Non-Contact Actuation of Less-Invasive Bone Lengthening Device Using Embedded Cycloidal Motor Driven by Permanent Magnets from the outside

Abstract:

This report proposes a miniaturized non-contact actuation mechanism for a surgical device for bone extension operation. The device is embedded inside the body, and the device controls the gap between the bones cut by operation. A small permanent magnet is attached to the outer gear of a cycloidal reducer that rotates a screw of the screw-nut mechanism. This magnet is forced by the external magnetic flux density controlled by the outer permanent magnets’ position. In this research, two pairs of permanent magnet bar were rotated by stepping motors outside the device. The outer gear is constrained in As a result, ring gear of the cycloidal reducer is driven in translational wobbling motion the inner gear is connected to the screw and the output nut position is driven linearly with screw rotation. The dimensions of the fabricated device were 7 mm in diameter and 39.7 mm in length. The output thrust of this device was 2 N.

• Periodical: Key Engineering Materials (Volumes 523-524)
• Pages: 722-726
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.523-524.722
• Online since: November 2012
• Authors: Yuki Matsuzaki, Yoichi Kadota, Kazuo Uzuka, Hideyuki Suenaga, Ken Sasaki, Takeshi Morita
• Keywords: Bone Extension, Cycloidal Reducer, Non-Contact Drive, Permanent Magnet

References

[1] Giovanni De Bastiani, M.D., Roberto Aldegheri, M.D., Lodovico Renzi-Brivio, M.D., Giampaolo Trivella, M.D., "Limb Lengthening by Callus Distraction (Callotasis)", J. of Pediatric Orthopedics, 7(2), pp.129-34, (1987)

DOI: 10.1097/01241398-198703000-00002

[2] Yoichi Kadota, Kazuhiko Inoue, Kazuo Utsuka, Hideyuki Suenaga, Takeshi Morita, "Driving method of less invasive bone distraction device using permanent magnets without any contacts ", Proc. of the 23rd Symposium on Dynamics of Electromagnetic Devices, pp.104-107, (2011)

[3] Yoichi Kadota, Kazuhiko Inoue, Kazuo Utsuka, Hideyuki Suenaga, Takeshi Morita, "Non-contact actuation of less-invasive bone distraction device using permanent magnets", Proc. of Japan Society of Precision Engineering Spring Meeting, (CD-ROM), L34, (2011)

DOI: 10.4028/www.scientific.net/kem.523-524.722

[4] Sentoku Hirofumi, Wakamiya Kenichi, "Characteristics of Miniature Cycloidal Motor Driven by Air Pressure", Proc. of Japan Society of Mechanical Engineers, vol.5, pp.335-336, (2000)