A 5-D Localization Method for a Magnetically Manipulated Untethered Robot using a 2-D Array of Hall-effect Sensors

Area of Science:

• Robotics
• Magnetic Actuation
• Sensor Technology

Background:

• Accurate localization is crucial for untethered magnetic robots, especially in medical applications.
• Existing methods face challenges in precise positioning and orientation determination.

Purpose of the Study:

• To introduce a novel five-dimensional localization method for meso-scale magnetic robots.
• To enhance the accuracy and reliability of magnetic robot localization.

Main Methods:

• Utilized a two-dimensional array of mono-axial Hall-effect sensors to measure magnetic fields.
• Implemented a two-step process involving subtraction of electromagnet's field and differentiation of the robot's magnetic field.
• Employed an optimization method to minimize error between measured and modeled magnetic fields.

Main Results:

• Achieved a position error of 2.1±0.8 mm and an angular error of 6.7±4.3°.
• Demonstrated effective localization within a 5 cm range at 200 Hz.
• Successfully minimized interference from the external electromagnetic system.

Conclusions:

• The proposed five-dimensional localization method offers high accuracy for untethered magnetic robots.
• This technique is suitable for position feedback control in future medical robotic applications.
• The method effectively reduces electromagnetic interference for improved localization precision.