Research On Full-automatic Robot Ultrasound Autonomous Scan And Three-dimensional Imaging System

As a real-time,convenient and non-radioactive medical imaging method,ultrasound has been widely used in clinical practice.But higher user differences are still the main challenges it faces.The experience and techniques of different ultrasound doctors vary from person to person,so compared to other medical imaging methods,the standardization of ultrasound scanning is difficult to solve.On the other hand,current ultrasound doctors have a heavy task,and long-term scanning with a handheld probe may cause damage to their bones,joints,muscles,and even affect their normal work and life.In addition,the traditional two-dimensional ultrasound cannot obtain the three-dimensional anatomy information of the tissue,and compared with the three-dimensional ultrasound,it cannot provide the doctor with an intuitive and clear diagnostic field of vision.The current three-dimensional volumetric probe,which is commonly used in clinical three-dimensional ultrasound imaging,not only has a narrow imaging field and relatively poor imaging quality,but can only be applied to the scanning of some specific parts.At present,with the development of science and technology,robot technology has gradually integrated into people’s lives,especially in applications that are combined with the medical field,it has more outstanding performance.The robot system has the characteristics of high precision and repeatability.When combined with clinical ultrasound,it can effectively reduce user differences and standardize the scanning process.In addition,the real-time positioning function of the robot system can also be used to achieve three-dimensional ultrasound volume reconstruction under free two-dimensional ultrasound scanning.This shows that the emergence of a medical ultrasound robot system has brought a new way to solve clinical ultrasound problems.Based on this,this research has developed a set of fully automated robotic ultrasound autonomous scanning and 3D imaging systems.It is a complete ultrasound-assisted diagnostic system that integrates multiple functions such as full-automatic multi-angle scanning,real-time force feedback control,real-time ultrasound quality optimization,and three-dimensional imaging.It is mainly composed of three modules: automatic vision guidance,automatic scan control,and automatic three-dimensional imaging.In the automatic vision guidance part,a Microsoft Kinect V2 depth camera is used to obtain the scanning scene information,and then the point cloud information of the patient’s skin area to be scanned is automatically segmented,and the scanning path is automatically planned accordingly.This path includes all the information to determine the posture of the end effector of the robotic arm,so that it can complete the scan in a real-time and controllable manner,so as to realize the task of the probe completely scanning the entire target area.In the automatic scan control section,the system uses a KUKA iiwa 7-type robotic arm to drive the probe.In order to ensure the safety and reliability of the robotic arm,force protection measures combined with impedance control are used to perform the basic movements of the robotic arm,giving the robotic arm a "soft" characteristic and also making it have a constant and safe scanning force.At the same time,in order to optimize the quality of the collected ultrasound images,a servo control based on ultrasound image quality optimization is added to this base to adjust the probe attitude in real time to obtain high-quality ultrasound images,which enables the system to perform better scanning on complex surfaces.In the automatic three-dimensional imaging part,the system collects real-time ultrasound images and their corresponding poses during the scanning process,and uses a pixel-based spherical kernel function interpolation algorithm to perform threedimensional ultrasound volume reconstruction to obtain an intuitive three-dimensional tissue image.Finally,this study verified the feasibility of each functional module of the system by scanning and reconstructing experiments on phantoms and human bodies.In addition,several error evaluation experiments are designed to test the accuracy of the system.Experiments show that the system can complete scanning and reconstruction tasks safely and efficiently.The scanning error of the system is about 1-3mm,the length error of 3D ultrasound reconstruction is about 0.35%,and the volume error is about 1.1%.This shows that the system can better help doctors complete the scanning of 2D ultrasound and the acquisition of 3D ultrasound,and it is expected to be used in the clinic in the future.