Hydrofoil Appendage Control via Magnetohydrodynamic Flow Sensing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing hydrofoil control systems are inefficient in maintaining a horizontal position during navigation, especially in high-speed transverse water flows and rough seas, due to limitations in distance sensing and inability to detect transverse water flows, leading to jolts and tilts.

Innovation Solution

A method and apparatus that utilize a magnetohydrodynamic flow sensor to detect transverse water flow speed, calculate the difference in lift forces between port and starboard appendages, and adjust their position to cancel out lift differences, ensuring the hydrofoil remains horizontally aligned through continuous movement of the appendages.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional distance sensors are used to detect water surface distance, then the control system can maintain basic navigation, but it cannot detect transverse water flows and maintain horizontal position in rough seas

Engineering Contradiction:
Improvewater flow detection capabilityVSAvoidsensor system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces conventional mechanical distance sensors with a magnetohydrodynamic flow sensor that uses electromagnetic principles to detect water flow velocity. This substitution enables detection of transverse water flows that were previously undetectable, while the sensor integrates into the existing hull structure without adding significant complexity

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

Solution Approach 2:

The invention changes the detection parameter from distance measurement to flow velocity measurement. By measuring the velocity of transverse water flows and converting this to apparent wind angle information, the system gains the ability to detect and respond to rough sea conditions that conventional distance sensors cannot sense

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the hydrofoil navigates in foilborne condition with high speed, then navigation efficiency improves, but the hydrofoil becomes more sensitive to transverse water flows causing jolts and tilts

Engineering Contradiction:
Improvenavigation speedVSAvoidhorizontal position stability
Core Design Contradiction:
ProductivityVSStability of the object's composition

Solution Approach 1:

The patent implements a feedback control system where the magnetohydrodynamic sensor continuously measures transverse water flow velocity, the control unit calculates the apparent wind angle and required correction, and the appendage positioning system adjusts the hydrofoil's orientation in real-time. This closed-loop feedback enables the high-speed hydrofoil to automatically compensate for transverse flows and maintain horizontal stability

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The invention makes the hydrofoil's appendages dynamically adjustable rather than fixed. By continuously modifying the position and orientation of the appendages in response to real-time flow measurements, the system can adapt to changing sea conditions while maintaining high navigation speed and horizontal stability

Inventive Principle:
Principle #15Dynamics

3Device complexity

If the appendages are fixed in position, then the structure is simple, but the hydrofoil cannot compensate for transverse water flows and maintain optimal lift

Engineering Contradiction:
Improveappendage positioning systemVSAvoidlift force consistency
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The control unit receives real-time velocity data from the magnetohydrodynamic sensor and automatically calculates the necessary appendage adjustments to compensate for transverse flows. This feedback mechanism ensures consistent lift force generation by dynamically positioning the appendages to counteract flow disturbances

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent makes the appendages serve multiple functions: they provide lift during normal operation and simultaneously act as adjustable surfaces for compensating transverse water flows. This multi-functionality allows the same structural elements to maintain both structural simplicity and reliable lift consistency under varying conditions

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

This solution effectively stabilizes the hydrofoil's position, reducing jolts and tilts, and maintains optimal lift control even in challenging sea conditions, providing a more intuitive and reliable operation.

Implementation Method 1

a magnetohydrodynamic sensor mechanically fixed to the hull and configured for detecting a velocity of the water flow along a transverse direction

Methodology Applied
Scientific EffectMagnetohydrodynamic effect: Magnetohydrodynamic Effect

Implementation Method 2

such appendages are capable of interacting with a water flow in which they advance, converting the pressure resulting from the relative speed between that of advancement of the hydrofoil and that of the water flow into a lift force directed upward

Methodology Applied
Scientific EffectHydrodynamic lift: Aerofoil

Data Source

PatentEP3885246B1Method for controlling the position of a hydrofoil, hydrofoil and apparatus for controlling the position of said hydrofoil
Publication Date: 2023.11.01 INESSE CORP LTD
  • EP3885246B1 patent drawingFigure 1
  • EP3885246B1 patent drawingFigure 2
  • EP3885246B1 patent drawingFigure 3A~3B

AI summary

Method for controlling the position of a hydrofoil (1), such method providing for a detection step, in which at least one flow sensor (6) detects at least one speed measurement of a water flow movable along a transverse direction (F) and generates a corresponding flow signal (SF), a first calculation step, in which an electronic control unit (7) receives the flow signal (SF) and calculates a corresponding difference of lift (ΔP) between a first lift force (P1) of a port appendage (4') and the second lift force (P2) of a starboard appendage (4"), a second calculation step, in which the electronic control unit (7) calculates a movement position (PM) in which each appendage (4) is moved, in which the difference of lift (ΔP) is substantially zero, a driving step, in order to drive the actuator means (5) to move each appendage (4), a movement step in which the actuator means (5) move each appendage (4) in order to reach the corresponding movement position (PM) independently with respect to the other of the two appendages (4).