A Novel Relative Position Estimation Method for Capsule Robot Moving in Gastrointestinal Tract

Area of Science:

• Robotics
• Medical Imaging
• Gastroenterology

Background:

• Capsule robots offer non-invasive gastrointestinal (GI) tract examination.
• Current absolute positioning methods lack relevance in the GI tract's unstructured environment.
• Accurate tracking is crucial for effective capsule robot navigation and intervention.

Purpose of the Study:

• To develop a relative position estimation method for capsule robots in the GI tract.
• To provide a position description method that aligns with the GI tract's structure.
• To enable physicians to guide medical instruments using capsule robot insertion distance.

Main Methods:

• Obtain absolute position using magnetic tracking.
• Determine robot movement status and direction along the GI tract.
• Fit the movement trajectory using Bézier curves and evaluate distance via integration.

Main Results:

• The proposed method provides relative distance estimation for capsule robots.
• It enables direct guidance of medical instruments based on insertion distance.
• No external reference tracking objects are required on the patient.

Conclusions:

• The relative position estimation method effectively tracks capsule robot movement distance in the GI tract.
• This approach overcomes limitations of absolute positioning in unstructured environments.
• The method facilitates practical clinical applications by providing actionable insertion distance data.