• B64C25/50

  Steerable undercarriages; Shimmy-damping · CPC title

• Y02T50/80

  Energy efficient operational measures, e.g. ground operations or mission management · CPC title