Multi-Capsule Endoscopy: An initial study on modeling and phantom experimentation of a magnetic capsule train



Capsule endoscopy offers increased patient comfort and improved visibility of the entire gastrointestinal (GI) tract. Besides imaging, numerous literary studies on capsule endoscopy have demonstrated drug delivery, navigation strategies, tactile sensing for tumor diagnosis, and biopsy. Yet, the size limitation hampers the availability of multiple features within a single capsule. In an effort to increase the space and functionality, we propose the use of multiple capsules.


All capsules together form a capsule-train, whose wagons are connected with magnetic push/pull forces. Magnets located on each capsule form the virtual magnetic spring. The presence of a preset gap allows for joint tasks on the targeted tissue. The gap in-between capsules also ensures ease of motion throughout the GI, while negating the risk of clinching of tissue parts in between the capsules.


Designed capsule train with two capsules successfully traveled through straight phantom without breaking connection for typical bowel speed. Also, same experiment is repeated with higher (2 × to 16 × of expected) speeds to inspect possible abrupt conditions, where capsules traveled together without any disconnection while maintaining constant distance in-between. Experiment results successfully imitate the developed magnet spring model (10–30% mismatch) even with ignored friction forces and camera pixilation errors.


As future work, we will be working on adapting the capsule train for curved trajectories and perform demonstrations on ex-vivo animal bowel models. With further development, magnetically connected multi-capsule train can be adapted to clinic for improved functionality and multitasking through the GI tract.

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  1. 1.

    Swain, P. (2003). Wireless capsule endoscopy. Gut.

    Article  Google Scholar 

  2. 2.

    Iddan, G., Meron, G., Glukhovsky, A., & Swain, P. (2000). Wireless capsule endoscopy. Nature, 405(6785), 417.

    Article  Google Scholar 

  3. 3.

    Yun, S., Kim, K., & Nam, S. (2010). Outer-wall loop antenna for ultrawideband capsule endoscope system. IEEE Antennas and Wireless Propagation Letters, 9, 1135–1138.

    Article  Google Scholar 

  4. 4.

    Faerber, J., Cummins, G., Pavuluri, S. K., Record, P., Rodriguez, A. R. A., Lay, H. S., & Desmulliez, M. P. Y. (2018). In vivo characterization of a wireless telemetry module for a capsule endoscopy system utilizing a conformal antenna. IEEE Transactions on Biomedical Circuits and Systems, 12(1), 95–105.

    Article  Google Scholar 

  5. 5.

    Hintea, S., Simion, E., & Festila, L. (1996). Radio frequency link used in partially-implanted auditory prosthesis. In Proceedings of Third International Conference on Electronics, Circuits, and Systems (Vol. 2, pp. 1143–1146 vol.2).

  6. 6.

    Stewart, F. R., Qiu, Y., Lay, H. S., Newton, I. P., Cox, B. F., Al-Rawhani, M. A., & Cochran, S. (2017). Acoustic sensing and ultrasonic drug delivery in multimodal theranostic capsule endoscopy. Sensors, 17(7), 1–24.

    Article  Google Scholar 

  7. 7.

    Le, V. H., Leon-Rodriguez, H., Lee, C., Go, G., Zhen, J., Nguyen, VDu., & Park, S. (2016). A soft-magnet-based drug-delivery module for active locomotive intestinal capsule endoscopy using an electromagnetic actuation system. Sensors and Actuators A: Physical, 243, 81–89.

    Article  Google Scholar 

  8. 8.

    Woods, S. P., & Constandinou, T. G. (2013). Wireless capsule endoscope for targeted drug delivery: mechanics and design considerations. IEEE transactions on bio-medical engineering, 60(4), 945–953.

    Article  Google Scholar 

  9. 9.

    Pipe, T., Winstone, B., Melhuish, C., Pipe, A. G., Callaway, M., & Dogramadzi, S. (2017). Toward bio-inspired tactile sensing capsule endoscopy for detection of submucosal tumors. IEEE Sensors Journal, 17(3), 848–857.

    Article  Google Scholar 

  10. 10.

    Zhao, A. J., Qian, Y. Y., Sun, H., Hou, X., Pan, J., Liu, X., & Liao, Z. (2018). Screening for gastric cancer with magnetically controlled capsule gastroscopy in asymptomatic individuals. Gastrointestinal Endoscopy, 88(3), 466–474.

    Article  Google Scholar 

  11. 11.

    Swain, P., Toor, A., Volke, F., Keller, J., Gerber, J., Rabinovitz, E., & Rothstein, R. I. (2010). Remote magnetic manipulation of a wireless capsule endoscope in the esophagus and stomach of humans (with videos). Gastrointestinal endoscopy, 71(7), 1290–1293.

    Article  Google Scholar 

  12. 12.

    Valdastri, P., Webster, R. J., Quaglia, C., Quirini, M., Menciassi, A., & Dario, P. (2009). A new mechanism for mesoscale legged locomotion in compliant tubular environments. IEEE Transactions on Robotics, 25(5), 1047–1057.

    Article  Google Scholar 

  13. 13.

    Yim, S., Gultepe, E., Gracias, D. H., & Sitti, M. (2014). Biopsy using a magnetic capsule endoscope carrying, releasing, and retrieving untethered microgrippers. IEEE transactions on bio-medical engineering, 61(2), 513–521.

    Article  Google Scholar 

  14. 14.

    Kong, K., Cha, J., Jeon, D., & Cho, D. D. (2005). A rotational micro biopsy device for the capsule endoscope. In 2005 IEEE/RSJ International Conference on Intelligent Robots and Systems (pp. 1839–1843).

  15. 15.

    Vokoun, D., Beleggia, M., Heller, L., & Šittner, P. (2009). Magnetostatic interactions and forces between cylindrical permanent magnets. Journal of Magnetism and Magnetic Materials, 321(22), 3758–3763.

    Article  Google Scholar 

  16. 16.

    S.D. Senturia. (2001). Microsystem Design

  17. 17.

    Kellow, J. E., Borody, T. J., Phillips, S. F., Tucker, R. L., & Haddad, A. C. (1986). Human interdigestive motility: variations in patterns from esophagus to colon. Gastroenterology, 91(2), 386–395.

    Article  Google Scholar 

  18. 18.

    Gao, P., Yan, G., Wang, Z., Wang, K., Jiang, P., & Zhou, Y. (2011). A robotic endoscope based on minimally invasive locomotion and wireless techniques for human colon. The International Journal of Medical Robotics and Computer Assisted Surgery, 7(3), 256–267.

    Article  Google Scholar 

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Correspondence to Furkan Peker.

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Peker, F., Ferhanoğlu, O. Multi-Capsule Endoscopy: An initial study on modeling and phantom experimentation of a magnetic capsule train. J. Med. Biol. Eng. (2021).

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  • – Capsule endoscopy
  • Distance control
  • Magnetic equilibrium
  • Physical modeling
  • Gastrointestinal treatment