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经食道超声扫描使用经食道超声探头由口腔进入人体食道或胃部用于心脏诊断或心脏介入手术引导。传统的经食道超声诊疗需要医生近距离手动操作超声探头，此操作高度依赖于医生的临床经验，在心脏介入手术时与X光的联合成像使超声医生处于电离辐射的危险环境下，需要穿戴沉重闷热的防护服，大大增加了医生的工作强度，上述问题导致经食道超声扫描难以得到有效推广。因此，本研究深入探究机器人化经食道超声的系统设计及遥操作控制方法，通过定制化从端机器人平台、主端控制设备及主从遥操作方法实现经食道超声扫描的有效与安全控制，具体研究内容包括：

（1）经食道超声机器人多自由度集成操控及多冗余动力传递机构的设计方法。在机器人从端结构设计中，利用与被控目标相协调的驱动结构布局方式实现主体结构的紧凑型、轻量化与模块化设计；通过在机器人中融入两个扭矩传感器使其具有双向0.45Nm的操作力感知功能；将基于定点约束样条曲线的设计思路应用于柔性软管路径引导以实现递送动力传递功能；使用可移动推车与被动串联臂将机器人与软管引导结构组合成可移动型经食道超声机器人平台。

（2）具有紧凑构型及小转动惯量的绕定点转动四自由度力反馈主手设计方法。对应于机器人的运动特点，基于锥齿轮换向原理提出了一种新型绕定点转动的四自由度力反馈双摇杆结构。使用直流无刷空心杯电机、小型一体化电机驱动器及磁场矢量控制方式实现定制化力反馈功能，支持0.086Nm的单轴力矩反馈功能。上述设计将电机置于底座平台，有效避免了电机尺寸与重量对设备整体性能的影响，具有结构紧凑，响应速度快等优点。

（3）基于数据驱动及双边控制模型的连续体机器人力触反馈及主从遥操作控制方法。针对内部结构参数未知的经食道超声柔性连续体系统，使用手轮操作力感知及基于神经网络的校正方法对内部阻力进行估计。进一步在从端基于估计接触力与定制化的非线性虚拟导纳特性实现自主运动调控功能，在主端基于从端操作力与变阻抗控制实现实时力反馈功能。最终实现接触力从人体、超声探头、机器人从端到医生主端的协同感知与控制，使末端运动方式符合超声诊疗场景下主从控制的操作要求与交互安全性。

基于以上方法设计了一系列实验证明了所提出经食道超声机器人系统的有效性与安全性，其中主从速度控制的标准差为1.79 °/s，主端力反馈标准误差为0.075 N，小于力输出满量程的6%。以上结果表明该研究内容可以潜在推动经食道超声机器人的临床应用，具有一定的实用价值。

Trans-esophageal ultrasound is used for cardiac diagnosis and intervention procedure guidance by operating a trans-esophageal ultrasound probe that enters the human esophagus or stomach from the mouth. Conventional trans-esophageal ultrasound requires doctors to operate the probe manually at close range. This is highly dependent on doctors' clinical experience. In addition, combined imaging with X-rays during cardiac intervention procedures exposes ultrasound doctors to a hostile environment of ionizing radiation, requiring heavy and sultry protective clothing, greatly increasing the work intensity of doctors. The above problems have made it difficult to promote this technology effectively. Therefore, this study deeply explored the system design and teleoperation control method of robotic transesophageal ultrasound to realize effective and safe control through the development of a customized slave robot platform, a master control device, and master-slave teleoperation methods. The specific research content includes:

(1) Multi-degrees of freedom integrated control and hyper-redundant power transmission mechanism design methods of the trans-esophageal ultrasound robot: On the slave side, a compact, lightweight, and modular design is accomplished using a series of customized drive mechanisms coordinated with the control objectives and the integration of electronics. The bi-directional 0.45 Nm operational force sensing function is achieved by integrating two torque sensors into the main structure of the robot. Additionally, by applying the idea of the spline curve based on a fixed point constraint to the design of flexible tube path guidance, effective transmission of the translational power is achieved. Finally, a mobile trolley and a passive tandem arm are used to combine the robot and the tube guide structure to construct a mobile platform.

(2) Four-degrees-of-freedom haptic master device design method with a compact configuration and a small moment of inertia that can rotate around a fixed point: The master device is based on the bevel gear commutation principle to design a new four-degree-of-freedom force feedback double stick structure corresponding to the motion of the robot. The customized haptic function is realized using coreless brushless DC motors, small integrated motor drivers, and the field-oriented control method. The maximum feedback torque on a single axis is 0.086 Nm. By placing the motors on the base platform, the impact of the motor size and weight on the overall performance of the device is avoided. The device has the advantages of a compact structure and a fast response speed.

(3) Contact force feedback and master-slave teleoperation control for continuum robots based on data-driven and bilateral control models: Using a neural network-based calibration method that relies on the probe operating torque and internal resistance of the continuum mechanism, the tip contact force with unknown internal structural parameters of the probe is estimated, and then autonomous motion control is realized by an admittance control method based on the estimated contact force and the customized nonlinear virtual admittance characteristics on the slave side. The real-time haptic feedback is realized on the master side based on the slave’s operating torque and variable impedance control. The collaborative perception and control of the contact force from the human body, ultrasound probe, and slave robot to the master are achieved so that the movement mode of the tip meets the operational and safety requirements of the master-slave control in ultrasound diagnosis and treatment scenarios.

Based on the above methods, a series of experiments have been designed to prove the effectiveness and safety of the proposed trans-esophageal ultrasound robotic system. The standard deviations of the master-slave speed control and force feedback are 1.79 °/s and 0.075N. The standard deviation of force feedback is less than 6% of the full scale of force output. The results show that the research could potentially promote the clinical application of transesophageal ultrasound roboticization and has certain practical value.