Universal Joint Tether Untwisting for Wave-Powered Vehicles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wave-powered water vehicles face challenges in maintaining orientation and reducing tether movement in wave-bearing water, as well as managing tether entanglement and drag, which affects efficiency and safety.
Innovation Solution
A wave-powered vehicle (WPV) design featuring a float with a controllable upper member, a cable with specific cross-sectional geometry and materials to reduce drag, and mechanisms for untwisting and pressure-sensitive tether release, along with a two-axis universal joint and elastic elements to manage tether loads and entanglement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a tether connects the float and swimmer in a wave-powered vehicle, then the vehicle can transmit wave power, but the tether becomes twisted and entangled in wave-bearing water
Solution Approach 1:
The patent applies a two-axis universal joint at the float connection point that allows the tether to rotate and adapt to wave-induced movements. This dynamic mechanism enables the tether to maintain proper orientation while transmitting power, preventing twisting and entanglement during operation in wave-bearing water.
Solution Approach 2:
The patent changes the operational parameters of the tether connection by introducing rotational degrees of freedom through the universal joint. This allows the connection to accommodate varying angles and orientations caused by waves, maintaining effective power transmission while preventing tether entanglement.
2Stability of the object's composition
If the tether is kept taut to maintain vehicle orientation, then stability is improved, but drag and resistance increase
Solution Approach 1:
The universal joint provides dynamic adaptation, allowing the tether to maintain necessary tension for stability while rotating to align with the direction of motion. This reduces drag by optimizing the tether's orientation relative to water flow while maintaining sufficient tautness for vehicle stability.
3Stability of the object's composition
If the upper member of the float is fixed to maintain orientation, then stability is improved, but the float cannot adapt to wave motion
Solution Approach 1:
The upper member is connected through a two-axis universal joint that provides controlled rotational freedom. This allows the member to maintain a relatively stable orientation while adapting to wave-induced movements, combining stability with adaptability to varying wave conditions.
Solution Approach 2:
The float's upper member is segmented from the main body through the universal joint connection, allowing independent movement and orientation adjustment. This segmentation enables the upper member to respond to wave motion while maintaining its functional orientation for power transmission.
4Reliability
If the tether is made stronger to prevent breaking under load, then reliability is improved, but the tether becomes more prone to twisting
Solution Approach 1:
The universal joint dynamically manages the interaction between strong tether and wave motion, allowing the tether to maintain its strength for reliability while the joint accommodates rotational movements that would otherwise cause twisting in a rigidly connected system.
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 WPV maintains stable orientation, reduces tether movement and drag, and ensures safe disentanglement from marine obstacles, enhancing operational efficiency and safety in wave-bearing environments.
Implementation Method 1
comprises a leading edge portion and a tapered trailing edge portion, the leading edge portion including the part of the cross-section which has the greatest width
Implementation Method 2
elastic elements to manage tether loads and entanglement
Implementation Method 3
a float, (2) a swimmer, and (3) a tether connecting the float and the swimmer; the float, swimmer and tether being such that, when the vehicle is in still water, (i) the float is on or near the surface of the water
Data Source
AI summary
A float (1) suitable for use as a buoy or as a component for a wave-powered vehicle. The float (1) includes an upper member (12) whose height can be changed and/or which remained substantially vertical even when the float is in wave-bearing water. A low drag cable (2) suitable for use as a tether in a wave-powered vehicle has a streamlined cross-section and includes a tensile member (21) near the front of the cross-section, at least one non-load-bearing member (22) behind the tensile member, and a polymeric jacket (23). Wave-powered vehicles having a float (1), a submerged swimmer (3) and a tether (2) connecting the float and the swimmer, include a means for determining whether the tether is twisted; or a means (91) for untwisting the tether; or a pressure-sensitive connection (71, 72, 73) which can disconnect the tether when the vehicle is dragged downwards by entanglement with a whale; or a 2-axis universal joint securing the tether to the float or to the swimmer; or elastic elements which absorb snap loads created by the tether; or two or more of these.