Design Of Adaptive Flexible Finger Based On Gravity Feedback

The flexible fin structure is a passive compliant structure based on the fin ray effect,which can adaptively and flexibly grasp soft objects,and has the advantages of integrated manufacturing,simple structure,low cost,and strong adaptability.The existing common flexible hands are usually made of thermoplastic elastomer(TPE)3D printing,which can adaptively grasp common lightweight objects(within 400g)in life.But every time you grab,the operator must adjust the stroke of the motor according to the material and size of the object to be grabbed.These factors cause the flexible hand to have great limitations in practical applications.At the same time,the production of existing flexible hands usually draws on the experience of the predecessors,and does not have an accurate mathematical model to explain the relationship between its structural parameters and motion characteristics.It has a certain degree of blindness in the process of modeling and manufacturing.Can not find the global optimal solution of the flexible hand structure design.This article focuses on the above two issues to study,establish a mathematical model of common flexible fin-like structures,and design a new type of flexible finger that can "recognize" the quality of the object being grasped and compensate for the grasping of the flexible hand through feedback.Disadvantages of insufficient power.The main research work of this paper around the adaptive flexible finger is as follows:(1)Aiming at the problem of light load capacity of flexible fingers and difficulty in shape adaptation,a flexible finger structure with gravity feedback is designed.First,analyze the deformation principle of the existing flexible fin structure,and abstract the flexible finger model as a beam model.Then through configuration analysis and reasoning,the structure diagram of the flexible finger feedback mechanism is obtained;finally,the key components of the flexible finger and the transmission of the whole machine are introduced.(2)Aiming at the problem of large plane deformation of the flexible fin-like structure during the stress process,a theoretical model of a flat full-flex finger and a partially flexible finger based on the three-beam model is proposed.First introduced the single beam chain beam restraint model(CBCM);then through the calculation of the single beam CBCM model,joint balance equation,rotation equation and boundary conditions,the analytical solution of the three beam model was obtained;finally,the three beam model was analyzed Analyze the model,the overall boundary conditions,the rotation equation and the force balance equation at the end point,and obtain the mathematical model of the flat full-flex finger and part of the flexible finger;(3)Solve the mathematical model in MATLAB,compare the results obtained with ANSYS simulation results and physical deformation results respectively to verify the correctness of the theoretical model;(4)Build an experimental platform,use 3D printing technology to make and assemble a real object of a flexible finger with gravity feedback,and conduct experiments.First select the appropriate control and drive mode;then compare the flexible fingers with gravity feedback designed in this paper and ordinary fingers in three aspects: adaptability,maximum grasping force and gain effect.