Force calculation for localized magnetic driven capsule endoscopes

Wireless capsule endoscopy recently demonstrated its potential as leading technology for gastrointestinal tract examinations. Many research groups are focusing their efforts on the design of active locomotion methods to allow a complete maneuverability of the device along the gastrointestinal tract. A promising approach for locomotion is represented by master-slave magnetic coupling; however the typical large gradients of magnetic forces make device controllability very hard with important safety concerns: in this framework magnetic capsule localization and interaction force control become extremely relevant. In the present work, a preliminary on-line localization has been implemented obtaining a position feedback closed loop control of a magnetic driven capsule endoscope. Furthermore, interaction forces with the environment have been evaluated by exploiting a dedicated setup for magnetic dragging. Distributed charges-current and dipole-dipole magnetic models applied to capsule endoscopy have been investigated and results have been compared with experimentally measured magnetic forces. Advantages and limitations of employed models have been evaluated and their usability for Real-Time force calculation has been discussed.