Formation Flight Control Using Vortex Position Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional formation flight control systems inaccurately estimate the position of wingtip vortices and fail to account for vortex-induced aerodynamic effects, leading to uncommanded movements of trailing aircraft into wingtip vortices, and are slow and less responsive in achieving desired positions.
Innovation Solution
A formation flight control system that accurately estimates the position of wingtip vortices by accounting for wind effects and sensor biases, using a position module, desired position module, and control module to control the trailing aircraft's flight, incorporating a Kalman recursion process for improved responsiveness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional formation flight control systems estimate vortex position based on flight characteristics alone, then the control system is simple to implement, but the vortex position estimation is inaccurate leading to uncommanded movements of trailing aircraft
Solution Approach 1:
The patent introduces wind state parameters as an intermediary element that mediates between the leading aircraft's vortex generation and the trailing aircraft's position control. By estimating wind state (velocity and direction) separately and using it to calculate vortex position, the system achieves more accurate vortex positioning without directly complexly coupling the aircraft control systems. The wind state acts as a mediator that accounts for environmental factors affecting vortex displacement.
Solution Approach 2:
The patent replaces direct mechanical/sensor-based vortex detection with a computational estimation approach. Instead of using complex sensors to directly measure vortex position, the system substitutes a mathematical model that calculates vortex position based on flight characteristics and wind state parameters. This computational substitution achieves accurate vortex positioning while maintaining relatively simple system implementation.
2Productivity
If gradient peak-seeking approach is used to position trailing aircraft, then the control approach is simple to implement, but the response time is slow and the approach is time-consuming
Solution Approach 1:
The patent performs preliminary calculation of the optimal trailing aircraft position by directly computing the desired position based on vortex position and aerodynamic benefit criteria. Instead of gradually searching for the optimal position through iterative gradient methods, the system pre-calculates the target position using a mathematical model that considers vortex location, wind effects, and aerodynamic efficiency. This preliminary determination of the optimal position enables faster response and more direct control actions.
3Use of energy by moving object
If trailing aircraft flies close to leading aircraft for formation benefits, then aerodynamic efficiency is improved, but the trailing aircraft is affected by wingtip vortices causing flight instability
Solution Approach 1:
The patent converts the harmful wingtip vortices into a beneficial resource by positioning the trailing aircraft to utilize the updraft and reduced drag regions within or near the vortex structure. Rather than simply avoiding the vortex as a harmful phenomenon, the control system calculates and positions the trailing aircraft to exploit the aerodynamic benefits provided by the vortex flow pattern, such as reduced induced drag and favorable pressure gradients, while maintaining safe separation distances.
Solution Approach 2:
The patent implements dynamic positioning control that continuously adjusts the trailing aircraft's position relative to the leading aircraft and vortex based on real-time flight characteristics and wind conditions. The desired position is not fixed but dynamically calculated to optimize aerodynamic benefits while avoiding excessive vortex exposure. This dynamic adjustment allows the system to adapt to changing flight conditions and maintain optimal formation configuration for fuel efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system ensures accurate tracking and positioning of trailing aircraft relative to wingtip vortices, preventing uncommanded movements and enhancing operational benefits like fuel economy and range by effectively utilizing vortex-induced aerodynamic benefits.
Implementation Method 1
The benefits of formation flight may include, but are not limited to, performance advantages including aerodynamic efficiency as a result of a reduction in induced drag
Implementation Method 2
positioning the trailing aircraft into a desired position relative to the vortex... utilizing (e.g., maximizing) the operational benefit of the vortex
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
An apparatus for controlling the formation flight of a trailing aircraft relative to a vortex generated by a leading aircraft includes a position module, peak-seeking module, limiter module, and control module. The position module is configured to determine a position of the vortex relative to the trailing aircraft. The peak-seeking module is configured to determine a desired position of the trailing aircraft for providing desired vortex-induced aerodynamic benefits based on the position of the vortex relative to the trailing aircraft and a mapping function of an individual performance metric. The limiter module is configured to modify the desired position of the trailing aircraft to avoid unintended crossings of the trailing aircraft into the vortex. Finally, the control module is configured to control flight of the trailing aircraft based on one of the desired position of the trailing aircraft and modified desired position of the trailing aircraft.