Contra-Rotating Electric Helicopter for Low-Noise Hover Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electric vertical take-off and landing (eVTOL) aircraft designs are mechanically complex, expensive, and inefficient in hovering due to high disk loading, limiting their flight time and noise levels, which are critical issues for applications beyond urban air mobility.
Innovation Solution
A contra-rotating electric helicopter design with a simple and reliable architecture, where the electric motor and power source rotate with the first rotor, and a second rotor spins in contra-rotation, eliminating the need for a tail rotor and reducing disk loading, thus achieving lower noise and longer flight times using existing battery technology.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If conventional eVTOL aircraft designs are used, then high-speed forward flight capability is achieved, but hovering efficiency is poor and flight time is limited due to high disk loading
Solution Approach 1:
The aircraft is divided into multiple independent rotor systems (first rotor system and second rotor system) that can operate independently. This segmentation allows optimization of each rotor system for specific flight phases, with the first rotor system optimized for hovering and the second for forward flight, thereby improving overall hovering efficiency and extending flight time.
Solution Approach 2:
The rotor systems are designed to be dynamically adjustable, with variable pitch angles and rotational speeds. The first rotor system can adjust its pitch angle to optimize hovering performance, while the second rotor system can be adjusted for forward flight, allowing the aircraft to adapt to different flight conditions and extend operational duration.
2Speed
If conventional eVTOL aircraft designs are used, then high-speed forward flight capability is achieved, but mechanical complexity and manufacturing cost are high
Solution Approach 1:
The invention extracts and eliminates the complex mechanical transmission systems, swashplates, and linkages found in conventional eVTOL designs. By using direct-drive electric motors for each rotor system, the design removes unnecessary mechanical components, thereby reducing mechanical complexity while maintaining forward flight capability.
Solution Approach 2:
Traditional mechanical control systems (swashplates, linkages, gears) are replaced with electrically controlled systems. Each rotor system is driven by independent electric motors with electronic control, substituting complex mechanical transmissions with simpler electrical actuation, thus reducing mechanical complexity and manufacturing cost.
3Speed
If conventional eVTOL aircraft designs are used, then forward flight capability is achieved, but noise levels are high due to high disk loading and rotor speed
Solution Approach 1:
The aircraft uses multiple rotor systems instead of a single high-speed rotor system. By distributing the total thrust across several rotors operating at lower individual speeds, the design reduces noise generation while maintaining forward flight capability. The segmented rotor configuration lowers disk loading per rotor, thereby reducing noise.
Solution Approach 2:
The invention changes the operational parameters of the rotor systems, specifically operating at lower rotational speeds with larger rotor diameters. This parameter change reduces the noise generated by rotor rotation while maintaining the necessary lift and forward flight performance, thereby reducing harmful noise effects.
4Speed
If conventional eVTOL aircraft designs are used, then forward flight capability is achieved, but operating cost is high
Solution Approach 1:
Complex mechanical systems are replaced with electrically driven rotor systems. Each rotor is powered by independent electric motors, eliminating the need for complex mechanical transmissions, gearboxes, and linkages. This substitution simplifies manufacturing processes, reduces assembly complexity, and lowers overall manufacturing cost while maintaining forward flight capability.
Solution Approach 2:
The electric motor systems are designed to perform multiple functions: they can operate in hover mode, forward flight mode, and transition between modes. This multi-functionality eliminates the need for separate mechanical systems for different flight phases, reducing overall system complexity and manufacturing cost while maintaining all required flight capabilities.
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 design results in a mechanically simple, highly reliable, and quiet rotorcraft with extended flight times and reduced noise, suitable for applications requiring longer flight durations and lower noise levels, such as surveillance, photography, and cargo delivery.
Implementation Method 1
a first rotor (1410) coupled to the base of the motor; and a second rotor (1401) coupled to the output shaft of the electric motor
Implementation Method 2
The torque on the motor shaft resulting from aerodynamic drag forces on the second rotor (1401) imposes a torque on the combined body of the first rotor (1410), electric motor (1405) and power source (1420)
Data Source
AI summary
A contra-rotating electric helicopter utilizes an electric motor having a base and an output shaft and a power source. The helicopter couples the base to a first rotor, thus allowing both the base and the power source to rotate within the frame of reference of the first rotor, while a contra-rotating and coplanar second rotor is coupled to the output shaft of the electric motor.