| At present,high tibial osteotomy has been used as one of the main surgical methods for the correction of lower extremity deformity,it is of great significance to design an orthopedic external fixation robot which is in line with the characteristics of operation and is intelligently adjusted.In this paper,the surgical requirements and design of proximal tibia orthopedic surgery around genu varus,based on spinor theory and coordinate transformation theory,the mechanism innovation design and analysis of orthopedic external fixator robot are carried out,forming a set of virtual center movement of three directions of rotation and movement along the Z axis.In this paper,the force conduction mechanism of the original Ilizarov bone external fixator was firstly studied.Based on the coordinate transformation theory,the mathematical transformation relationship of the orthodontic force was obtained,and the tibia orthodontic experiment was carried out to measure the changes of each orthodontic force,the force transmission efficiency in the orthodontic process was obtained.On this basis,the simulation model was established and the orthodontic experiment was simulated in the finite element software.The mechanism of mechanical action of Ilizarov bone external fixator was further confirmed,which provided reference for the precise regulation of tibial orthodontic surgery and determined the design requirements.Based on the theory of spinors,a personalized orthopedic external fixation robot was designed.Under the design principle of simple mechanism and convenient adjustment,a personalized adjusting 3R1T-RCM mechanism was proposed to meet the requirements of surgery,it is composed of two parallel modules:2R1T-RCM orthopedic motion mechanism around virtual center,which can realize rotation around X axis and Y axis and independent movement along Z axis;Based on the driving characteristics of gear rotation,a 1R detachable centering rotation mechanism around the Z axis is designed to achieve the function of rotation around the fixed point of the distal ring rotation center.The 3R1T-RCM master mechanism synthesized by parallel modules can be applied to the correction of various complex limb deformations.Finally,the kinematics analysis of the designed 2R1T-RCM mechanism is carried out,the degree of freedom of the mechanism is analyzed,the driving pair of the input is selected,so that the mechanism has a definite motion.By analyzing the inverse position solution of the mechanism,the coordinate relationship between the input pair and the moving platform is given,which lays the foundation for the subsequent prototype control.Then it was imported into the Adams dynamics simulation software to determine the mechanism motion mode,verify the rationality and accuracy of the mechanism motion,analyze the 3D printing prototype,and get the final prototype,which provided the direction for the following optimization design and control of the mechanism. |
PDF Full Text Request