Shape Memory Alloy Actuator Fracture for Tunable Temperature Activation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current actuators, such as melting eutectic devices and FRANGIBOLT®, are not tunable to a broad range of temperatures, require power and signals for activation, and generate shrapnel that can damage sensitive components, necessitating repair or replacement.
Innovation Solution
A mechanical actuator using a shape memory alloy member that can be configured to fracture at a predetermined temperature range, exerting force on an interface portion to actuate an object, which is simple, safe, and easy to tune for activation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If melting eutectic alloys or energetic devices are used for actuation, then actuation can be achieved at specific temperatures, but the devices are not tunable to a broad range of temperatures and generate shrapnel that damages sensitive components
Solution Approach 1:
The patent utilizes shape memory alloys with adjustable transformation temperatures, allowing the actuator to be tuned to operate across a broad temperature range (e.g., 100°C to 500°C) by selecting different alloy compositions, thereby achieving adaptability without generating harmful shrapnel
Solution Approach 2:
The patent replaces energetic devices and melting eutectic alloys with a shape memory alloy-based mechanical actuation system that converts thermal energy directly into mechanical motion through phase transformation, eliminating shrapnel generation while maintaining actuation functionality
Solution Approach 3:
The patent employs composite structures combining shape memory alloy elements with conventional mechanical components (springs, pins, housings) to create a hybrid actuation system that leverages the tunable properties of shape memory alloys while using traditional materials for structural support and force amplification
2Ease of operation
If solenoid-driven actuators are used, then active initiation and control are achieved, but power and signals are required for activation
Solution Approach 1:
The shape memory alloy actuator is passive and self-actuating, requiring no external power source or control signals; it automatically responds to ambient temperature changes by undergoing phase transformation and generating mechanical motion, thereby eliminating continuous energy consumption while maintaining operational responsiveness
Solution Approach 2:
The patent exploits the reversible phase transition of shape memory alloys between austenite and martensite phases, which occurs automatically in response to temperature changes, enabling the actuator to convert thermal energy directly into mechanical work without requiring electrical power or active control systems
3Use of energy by moving object
If shape memory alloy members are used for passive initiation, then no power or signal is required, but the mechanism must reliably fracture at a predetermined temperature
Solution Approach 1:
The shape memory alloy member is pre-strained during manufacturing to a specific level that ensures it will fracture at the predetermined transformation temperature; this preliminary strain conditioning guarantees reliable actuation when the alloy undergoes phase transformation, eliminating the need for additional initiation mechanisms
Solution Approach 2:
The patent introduces geometric features such as notches, grooves, or curved stress concentration zones in the shape memory alloy member design to ensure predictable and reliable fracture initiation at the transformation temperature, enhancing the consistency and reliability of passive actuation
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 mechanical actuator provides reliable and accurate initiation of actuation across a tunable temperature range without generating shrapnel, ensuring safe and efficient operation without the need for energetic components.
Implementation Method 1
a shape memory member configured to fracture at a predetermined temperature range
Implementation Method 2
the shape memory member can be configured to fracture at a predetermined temperature range
Implementation Method 3
a spring configured to exert a force on the interface portion
Data Source
AI summary
A mechanical actuator is disclosed. The mechanical actuator can comprise an interface portion configured to interface with an object, a spring configured to exert a force on the interface portion, and a shape memory member coupled to the interface portion. The shape memory member can be configured to fracture at a predetermined temperature range. Upon fracture of the shape memory member, the force of the spring can cause the interface portion to act on the object.