Research On Virtualassembly And Disassembly Teaching System Of Modular Fixture Based On Virtual Reality

With the continuous development and maturity of artificial intelligence,computer simulation and sensing technology,virtual reality technology has further applications in many fields,which involve aerospace,teaching,game development,medical,manufacturing and other fields.In particular,virtual reality technology is widely used in some teaching fields that need to be repeatedly operated,used and maintained at high cost,and it can stimulate students’ interest in learning.At present,the teaching of modular fixture is mainly based on classroom instruction.The teaching form is abstract,single and boring.At the same time,the opportunities for practice are limited and lagging.Students can only understand and perceive the knowledge of modular fixture according to their own imagination,and the teaching effect is not undesirable.Therefore,it is of great practical value to introduce virtual reality technology into the assembly and disassembly training of modular fixture.The purpose of this paper is to develop a virtual assembly and disassembly teaching system of modular fixture based on virtual reality.The paper deeply researches the key technologies of collision detection and assembly sequence planning in the process of disassembly and assembly,designing and implementing the function of the system.The main contents of this paper are as follows:(1)In order to develop an immersive and interactive virtual assembly and disassembly teaching system that is closer to reality,a software and hardware platform based on Unity3 D as the development engine and HTC Vive as the hardware device is constructed to develop the virtual assembly and disassembly system of the modular fixture.(2)Aiming at the problem that Unity3 D collider can not take into consideration at the same time in the aspects of tightness and efficiency,the paper proposes a hybrid collision detection algorithm based on Unity3 D built in Collider and AABB bounding box.This algorithm can replace the inefficient Mesh Collider,making up for the lack of built-in colliders in Unity3 D.Experimental results show that the algorithm is greatly improved in terms of efficiency and compactness,and achieves good collision detection results.(3)Aiming at the combinatorial explosion problem of assembly sequence caused by the excessive number of modular fixture parts,the paper uses the hierarchical cut set method to solve the assembly sequence of modular fixture.The first step is to divide themodular fixture hierarchically,and then use the traditional cut set method to solve the assembly sequence of hierarchy and/or graph and two forked trees,so as to establish the optimal assembly sequence for virtual assembly of modular fixture.(4)Design and implementation of virtual assembly and disassembly teaching system for modular fixture.On the basis of solving the above-mentioned key technologies,the paper designs the virtual disassembly teaching system software,and carries out detailed design of each functional module of the disassembly and assembly system of modular fixture.The contents designs and implements mainly include: human-computer interaction module,three-dimensional model library module,virtual assembly and disassembly training and practice module,assessment module,direction for use modules,et al.Based on the HTC Vive hardware platform installation,the paper tests each functional module of the virtual assembly and disassembly system of modular fixture online.Through examples,the design of the virtual assembly and disassembly teaching system is feasible.