Design and evaluation of shape memory alloy-actuated active needle using finite element analysis and deflection...

Area of Science:

• Medical Devices
• Robotics
• Biomedical Engineering

Background:

• Conventional needles lack active deflection capabilities, limiting accuracy and effectiveness in complex procedures.
• Obstacles in insertion paths can compromise needle-based interventions.

Purpose of the Study:

• To design and evaluate an active needle with enhanced tip deflection.
• To improve needle-based procedure accuracy and obstacle navigation.

Main Methods:

• Developed an active needle utilizing a shape memory alloy (SMA) actuator.
• Performed finite element simulations for design optimization.
• Evaluated needle deflection in tissue-mimicking gels using real-time tracking.

Main Results:

• Achieved significant tip deflections (50 mm in liver, 39 mm in prostate gels at 150 mm depth).
• Obtained low simulation errors (16.42% and 12.62%) for needle deflection.
• Demonstrated small root mean squared errors (1.42-1.47 mm) in deflection tracking.

Conclusions:

• The active needle demonstrates effective large tip deflections for bypassing obstacles.
• The needle can accurately track preplanned trajectories with minimal error.
• Finite element analysis aids in optimizing active needle design and predicting performance.