Abstract —This paper proposed a multidimensional information monitoring method for a novel master-slave robotic vascular interventional system. We have designed a contact force sensor based on pressure sensitive rubber to transmit the force information to surgeon to improve the security during VIS (vascular interventional surgery). Furthermore, the motion information of catheter is also monitored in the information monitoring system. The multidimensional information monitoring system can also send out a warning message to remind the operator of the danger. The simulation experiments (in vivo) have been carried out to verify the information monitoring system. And, we got the force information by the contact force sensor when the catheter contacted with the blood vessel. We also carried out the motion monitoring experiment and got the motion data of the catheter. The experimental results indicated that the information monitoring system for the master-slave system works well and can improve the security of the master-slave system. In addition, the information monitoring system can provide convenience for the operator and avoid danger when the value exceeding a threshold. Keywords: VIS (vascular interventional surgery), Catheter, Contact Force Sensor, Multidimensional Information Monitoring Method

I. INTRODUCTION In recent years, minimally invasive surgery (MIS) has

become more and more popular for the diagnosis and surgery of endovascular disease [1]. It is a revolutionary surgical technique [2]. Because it has some advantages, such as short hospital stay, less incision and less recovery time [3]. And, many diagnosis and medical surgery with an endoscope or a catheter are performed for minimum invasive surgery recently [4]. In conventional MIS, Surgeons cut an incision in

Jian Guo is with Tianjin Key Laboratory for Control Theory & Application

in Complicated Systems and Biomedical Robot Laboratory, Tianjin University of Technology, China (corresponding author to provide phone: 15102231710; e-mail: jianguo@tjut.edu.cn).

Lin Shao and Shuxiang Guo are with Tianjin Key Laboratory for Control Theory & Application in Complicated Systems and Biomedical Robot Laboratory, Tianjin University of Technology, China. Shuxiang Guo is also with the Intelligent Mechanical Systems Engineering Department, Kagawa University, Takamatsu, Kagawa, Japan. (e-mail: shaolinsdkd@163.com; guo@eng.kagawa-u.ac.jp).

Yang Yu and Qiang Gao are with Tianjin Key Laboratory for Control Theory & Application in Complicated Systems and Biomedical Robot Laboratory, Tianjin University of Technology, China (e-mail: 1625174737@qq.com; gaoanbei@163.com).

the groin and insert the catheter to the target under fluoroscopic guidance [5]. Doctors are often exposed to the X-ray radiation because that they must perform the surgery beside the patient. So the efficiency tele-surgery systems are designed to solve these problems, which can help doctors perform the interventional surgery at a safe place [6]. There are many advantages such as earliness and avoiding X-ray radiation etc. However, it requires a large of skills for the operation so that this may make the operation cannot be watched directly.

Many researches on this kind of teleoperation system have been studied [7]-[9]. There are many outstanding achievements among them. One of those researches is a robotic catheter placement system called Sensei Robotic Catheter System, which is designed by Hansen Medical Inc [10]-[11]. This system not only can provide the surgeon higher stability but also afford more accurate feedback force in the progress of catheter insertion. This system can improve manipulation accuracy and reduce X-ray radiation to the doctor. Kern T.A. and Werthschutzky R. et al proposed a design of a haptic display for catheterization [12]. They proposed that a novel assistance-system intends to provide measured force data from the tip of a guide wire and display them as feedback to the performing surgeon. They referred to design methods and the actual structure of the display. Guiatni M. and Riboulet V. et al have presented a new interface for minimally invasive surgery (MIS) training that incorporates novel broadband sensory modalities that include visual, force, and thermal technology, into the evolution of the next generation of surgical robotics and simulators [13]. Talasaz A. and Patel R.V. et al have presented investigates the relevance of force feedback (presented visually as well as directly) during tactile sensing (presented visually only) for tumor localization using an experimental setup close to one that could be applied for real robotics-assisted minimally invasive surgery [14]. Puangmali Pinyo and Althoefer K. et al proposed force and tactile sensing for minimally invasive surgery. They reviewed the state-of-the-art in force and tactile sensing technologies applied in minimally invasive surgery and discussed several sensing strategies. Although these systems can realize information display, they only have tactile feedback while lack visual monitoring or the information is unitary.

In this paper, we have proposed a multidimensional information monitoring method for a novel master-slave vascular interventional system. Furthermore, we designed a multidimensional information monitoring system for the novel master-slave catheter operating system. We designed a contact force sensor based on pressure sensitive rubber to transmit the force information to surgery to improve the

A Multidimensional Information Monitoring Method for a Novel Robotic Vascular Interventional System Jian Guo, Lin Shao, Shuxiang Guo, Yang Yu and Qiang Gao

978-1-4673-9104-7/15/$31.00 ©2015 IEEE

Proceeding of the 2015 IEEEInternational Conference on Information and Automation

Lijing, China, August 2015

609

security of VIS. The motion information and force information is displayed in the multidimensional information monitoring system. The displayed information is comprehensive. The simulation experiments have been carried out to verify the information monitoring system. We got the force information by the contact force sensor when the catheter contacted with the blood vessel.

II. THE NOVEL ROBOTIC CATHETERIZATION SYSTEM

A. Outline of the master-slave system The master-slave system mainly contains a master side and a slave side. It is a closed-loop system, which can improve the safety of the vascular interventional surgery. The master controller will collect motion information of the catheter to transmit to the slave side when the surgeon operates the catheter. At the same time, the slave side will collect the force information and transmit the information to the master side, which can form a close-loop system. The conceptual diagram of the master-slave robotic catheter system is shown in the Fig.1. In the Fig.1, the robot catheter system mainly contains a master side and a slave side this two parts. When the surgeon operates a real catheter through viewing a monitor on the master side, the controller will gather the motion information of the catheter and transmit to the slave side. The slave controller will control the motors to drive the catheter to insert when receiving the motion information from master side. The slave side will follow the motion of the master side. At the same time, an IP camera is used to transmit the information of the operation process in the operating room to the master side for visual feedback. And the contact force information between the catheter and the blood vessel wall will be detected and transmitted to the information monitoring system on the master, which can improve the safety of the surgery. Furthermore, the motion information of the catheter will be transmitted to the information monitoring system. In this case, the operator can get comprehensive information. In the meantime, the Load Cell will detect the reacting force to the catheter and transmit to the surgeon’s hand as tactile feedback.

Fig.1 The conceptual diagram of the master-slave robotic catheter system

B. The master manipulator The master side is an operating platform used to get the operating information of the surgeon. Our team presented the master-slave catheter system in the previous study [16]. The

Fig.2 shows the diagram of the master manipulator. The doctor can operate a real catheter on the master side as the conventional catheter interventional surgery, which can help the operator get the skills and experience from the conventional interventional surgery. The master side mainly realizes two tasks. Firstly, the master side can acquire the motion information of the catheter. The motion information includes the axial information and radial information. Secondly, the master manipulator can realize the force feedback using a hap-tic feedback device. The hap-tic feedback device is a damper based on the MR (magneto-rheological) fluid. The damper can produce a controlled damping force through changing the current of the coil. The MR fluid is an important material to realize the force feedback because it has some advantages such as low power consumption and short response time.

Fig.2 The master manipulator

C. The slave manipulator The slave side can realize the motion of the catheter and the force feedback. When the catheter is inserted with difficulty or the branch of blood vessel appears, the operator should rotate the catheter to insert the catheter forward. The motion of the surgical catheter on the slave side is synchronous with the catheter on the master side. Fig.3 shows the designed slave manipulator.

Fig.3 The slave manipulator

The operation to the catheter mainly contains axial motion and radial motion two degrees of freedom. The linear displacement sensor can acquire the axial motion information

610

of the catheter. The optical encoder installed on the torque motor is used to detect the radial angle of the catheter. The slide platform is fixed on the supporting frame which can change the interventional angle from 0°to 45° easily. The master side mainly contains the motor driving unit and the force detecting unit. The motor driving unit can drive the catheter moving along the axial direction and the radial direction. The force detecting unit completes to detect the reacting force and transmit to the master side to realize force feedback. Two graspers mainly realize imitating the surgeon’s grasping action. Fig.4 shows the clamping method of the graspers. The catheter will be fixed with the motor driving unit when the grasper1 clamps the catheter and the grasper2 releases. In this case, the catheter will have the synchronous movement with the motor driving unit. So the motor driving unit can drive the catheter moving or rotating on the slave side. On the contrary, the catheter will keep its position when the grasper1 releases and the grasper2 clamps the catheter. At the same time, the motor driving unit can return to original position for next movement. The catheter can be inserted to the lesion location through the process above in alternate cycle.

Fig.4 The clamping method of graspers

Ⅲ. THE MULTIDIMENSIONAL INFORMATION MONITORING

SYSTEM

A. The multidimensional information monitoring

interface

The multidimensional information monitoring interface can provide the visual feedback to the operator through displaying the motion information and the force information of the catheter. This system can display the information to surgeon more roundly, which can improve the safety of the surgery. Fig.5 shows the multidimensional information monitoring interface.

As is shown in the Fig.5, The multidimensional information monitoring interface mainly contains force information display part and motion display part. In addition, the multidimensional information monitoring interface also has a serial port initialization unit. The force information display part contains a contact force display unit and a sensor array information display unit. The contact force refers to the acting force between the tip of the catheter and the blood vessel. It is detected by a fiber optic sensor. The contact force display unit mainly contains a progress bar and a warning bar. The progress bar can display the magnitude of force vividly. The warning bar has three colors: green, yellow and red. These three colors represent three states respectively: safe, warning and danger. The sensor array information display unit can display the force detected by the sensor array based

on the pressure sensitive rubber. The motion display part can display the axial movement information and the radial movement information of the catheter. The serial port initialization unit is used to select the serial port number and initialize the interface. The working process of the multidimensional information monitoring system is shown in the Fig.6.

Fig.5 The multidimensional information monitoring interface

Fig.6 The working process of the multidimensional information monitoring

system

B. The designed sensor array

In order to detect the contact force between the lateral wall of blood vessel and the catheter, we designed a sensor array based on the pressure sensitive rubber. Fig.7 shows the sketch map of the sensor array. The sensor array mainly contains copper electrode and pressure sensitive rubber. The number of the copper electrode is 6, and the number of the pressure sensitive rubber is 9. Three copper electrodes are used as row address strobe signal; the other three copper electrodes are used as column address strobe signal. We can select any one of the pressure sensitive rubbers through the copper electrodes. Fig.8 shows the physical map of the sensor array.

611

Fig.7 The force sensor on the tip of the catheter

(a) The front view of (b) The rear view of

the sensor array the sensor array

(c) The sensor array installed on the catheter Fig.8 The physical map of the sensor array

Compared with other research, the multidimensional

information monitoring interface can display the information more comprehensive. Some studies only have haptic feedback while lack visual monitoring or the information is unitary. The multidimensional information monitoring interface will give a caution to the operator when some value exceeds the permitted range, which can help to improve the safety of the surgery.

Ⅳ. EXPERIMENTS AND RESULTS

Force feedback plays an important role in the vascular interventional surgery to improve safety. We have done the experiment to evaluate the performance of the sensor array. In order to get the pressure act on the pressure sensitive rubber, we performed a calibration experiment of the pressure sensitive rubber. Fig.9 shows the result of the calibration experiment of the sensor array. As is shown in the Fig.9, we can see that the voltage has little change when the pressure is greater than 1N.

We got the relationship of between the pressure act on the pressure sensitive rubber and the voltage of the pressure sensitive rubber. The fitting formula of sensor1 is shown as follows.

3 2-0.031 0.303 -1.121 1.694pF V V V= + + (1)

Where pF refers to the pressure act on the sensor1; V is the voltage of the sensor1. We just shows on fitting formula owing to the number is large. We can get the contact force act on the sensor array according to the fitting formula of every sensor after we got the voltage of the sensor array.

Fig.9 The experiment result

In order to get the contact force detected by the sensor array, the evaluation experiment of the sensor array was done. Due to the multidimensional information monitoring interface can only display one value at any moment, so we collect a series of data to draw the curve. Fig.10 shows the experiment of the multidimensional information monitoring system. Fig.11 shows the result of the evaluation experiment of the pressure sensitive curve. As is shown in the Fig.11, the nine curves represent the data of the pressure sensitive rubber of the sensor array respectively. Fig.12 shows the data curve detected by the fiber optic sensor. The place having larger change in the curve indicates that the catheter encounters the branch of the blood vessel. And the motion monitoring experiment was also carried out. Fig.13 shows the curve of the motion monitoring.

Fig.10 Experiment of the multidimensional information monitoring system

Fig.11 The data curve of the sensor array

612

Fig.12 The data curve of the fiber optic sensor

Fig.13 The result of motion information monitoring

We can get some information from these figures. In the Fig.11, we can see that it has a rising trend in the middle of the figure, which indicates that the catheter tip encounters the branch of the blood vessel. According to the doctor's clinical experience, the experimental result is effective when the error is lower than 0.5N. In the same way, the catheter also encounters the branch of the blood vessel in the Fig.12. In the Fig.13, the curve shows the forward motion of the catheter.

Ⅴ. CONCLUSIONS

In this paper, we proposed a multidimensional information monitoring method for a novel master-slave robotic vascular interventional system. And we have a brief introduction of the novel master-slave catheter system. We proposed a novel sensor array based on the pressure sensitive rubber to detect the contact force between the blood vessel wall and the catheter. The simulation experiments were carried out to verify the sensor array. We got the force information by the sensor array when the catheter contacted with the blood vessel. The motion monitoring experiment was also carried out and the motion data was collected. The experimental results indicated that the information monitoring system for the master-slave system works well and the sensor array can get the force information, which can improve the security of the master-slave robotic catheterization system.

Ⅴ. ACKNOWLEDGEMENT

This research is supported by National High Technology Research Development Plan (863 Plan: 2015AA040102) and General Research Program of the Natural Science Foundation of Tianjin (13JCYBJC38600) and the Project-sponsored by SRF for ROCS, SEM.

REFERENCES [1] Ji Ma, Berkelman, Peter, “Task evaluations of a compact laparoscopic

surgical robot system,” 2007 IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 398 - 403, 2007.

[2] Jian Guo, Shuxiang Guo, Nan Xiao, Xu Ma, Shunichi Yoshida, Takashi Tamiya and Masahiko Kawanishi, “A Novel Robotic Catheter System with Force and Visual Feedback for Vascular Interventional Surgery,” International Journal of Mechatronics and Automation, vol. 2, No. 1, pp. 15-24, 2012.

[3] Tanev, T.K., Sofia, Bulgaria, “Minimally-invasive-surgery parallel robot with non-identical limbs,” 2014 IEEE/ASME 10th International Conference on Mechatronic and Embedded Systems and Applications (MESA), pp. 1-6, 2014.

[4] Jian Guo, Nan Xiao, Shuxiang Guo, Tamiya, T., “A force display method for a novel catheter operating system,” 2010 IEEE International Conference on Information and Automation, pp. 782-786, 2010

[5] X. Wang, X. Duan, Q. Huang, H. Zhao, Y. Chen and H. Yu, “Kinematics and Trajectory Planning of a Supporting Medical Manipulator for Vascular Interventional Surgery,” Proceedings of the 2011 IEEE/ICME International Conference on Complex Medical Engineering, pp. 406-411, 2011.

[6] M. Tanimoto, F. Arai, and T. Fukuda, “Telesurgery System for Intravascular Neurosurgery,” Medical Image Computing and Computer-Assisted Intervention - MICCAI, pp. 29-39, 2000.

[7] Tanimoto M., Arai F., Fukuda T. and Negoro, M., “Augmentation of safety in teleoperation system for intravascular neurosurgery: a new control strategy for force display based on the variable impedance characterization,” 1998 IEEE International Conference on Robotics and Automation, pp. 2890-2895, 1998.

[8] Tanimoto M.， Arai, F.， Fukuda T. and Negoro M., “Force display method to improve safety in teleoperation system for intravascular neurosurgery,” 1999 IEEE International Conference on Robotics and Automation, pp. 1050-4729, 1999.

[9] Weijian Shang, Hao Su, Gang Li and Fischer G.S., “Teleoperation system with hybrid pneumatic-piezoelectric actuation for MRI-guided needle insertion with haptic feedback,” 2013 IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 4092-4098, 2013.

[10] Willems S, Steve D, Servatius H, Hoffman B, Drewitz I, Llerleile K, Ali Aydin M, Wegscheider K, Salukhe T, Meinertz T, Rostock T, “Persistence of Pulmonary Vein Isolation After Robotic Remote-Navigated Ablation for Atrial Fibrillation and its Relation to Clinical Outcome,” Journal of Cardiovascular Electrophysiology, vol. 21, No. 10, pp. 1079-1084, 2010.

[11] Di Biase L, Wang Y, Horton R, Gallinghouse J, Mohanty P, Sanchez J, Patel D, Dare M, Canby R, Price L, Zagrodzky J, Bailey S, Burkhardt D, Natale A, “Ablation of Atrial Fibrillation Utilizing Robotic Catheter Navigation in Comparison to Manual Navigation and Ablation: Single-Center Experience,” Journal of Cardiovascular Electrophysiology, vol. 20, No. 12, pp. 1328-1335, 2009.

[12] Kern T.A. and Werthschutzky R., “Design of a haptic display for catheterization,” Proceedings of the First Joint Eurohaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems, pp. 477-478, 2005.

[13] Guiatni M., Riboulet V., Duriez, C. and Kheddar, A., “A Combined Force and Thermal Feedback Interface for Minimally Invasive Procedures Simulation,” IEEE/ASME Transactions on Mechatronics, Vol. 18, No. 3, pp. 1083-4435, 2012.

[14] Talasaz A. and Patel R.V., “Integration of Force Reflection with Tactile Sensing for Minimally Invasive Robotics-Assisted Tumor Localization,” IEEE Transactions on Haptics, Vol. 6, No. 2, pp. 217-228, 2013.

[15] Puangmali Pinyo, Althoefer K., Seneviratne L.D. and Murphy Declan, “State-of-the-Art in Force and Tactile Sensing for Minimally Invasive Surgery,” Sensors Journal, Vol. 8, No.4, pp. 371-381, 2008.

[16] J. Guo, P. Wang, S. Guo, L. Shao and Y. Wang , “Feedback Force Evaluation for a Novel Robotic Catheter Navigation System,”Proceedings of 2014 IEEE International Conference on Mechatronics and Automation, pp.303-308, August 3-6,Tianjin, China, 2014.

613