Performance Evaluation of an Outer Spiral Microrobot in Pipes in Different Environments

Capsule microrobot has the potential to replace traditional endoscopy as a means of diagnosis and treatment. We proposed an outer spiral microrobot actuated by the magnetically actuated system in our previous research. A set of three-axes Helmholtz coil is used as the magnetically actuated system to generate the uniform rotating magnetic field. The outer spiral microrobot has a variety of movement methods because of its outer shape characters. This characteristic improves the feasibility of microrobot when it moves in multiple environments of the gastrointestinal (GI) tract. This paper analyzes the movement mode of the microrobot under different conditions. An outer spiral microrobot was fabricated and evaluated through two experiments with different environments. Experimental results show that the outer spiral microrobot has different speeds in the pipe with and without fluids. This study preliminarily explores the influence on the velocity control of the outer spiral microrobot and can be used as a reference for design and control of the microrobot in the GI tract.