A Method for Improving the Wearability of Capsule Positioning System Using Particle Filter

Ingestible capsules with position tracking capabilities bring a significant advancement in the diagnosis and treatment of gastrointestinal disorders. However, the wearability of these capsule positioning systems is restricted by the weight and shape of the transmitter (Tx). To enhance the wearability and flexibility of the system, a novel positioning system using particle filter (PF) is proposed. By employing PF, the system can calculate the capsule’s position in 3D space using only a belt-shaped Tx coil, paired with a single Rx coil and an inertial measurement unit (IMU). PF iteratively updates the estimated position based on the capsule movement and changes in mutual inductance (MI). The performance of PF with different noises is analysed. Simulation results show that the system has a 22.5 × 11.5 × 27 cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> field of view (FOV), a root mean square error (RMSE) of 13.89 mm under noise.