Research On Three Dimensional Mathematical Model And Bending Algorithm Of Orthodontic Archwire

With the continuous development of living standard of the people,which result people put forward higher requirement for health and beauty.Healthy teeth can not only make a person deep and good impression,furthermore can improve the ability to chew food,maintain the health of the digestive system.Currently,most of orthodontic archwire is bended by hand with doctor’s experience.Low efficiency,big labor intensity and low accuracy are its main shortcomings,while the use of robot to replace the doctor finish boring archwire bending will be great help to improve the efficiency and accuracy.In this paper,based on the clinical actual demand and the oral cavity teeth and jaw structure,three dimensional mathematic modeling method of orthodontic archwire is built,and combine with the structure characteristics of orthodontic archwire bending robot,in order to improve the accuracy and efficiency of bending,the algorithm of bending the archwire is researched.The orthodontic archwire three dimensional mathematical modeling method is established.Based on the structure of the relationship between orthodontic bracket and the archwire,in order to determine key parameters for model building,tooth marks and dental arch curve are built;by comparing structures methods and characteristics of several common curve,orthodontic archwire model of mathematical expression and the selection of control points based on the space of the Bezier curve is built;with the help of MATLAB developed tooth curve generation system based on the Bezier curve,three dimensional mathematical modeling simulation and verification are processed.Orthodontic archwire bending algorithm is established.Bending orthodontic archwire process by hand as the theoretical basis,and orthodontic archwirebending robot motion and bending mode is analyzed,and selection of archwire forming method for bending algorithm,control node and its curve angle of curved shape on the planning method were established.The orthodontic archwire bending robot control system is proposed.Through the analysis and comparison of several common software development tools,the orthodontic archwire bending robot upper system based on PMAC card is realized in Lab VIEW,through Ethernet front-end ports to PMAC multi-axis motion control to send commands to complete the specified orthodontic archwire bending action and other tasks.Take one the patient’s oral cavity parameters,for example,using the domestic stainless steel square in the development of archwire bending experiments robot control system to finish archwire bending experiments;by measuring and comparing the obtained experimental results with the ideal data,the error sources is analyzed,and put forward the solution to lower the error.In this article,through theoretical and experimental research on three dimensional mathematical model and algorithm of orthodontic archwire bending,a scientific basis for establishing three dimensional archwire model rapidly and accurately is proposed.Through the development of control system,robot can complete the archwire bending tasks accurately and efficiency,greatly improves the quality of forming the archwire,reduces the doctor’s labor intensity,and promotes the development in the field of orthodontics,benefit for patients.