Tail-Rotor Actuator Damping for Fuselage Vibration Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Excess vibration within an aircraft fuselage decreases passenger satisfaction and increases wear on the aircraft's structure and equipment, primarily caused by the interaction of airflow with the tail-rotor assembly.
Innovation Solution
A tail-rotor vibration dampener system that includes a fuselage, an open rotor assembly with a powerplant and rotor blades, actuator units with hydraulic or electrically activated dampening devices, and a computerized controller to determine and cancel the vibration frequency, thereby reducing vibrations transmitted to the fuselage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the open rotor assembly is used to provide thrust and lift, then the aircraft can become and remain airborne, but vibrations are generated that decrease passenger satisfaction and increase wear on structure and equipment
Solution Approach 1:
The patent applies mechanical vibration by using a vibration dampener device that generates counter-vibrations to cancel the harmful vibrations produced by the open rotor assembly. The dampener creates vibrations at the same frequency but in opposite phase to neutralize the harmful effects while maintaining the rotor's thrust and lift generation capability
Solution Approach 2:
The patent converts the harmful vibrations into a beneficial effect by using the vibration dampener to transform the harmful oscillatory motion into useful counter-vibrations. The system takes the harmful vibration energy and converts it into a beneficial cancellation effect, improving passenger comfort and reducing structural wear without compromising aircraft performance
2Ease of operation
If the hydraulic actuator controls the position of the open rotor assembly, then the rotor position can be adjusted, but vibrations are transmitted to the fuselage
Solution Approach 1:
The patent introduces a vibration dampener as an intermediary device between the hydraulic actuator and the fuselage. This mediator absorbs and cancels the vibrations transmitted through the actuator while allowing the position control function to operate normally, thus protecting the fuselage from harmful vibrations
Solution Approach 2:
The patent extracts the harmful vibration component from the actuator system by using the vibration dampener to isolate and cancel the vibratory motions. This separates the useful position control function from the harmful vibration transmission, allowing the actuator to maintain control capability while the dampener removes the detrimental vibrations
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 effectively minimizes vibrations in the aircraft fuselage by matching and opposing the frequency of the tail-rotor vibrations, enhancing passenger comfort and reducing structural wear.
Implementation Method 1
an electrically activated hydraulic solenoid operable to create canceling vibrations within hydraulic fluid of the hydraulic actuator
Implementation Method 2
the canceling vibrations are controlled to the frequency of the vibration emanating from the open rotor assembly and to an opposite phase of the vibration emanating from the open rotor assembly
Implementation Method 3
a hydraulic actuator controlling a position of the open rotor assembly in relation to the fuselage
Data Source
AI summary
A tail-rotor vibration dampener system for an aircraft is provided. The system includes a fuselage and an open rotor assembly including a powerplant and a set of rotor blades. The system further includes at least one actuator unit connecting the open rotor assembly to the fuselage. The actuator unit includes a hydraulic actuator controlling a position of the open rotor assembly in relation to the fuselage and a dampening device operable to cancel a vibration emanating from the open rotor assembly. The system further includes a computerized vibration dampening controller, including programming to determine a frequency of the vibration emanating from the open rotor assembly and control the dampening device to cancel the vibration emanating from the open rotor assembly based upon the frequency.