A fast algorithm for field computation in magnetic guidance

The magnetic guidance is useful for extraction of ferromagnetic materials from the human body. It is also used for guiding catheters to perform non-invasive surgery in brain or blood vessel these years. We have proposed a magnetic guiding method for an active capsule endoscope to examine gastrointestinal tract. This system needs to make real-time control of the magnetic field for actuation and guidance. In this paper, we introduce a fast algorithm to compute the magnetic field and the field derivatives of an arbitrary point in the working space. Experimental results show that the algorithm has a satisfying speed and accuracy.