Position Measurements Using Magnetic Sensors for a Shape Memory Alloy Linear Actuator

Area of Science:

• Materials Science
• Mechanical Engineering
• Robotics

Background:

• Shape Memory Alloys (SMAs) offer unique actuation capabilities.
• Accurate position and temperature sensing are critical for SMA actuator control.
• Contactless sensing methods can minimize friction and improve reliability.

Purpose of the Study:

• To design and implement a linear actuator utilizing NiTi SMAs.
• To develop a contactless position sensing system using a magnetic sensor array.
• To integrate temperature measurement using thermistors for comprehensive actuator monitoring.

Main Methods:

• The actuator design incorporates NiTi SMA wires for linear motion.
• Position is measured contactlessly via a magnetic sensor array, processing individual sensor responses.
• Temperature is monitored using an array of thermistors.

Main Results:

• The contactless magnetic sensor array provides accurate position feedback across the actuator's full range of motion.
• Signal conditioning effectively selects the closest sensor for precise readings.
• Experimental results demonstrate the system's competitive accuracy and reliability.

Conclusions:

• The developed NiTi SMA linear actuator with magnetic sensing is a viable solution for precise motion control.
• Contactless magnetic sensing effectively overcomes friction issues associated with traditional methods.
• The integrated system offers accurate and reliable performance for various applications.