Multifunctional Micro Catheter Tele-operation System for Reduction of Burden of Patients and Doctors

(1)主从机系统我们开发了一种从设备，可以独立地遥控导管和导丝。它有两个自由度，即一个用于向前和向后运动，一个用于旋转。以机械铅笔机构为例，提出了一种用于前进和后退驱动的直线驱动机构。与传统的滚子机构相比，安全性得到了提高。此外，还简化了旋转接线。通过一次敲击，导尿管的移动是电子调节的。由计算机控制选择前进或后退运动。两个方向的最小步长分辨率均为0.1 mm，定位精度大大提高。我们还安装了安全装置以释放导管。当导管直径改变时，我们会适当地更换机械紧固件。与导尿管接触的部分容易拆卸。微接触传感器我们研制了一种直径为1 mm的微接触传感器，可以安装在导管的顶端。该传感器由压电薄膜致动器以谐振频率激励。当它与物体接触时，机械阻抗发生变化，并通过压电薄膜的传感功能来检测该变化。用水热法在钛衬底上沉积了薄膜。基于接触前后阻抗的变化，成功地检测到了接触状态。(3)遥操作医疗系统我们开发了基于主从式设备的遥操作系统。我们用硅橡胶制作了一个带有内孔的透明血管模型。我们用这个模型模拟了血管内神经外科手术，并对所提出的系统进行了评估。导管到达了目标位置，我们证实了所提出的系统的有效性。

(1) Master Slave SystemWe developed a slave device to teleoperate the catheter and guide wire independently. It has two degree-of-freedom, that is, one for forward and backward motion and one for rotation. We proposed a linear drive mechanism for forward and backward drive using examples from the mechanical pencil mechanism. Compared with the conventional roller mechanism, safety is improved. Moreover, wiring for rotation is simplified. Movement of the catheter by a single knock is adjusted electronically. Forward motion or backward motion is selected by the computer control. The minimum step resolution is 0.1 mm in both directions and position accuracy is greatly improved. We also attached the safety mechanism to release the catheter. When the diameter of the catheter changes, we change the mechanical fastener appropriately. The part which contacts with the catheter is detached easily. Sterilization operation is possible by changing the fastener.(2) Micro Contact SensorWe developed a micro contact sensor of 1 mm diameter which can be set at the tip of catheter. This sensor is excited with the resonant frequency by the piezoelectric thin film actuator. When it contacts with the object, mechanical impedance is changed, and the change is detected by the sensing function of the piezoelectric thin film. The film is deposited on the titanium substrate by the hydro thermal method. We succeeded in detection of contact state based on the impedance change before and after contact.(3) Teleoperated Medical SystemWe developed the teleoperation system using a master and slave devices. We fabricated a transparent blood vessel model with inner hole with the silicone elastomer. We simulated intravascular neurosurgery with this model and evaluated the proposed system. The catheter reached the goal position and we confirmed effectiveness of the proposed system.