Research On The Kinematics And Workspace Of A New Minimally Invasive Abdominal Surgery Robot

The new medical model,Bio-Psychosocial Medicine Model,continues to develop and gradually influences our diagnosis and treatment of diseases.The "Scarless technology" caters to the development needs of the new medical models and has become a hot spot of research.The mutual interference between the surgical instruments of the traditional single-port multi-channel surgery at the incision will reduce the flexibility of the operation and cannot complete the fine surgical operation,however,the trans-umbilical single-port laparoscopic surgery can achieve no scar on the abdominal body surface,which become more and more popular among patients.Therefore,this article mainly researches on the workspace of the new minimally invasive abdominal surgery robot system for the single-incision laparoscopic surgery.The design requirements of the new minimally invasive abdominal surgery robot system are analyzed.Then,on this basis,the working principle and the basic surgical operation flow of a novel minimally invasive abdominal surgery robot system are elaborated and analyzed.According to the characteristics of the single-hole minimally invasive technique and the 1:2 folding ratios required by the system design,the structural dimension of the system's miniature Stewart platform,articulating arm,annular platform,end surgical instruments,and visualization unit are determined and analyzed.Through using the UG software to model the annular platform and analyze the kinematics of the annular platform on the unfolding and contraction during the movement of the surgical instruments.The curve of displacement,velocity and acceleration of the motion corresponding points can be obtained.Different medical metal materials are selected as the research object to do the static analysis of the single bar by using the COMSOL software.As a result,the more suitable material is chosen through the comparison and the analysis the selected materials.It aims to establish a platform model based on the design structural dimension of the miniature Stewart platform.The forward and inverse solutions of the platform mechanism are deduced by the Newton iteration method and the closed-loop vector analysis method,and then the influencing factors as well as constraint discriminant methods of the workspace of the platform mechanism are systematically analyzed.Combining step-by-step search method and dichotomy method,the flow chart of solving the working space was worked out,and the MATLAB software was used to solve the workspace and draw the image.To draw the main factors that limit the workspace the change curve of the size of the workspace is analyzed.According to the kinematics analysis of the annular platform and the miniature Stewart platform,combined with the parameters of the target workspace,the target workspace of the new abdominal surgery robot system is generated.Basing on the establishment of a minimally invasive abdominal surgery model and comparison the workspace required for simple abdominal surgery with the new type of surgical robot,the research verifies the feasibility of the new minimally invasive surgical robot in the single-incision laparoscopic surgery and provides a reference in natural orifice transluminal endoscopic surgery in the future.