Today, manufacturing industries are trying to improve their competitiveness by combining manufacturing per se with information technology Virtual reality is being used in product development processes in manufacturing enterprises as a helpful technology to achieve rapid consolidation of information and decision-making through visualization and experience In this article, 154 articles relevant to virtual reality’s application to manufacturing were surveyed and analyzed For this, (1) an analysis map was created, based on a virtual reality technology classification and the new product development process; (2) the articles investigated were located on the map; and (3) bibliometric analyses were carried out Trends in past and present research were examined and future virtual reality research directions and application plans for manufacturing enterprises are discussed

Virtual reality applications in manufacturing industries: Past research, present findings, and future directions:

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Future directions for the development of virtual reality within an automotive manufacturer.

Empowering and engaging industrial workers with Operator 4.0 solutions

This paper presents a highly interactive and immersive Virtual Reality Training System (VRTS) (“beWare of the Robot”) in terms of a serious game that simulates in real-time the cooperation between industrial robotic manipulators and humans, executing simple manufacturing tasks. The scenario presented refers to collaborative handling in tape-laying for building aerospace composite parts. The tools, models and techniques developed and used to build the “beWare of the Robot” application are described. System setup and configuration are presented in detail, as well as user tracking and navigation issues. Special emphasis is given to the interaction techniques used to facilitate implementation of virtual human–robot (HR) collaboration. Safety issues, such as contacts and collisions are mainly tackled through “emergencies”, i.e. warning signals in terms of visual stimuli and sound alarms. Mental safety is of utmost priority and the user is provided augmented situational awareness and enhanced perception of the robot’s motion due to immersion and real-time interaction offered by the VRTS as well as by special warning stimuli. The short-term goal of the research was to investigate users’ enhanced experience and behaviour inside the virtual world while cooperating with the robot and positive pertinent preliminary findings are presented and briefly discussed. In the longer term, the system can be used to investigate acceptability of H–R collaboration and, ultimately, serve as a platform for programming collaborative H–R manufacturing cells.

Design of a virtual reality training system for human–robot collaboration in manufacturing tasks

High precision products (HPPs) with multidisciplinary coupling are widely used in aerospace, marine, chemical and other fields. Since the internal structure of HPPs is complex and compact, the assembly process requires high precision and involves multidisciplinary coupling. Traditional assembly process of HPPs is based on manual experience, which results in low assembly efficiency and poor-quality consistency. Given the above problems, this research proposes a digital twin-driven assembly-commissioning approach for HPPs. Firstly, this paper introduces the theoretical framework of digital twin-driven assembly-commissioning. Secondly, we introduce the construction method of assembly-commissioning total factor information model based on digital twin technology; the fusion method of twin data and the interoperability method between digital twin models; in addition, the assembliability prediction and assembly-commissioning process optimization methods. Finally, a case study product is used to verify the effectiveness and feasibility of the proposed method.

A digital twin-driven approach for the assembly-commissioning of high precision products

Assembly constraint is an important factor for product assembly. Constraint is not only necessary for accurate locating of parts but also an important way to realize assembly operation process in virtual assembly (VA) system. In this study, to realize VA reasonably, uniform representations of assembly constraint, equivalent relation between constraint and degree of freedom (DOF), and movable DOF reduction are defined. Several algorithms including based-constraint assembly relation recognition, assembly parts location solving under free and constrained spaces, and movement navigation are developed. These algorithms have been applied to integration virtual assembly environment (IVAE) software system. An example is illustrated, and the results prove that the algorithms provide a good support for the constraint treatments in IVAE and the high consistence between virtual and real assembly process is realized.

Virtual assembly technologies based on constraint and DOF analysis

Real operators are the initiators in assembly and disassembly activities. They participate throughout the whole process. In this sense, as an avatar of a real operator, virtual human (VH) plays an important role in virtual assembly and maintenance simulations. After detailed analysis of interactive assembly and disassembly process, the function requirements for VH are defined. Based on the defined requirements, the following works are done. First, a real-time driving model is established with a dynamic constraint applied to support personalized human model driving. Then, a driving error model is proposed for quantitatively analysis of VH’s driving error coming from the motion capture system. After that, on the basis of constraint processing method, an interactive operation modeling method for VH is presented. This method deals with interactive operation modeling in scenarios where VH manipulates the product directly, VH manipulates tools, and VH manipulates the product using tools. Finally, an assembly simulation for automobile engine connecting rod caps is implemented and a user survey is carried out. The survey result demonstrates the feasibility and validity of the proposed model and method.

Virtual human modeling for interactive assembly and disassembly operation in virtual reality environment

As complex products such as automobiles and ships are usually developed at geographically dispersed locations, it brings the difficulty for component model verification and assembly process evaluation. To cope with this challenge, a relatively comprehensive system scheme which supports complex product real-time collaborative interactive assembly is proposed. To get high performance, the technologies such as parallel rendering for complex scene based on pc-cluster, high-efficient collision detection method, the mechanism of event synchronization based on HLA/RTI (High level Architecture/Run-time Infrastructure) are applied. A prototype system named Distributed Parallel Virtual Assembly Environment (DPVAE) is developed. With DPVAE, users at different location can do assembly operation collaboratively by hand or by tool, to conduct the component model verification and assembly process evaluation at the same time. Through a case study of RA750 car assembly, the validity of system functions has been demonstrated successfully.

A virtual environment for complex products collaborative assembly operation simulation

To improve virtual human motion simulation and generation efficiency in virtual assembly and maintenance (AM in this way, the PM can be quickly generated. As for FM and TM generation, their semantic-level parameterized models including engineering attributes are created; then, their generation processes are represented; in the generation processes, a virtual human posture automatic reasoning model is established to support auto-generating A&M motion. The approaches in the present study are validated by generating virtual human motions in partial assembly process of auto engine. Res...

Virtual human hybrid control in virtual assembly and maintenance simulation

Complex pipe layout plays an important role in ship building. Pipes prefabricating and assembling often depends on testing and rebuilding in outfitting. This leads to more workload, high cost and longer manufacturing cycles. In this paper, a new virtual assembly system called Integrated Virtual Assembly Environment (IVAE) is introduced, in which the ship outfitting can be simulated and process planning can be completed. With the help of assembly constraints management, collision detection and response, assembly sequence and paths planning, users can assemble the parts interactively in a virtual outfitting environment, just as in an actual cabin. As well as for virtual ship outfitting, IVAE can also be used in general product development. As a typical case, the pipe layout in the engine room of a 5000 M3 hydraulic dredge from Hudong-Zhonghua Shipbuilding (Group) Co., Ltd is given to test virtual ship outfitting in IVAE.

Dianliang Wu

Papers

Virtual assembly technologies based on constraint and DOF analysis

Virtual human modeling for interactive assembly and disassembly operation in virtual reality environment

A virtual environment for complex products collaborative assembly operation simulation

Virtual human hybrid control in virtual assembly and maintenance simulation

Integrated Virtual Assembly Environment and its application in ship piping layout