Rotorcraft Blade Pitch Feedback for Vertical Takeoff on Slopes

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Rotorcraft takeoff on sloping terrain is challenging due to the need for precise control of lift rotors to achieve vertical lift while avoiding sliding, which is complicated by the lack of effective piloting aids, especially on remote or automatic piloting systems, and can lead to rotor damage from improper pitch positioning.

Innovation Solution

A method and system that measure and automatically control the pitches of rotor blades during landing to optimize their position for takeoff, using data from landing phase measurements to adjust collective and cyclic pitches, ensuring a balanced and vertical takeoff by positioning the rotor discs appropriately relative to the slope and wind conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the rotorcraft uses remote or automatic piloting systems, then the piloting complexity is reduced, but the ability to sense and adjust rotor positions according to slope conditions is lost

Engineering Contradiction:
Improvepiloting complexityVSAvoidfeedback on rotor position
Core Design Contradiction:
Ease of operationVSLoss of information

Solution Approach 1:

The patent implements feedback by using sensors to detect the actual position of rotor discs during landing and using this detected information to automatically calculate and adjust the optimal rotor positions for takeoff, thereby compensating for the lack of pilot sensation in remote or automatic piloting modes

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system performs self-service by automatically detecting landing conditions, calculating optimal takeoff configurations, and positioning the rotor discs without requiring pilot intervention, enabling remote or automatic piloting systems to handle slope operations independently

Inventive Principle:
Principle #25Self-service

2Stability of the object's composition

If the lift rotor is maintained in a horizontal position during landing on slope, then the rotorcraft stability is improved, but the rotor mast may be damaged due to excessive forces

Engineering Contradiction:
Improverotorcraft stabilityVSAvoidrotor mast strength
Core Design Contradiction:
Stability of the object's compositionVSStrength

Solution Approach 1:

The patent applies dynamics by transitioning the rotor disc position from a static horizontal orientation during landing to a dynamically adjusted position during takeoff, where the rotor plane is tilted relative to the horizon based on the slope angle detected during landing, thereby distributing forces more favorably on the rotor mast

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the parameter of rotor disc orientation by detecting the slope angle during landing and calculating a corresponding takeoff configuration where the rotor plane forms a specific angle with the horizon, optimizing both stability and structural loads

Inventive Principle:
Principle #35Parameter changes

3Manufacturing precision

If the pilot manually adjusts rotor positions during takeoff on slope, then the takeoff precision is improved, but the pilot workload increases significantly

Engineering Contradiction:
Improvetakeoff precisionVSAvoidpilot workload
Core Design Contradiction:
Manufacturing precisionVSEase of operation

Solution Approach 1:

The system performs self-service by automatically detecting landing conditions, calculating optimal takeoff configurations, and positioning the rotor discs without requiring pilot intervention, thereby achieving precise slope takeoff automatically

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent replaces the mechanical manual adjustment system with an automated control system that uses sensors to detect slope conditions and automatically positions the rotor discs, substituting pilot physical actions with automated mechanical control

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

4Speed

If the rotorcraft takes off vertically from sloping ground, then the takeoff speed is improved, but the rotor positioning becomes more complex

Engineering Contradiction:
Improvetakeoff speedVSAvoid rotor positioning complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by detecting and memorizing the slope angle during the landing phase, then using this pre-acquired information to automatically calculate and set the optimal rotor positions before takeoff begins, simplifying the takeoff procedure while maintaining vertical ascent capability

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3831715B1Method and system for assisting the take-off of a rotorcraft
Publication Date: 2023.01.04 EUROCOPTER FRANCE SA
  • EP3831715B1 patent drawingFigure 1~2
  • EP3831715B1 patent drawingFigure 3~6

AI summary

The present invention relates to a method and a system (60) for assisting the takeoff of a rotorcraft (1) on a slope. Said rotorcraft (1) comprises at least one lifting rotor (2) equipped with a plurality of blades (21), control devices (22, 23, 32) for the pitch of said blades (21, 31) and a landing gear equipped with at least three ground contact elements (41, 42, 43). The said method includes a step of measuring information relating to the forces experienced by each ground contact element (41,42,43) during a landing phase on said slope (100), a step of measuring at least one piece of information relating to said pitch of said blades (21) during said landing phase and a step of controlling said pitch of said blades (21) during said takeoff phase of said rotorcraft (1) following said landing according to said measurements carried out during said landing in order to allow a safe and simplified takeoff.