Precise manipulation approach to facilitate interactive modular fixture assembly design in a virtual environment

PurposeThe virtual design environment offers users an opportunity to interact with a virtual prototyping rather than physical models and to build a fixture configuration in a realistic way. But the virtual reality (VR) environment tends to be inaccurate because humans have difficulty in performing precise positioning tasks. Therefore, it is necessary to implement precise object manipulation methods for assembly and disassembly activities, so that users can perform modular fixture configuration design efficiently in VE. The purpose of this paper is to develop a VR‐based modular fixture assembly design system, which supports the design and assembly of modular fixture configuration in a virtual environment.Design/methodology/approachGeometric constraint‐based method is utilized to represent and treat the assembly relationship between modular fixture elements. The paper presents a hybrid method of rule‐based reasoning and fuzzy comprehensive judgment to capture the user's operation intent and recognize geometric constraint. Through degrees of freedom based analysis, a mathematical matrix is presented for representing and reducing allowable motion of fixture elements, and a constraint‐based motion navigation approach is proposed to ensure that the manipulation of a fixture component not violate that the existing constraints.FindingsThe paper finds that the proposed techniques are applicable to the convenient manipulation and accurate positioning of fixture elements in a virtual environment.Practical implicationsComponent manipulation plays a key role in interactive virtual assembly design. The proposed approach in this paper enables interactive assembly design of modular fixture in virtual environment.Originality/valueThis paper presents a geometric constraint‐based approach that realizes automatic assembly relationship recognition, constraint solving and motion navigation for interactive modular fixture assembly design in a virtual environment.