Research And Experimental Verification Of Personalized External Braces Generation Algorithm Based On STL Files

Fracture patients generally need external fixation for adjuvant treatment.The commonly used external fixation methods include splint fixation,plaster fixation and brace fixation.Splint fixation is easy to appear loose,and if banded too tight it may cause compression injury.Plaster is airtight,heavy,smells bad,and hard to dismantle,which makes the patient uncomfortable.External fixation brace’s type is usually several fixed kinds while each patient has different limbs sizes,so the braces may not fit or match well with the patient’s limbs.Therefore,the personalized external fixation which is breathable,light,comfortable to wear and has good fixation effect is needed,and research and develop the personalized external fixation making system is an urgent need for the fracture treatment.Personalized external fixation making system is made up by 3D scanning,brace modeling and 3D printing.3D scanning obtains the external contour data of the affected limb.The brace modeling part generates an external fixture based on the external contour data of the affected limb.The 3D printing part prints the external fixture.Because it is tailored according to the size of the limb,the brace can perfectly match the appearance of the affected limb and provide a firm and comfortable fixation function.How to generate a wearable,beautiful,breathable,fixed well personalized external fixation model is the key of the system.In this thesis,I present an algorithm for generating personalized external fixation based on STL files,which can generate a wearable external fixation model according to the 3D scanning STL files of the limb.STL file is a kind of 3D data format,which is a standard file in reverse engineering field and is widely used in data storage,transmission and other aspects.STL files use small triangular patches to approach real 3D objects.Edit STL files means edit small triangles.The personalized external fixation model can be generated by forming coat,hollowing pattern,deforming and designing snap-fit structure on the STL files.Through the research and experiment of deleting and adding triangular patches,cutting,offsetting,triangulating,hollowing,deforming and other editing algorithms on the simple STL files,the feasibility of each independent algorithm was verified.Combining these algorithms,an ideal wrist STL files model with a small amount of data was simulated.An external fixed brace model was generated outside the model,so the feasibility of the whole algorithm was illustrated.On this basis,combined with 3D scanning and 3D printing,the feasibility of the whole system was verified.Firstly,grating projection combined with binocular stereo imaging was used to acquire the wrist surface data of multiple angles.Secondly the data was spliced into a complete wrist point cloud files.Transformed it into STL files,and after the outer sleeve generating,hollowing pattern,designing snap-fit structure,a wearable external fixed brace model was generated.After 3D printing,it could be worn on the wrist,which had good matching with wrist as well as good fixation effect,and was light,breathable,and beautiful.Thus,verified the feasibility of the proposed technical scheme.