Citation: Zhang, J.; Shi, B.; Feng, G.;
Zuo, G.; Liang, Y. Design,
Development and Control of a
Forming Robot for an Internally
Fixed Titanium Alloy Strip. Machines
2022, 10, 68. https://doi.org/
10.3390/machines10020068
Academic Editors: Yuansong Qiao
and Seamus Gordon
Received: 5 December 2021
Accepted: 12 January 2022
Published: 18 January 2022
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Article
Design, Development and Control of a Forming Robot for an
Internally Fixed Titanium Alloy Strip
Jiaji Zhang
1,2
, Binjun Shi
1,2
, Guang Feng
1,2
, Guokun Zuo
1,2
and Ye Liang
3,
*
1
Cixi Institute of BioMedical Engineering, Ningbo Institute of Materials Technology & Engineering, Chinese
Academy of Sciences, Cixi 315300, China; zhangjiaji@nimte.ac.cn (J.Z.); shibinjun@nimte.ac.cn (B.S.);
fengguang@nimte.ac.cn (G.F.); moonstone@nimte.ac.cn (G.Z.)
2
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences,
Ningbo 315201, China
3
Department of Oral and Maxillofacial Surgery, Center of Stomatology, Xiangya Hospital,
Central South University, Changsha 410008, China
* Correspondence: liangye@csu.edu.cn
Abstract:
Medical titanium alloys are widely used in surgery, orthopedics, stomatology and other
medical specialties because of their good biocompatibility. In traditional rigid internal fixation
applications, titanium alloy strips or plates must be bent to fit the supported surface. Currently, the
common practice is to bend titanium alloy bars in three degrees of freedom manually. However,
it is difficult to ensure bending accuracy and achieve the best shape. In this study, we introduce a
forming robot for internally fixed titanium alloy strips (FRIFTAS). The forming robot is a device that
automatically reshapes the titanium strip with various specifications according to medical needs.
Here, the design of mechanical and electrical systems and the development of the overall system
are described to illustrate how a FRIFTAS is structured and designed. Three bending experimental
tests are conducted. In the bending experiments, the robot bends an initial strip on the roll, pitch and
yaw directions independently. The results show that the robot can bend a section of the alloy strip
at the desired angle. Then, an overall reshaped titanium alloy strip experiment is discussed. The
results show that the titanium-strip-forming robot is capable of automatically reshaping an internally
fixed titanium strip. The proposed robot can perform the numerically controlled bending of the
medical titanium strip according to physicians’ personalized requirements for surgery to improve the
accuracy and efficiency of preoperative preparation and provide a better postoperative appearance
and more effectively functioning treatment scheme for patients.
Keywords:
oral and maxillofacial surgery; internally fixed titanium strip; robotic forming; digital medicine
1. Introduction
The development of digital medicine has greatly improved the accuracy and speed
of medical surgery. For example, in oral and maxillofacial surgery, widely used digital
medical technology can design models and surgical tools according to individual bone
shape. Therefore, the operation, which was completed in the surgical process, is advanced
to the preoperative stage. Regarding the new technology’s application in digital medicine,
titanium strip bending is the only existing process that has not been digitized and must
still be operated manually. The operation of this process is cumbersome, inefficient, has
poor precision and lacks repeatability.
Titanium strips are medical consumables with a special hole structure that must be
bent according to the patient’s condition. The medical titanium strip was approved by
Medical Device Approval III. Titanium strips are widely used in medicine. It must be used
after trauma and tumor surgery, and there are many product specifications.
In rigid internal fixation technology, titanium strip repair can be applied to multiple site
fractures with decent curative effects [
1
–
4
]. However, the bending of finished titanium strips
Machines 2022, 10, 68. https://doi.org/10.3390/machines10020068 https://www.mdpi.com/journal/machines
