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The Internet of Things (IoT) concept describes an intelligent connectivity of smart devices using the internet network. Nowadays, companies try different approaches for predictive maintenance as a solution to reduce costs and the frequency of maintenance activities. The IoT platforms provide a good support for predictive maintenance as it can integrate information from different machines and manufacturing systems. The main drawback in integrating production system with IoT dedicated platforms is the communication framework, knowing that the main industrial communication protocols are incompatible with modern communication protocols implemented on IoT platforms. In this context, the present paper proposes a new and simple method for on-line monitoring and predictive maintenance of industrial equipment. This method has two features of connected manufacturing. One of these is process monitoring for constant quality assurance, the other one is condition monitoring in order to prevent unplanned downtimes. A case study is presented to demonstrate the feasibility of the proposed method.

The sense of touch is an important means of communicating and exchanging information primarily between people and between people and the environment, from the very first years of life. Nowadays, researches and technology advances in different domains make use of touch, man-computer communication and interaction throughout immersive simulation environments being also facilitated and enhanced by the kinesthetic technology. The importance of haptic feedback for different applications is already a proved fact. However, it is still underrepresented in the everyday computer interfaces, mainly due to a current unfavourable compromise between price and user’s experience quality. That is, even if many haptic devices are available, they are either prohibitive in term of price, if provide high quality, or they are inexpensive and offer low realism haptic effects. Currently, there is no real intermediate device, and no device that can provide hardware upgrade according to users’ needs. In this context, this paper provides an analysis of existing haptic equipment, both prototypes and commercially available devices, and presents different approaches used in haptic-based scenarios. On this basis, a critical set of requirements for a new type of haptic device are inferred. It could represent an innovative and affordable solution for a larger range of potential users: engineers, physicists, trainers, designers, researchers, as well as hobbyists.

The impact of the disassembly process on the design of a product is a recognized fact, influencing recycling, maintenance, repair, and component/material re-using—essential aspects for a sustainable development. For simplifying and improving their work, as well as for designing proper and efficient disassembly plans, it is important for engineers to benefit from a disassembly method, for automatically generating dismounting sequences, incorporated in a software solution for providing rapid disassembly information that can be further used for real-time immersive simulations. The disassembly method proposed in this paper is based on two innovative elements: the connection interface concept and the mobility operator that integrates information on geometrical constraints, contact surface relative position and common area, neighboring components, and relative mobilities of the assembly components. All these data are corroborated with knowledge-based criteria and are used to generate a set of connection interfaces for a product to define mechanical joints, automating the identification of fasteners in the assembly and determining the components’ mobility within assembly. As a consequence, it is possible to calculate and realistically simulate components’ disassembly paths. In the proposed method, valid disassembly trajectories of a component relative to its surrounding ones are modeled based on the mobility operator, the swept volume approach is used to evaluate collisions between components, and finally, the disassembly sequences are determined through an improved layer peeling technique.

Enrolling in the current trends of using collaborative virtual environments and virtual reality techniques for engineering applications, the current paper presents the synthetic results of a research in which an innovative method and software application were developed for analyzing and simulating the Assembly/Disassembly (A/D) operations of mechanical products. Starting from the 3D CAD model of an assembly and using connection interface and mobility operator concepts, the application supports the designers in generating valid A/D plans by determining the interfaces between components, calculating the components mobility and identifying the functional role of components in an assembly. Thus, the developed software provides designers an automated tool for analyzing A/D operations, obtaining and simulating A/D sequences, useful in the design phase of a mechanical product, for training the operators, as well as for improving the productivity of activities such as recycling, maintenance and reusing. Moreover, the application was conceived so that, in a further step, to be integrated in an immersive environment, offering a realistic simulation in two modes of interaction: free mode and kinematically guided. Finally, in order to validate the proposed methods and concepts, the application was tested for evaluating users’ satisfaction degree.

PurposeThe paper aims to present the processing pipeline of an assembly immersive simulation application which can manage the interaction between the virtual scene and user using stereoscopic display and haptic devices. A new set of elements are integrated in a Collaborative Virtual Environment (CVE) and validated using an approach based on subjective and objective users’ performance criteria. The developed application is intended for Assembly/Disassembly (A/D) analysis, planning and training.Design/methodology/approachA mobility module based on contact information is used to handle the assembly components’ movements through real-time management of collision detection and kinematically constraint guidance. Information on CVE architecture, modules and application configuration process are presented. Impact of device type (3 degrees of freedom (DoFs) vs 6 DoFs) over user’s experience is evaluated. Parameters (number of assembled components and components assembly time) are measured for each user and each haptic device, and results are compared and discussed.FindingsTest results proved the efficiency of using a mobility module based on predefined kinematic constraints for reducing the complexity of collision detection algorithms in real-time assembly haptic simulations. Also, experiments showed that, generally, users performed better with 3 DoFs haptic device compared to 6 DoFs haptic equipment.Originality/valueThe proposed immersive application automates the kinematical joints inference from 3D computer-aided design (CAD) assembly models and integrates it within a haptic-based virtual environment, for increasing the efficiency of A/D process simulations.

Nowadays the use of Virtual Reality (VR) based surgical simulators or training environments is becoming more and more spread in the medical world. These are usually dedicated to the development and improvement of novice trainees’ skills by helping them to learn different surgical techniques, to use proper instrumentation or to practice surgical protocols, but also in the training of expert surgeons for conserving their skills, for planning or rehearsing new, complicated or rare procedures. In this general context of interest, our paper aims at answering the following questions: What are the main requirements for a haptic device in order to be successfully used in the virtual training of orthopedic surgeons What requirements are mandatory to be included in an orthopedic surgery haptic-based training application for providing a realistic user’s experience These are legitimate questions considering that surgical education can really benefit the advantages offered by such virtual simulators only if they can satisfy a list of requirements among which high level of immersion and interactivity, realistic 3D virtual models and constraints of anatomical structures, good correspondence between real and simulated cases (i.e. a natural ‘behavior’ and ‘feeling’ of simulated anatomy). The focus of the literature review presented in this paper will be on orthopedic VR simulators for drilling, sawing and fixing implants screws, pins and plates, with an emphasize on devices’ characteristics and applications features. This study enrolls in the trend of improving user’s immersion experience at a cost as low as possible, representing the basis on which an innovative and affordable haptic device and an application for training basic orthopedic surgical skills are proposed for development in further research.

The paper presents the development of a new software tool integrated with SolidWorks CAD system for generating feasible disassembly directions based on the concept of mobility operator. In generating the disassembly path of a component, our approach considers that two steps should be undertaken: first, the interface between components is broken and then the component is extracted from the assembly by translating it along a collision free removal path. Different data from the CAD model of the assembly is automatically detected, such as: geometrical constraints, contact surfaces relative position, common area, components neighbours, etc. Based on this information, a general mobility operator is deployed, which is further used to evaluate the families of trajectories associated to the contacts between different components of a mechanical system. Thus, the developed mobility operator mathematically expresses all possible movements between assembly components (rotations, translations and helical movements), and it can be used for a real time graphical representation of components mobilities, mandatory aspects in developing a virtual environment for simulating the Assembly/Disassembly (A/D) tasks as part of an efficient Product Design Process (PDP).

Assembly/disassembly (A/D) simulations are important to improve designs and efficiency of product development processes. In order to get efficient simulation processes it is important to simulate all the possible relative movements between the components in a mechanical system (assembly). This is important both in the context of interactive simulation and in the context of immersive/real time simulations. If some categories of movements are missing, simulations can loose key configurations, hence they may be no longer meaningful. This paper deals with a theoretical framework for developing of a kinematical model able to represent all the valid relative movements of a reference component with respect to its surrounding ones, which form a family of trajectories. It is based on the analysis of the three basic movements: translation, rotation and helical movements. In order to determine the compatibility between different families of trajectories, a bi-quaternion is associated to each contact area between the different components. All possible trajectories for each component are analyzed, for the three basic type of movements, in order to find the compatible ones, which leads to the specification of an operator. Thus, the results of all the possible associations are determined and a general combination operator is proposed and its properties are demonstrated. This operator can form, in a real time simulation environment, the basis for determining at each moment, the valid movements between components, thus reducing the complexity of collision detection algorithms.

A new application for virtually simulating assembly tasks was developed by integrating multimodal data and kinematic information provided by a mobility module into a Collaborative Virtual Environment. During assembly simulations, the haptic device implemented in the application supports the user’s movements by using the automatically detected kinematic constraints between the components of the assembly. Thus, all stages of the assembly process can be simulated, which leads to an increase of the user immersion. The current paper presents the methodology, the protocols and the results of evaluating the application, the test being performed by a group of 20 participants. Tasks were run for assessing the following criteria: usability, efficiency, ease of use and quality of the haptic feedback. Each participant tested the application for two types of assemblies (mounting flange and standard vise) with different complexity and number of components. Testing protocols considered both objective evaluation (using real-time information), as well as subjective evaluation using questionnaires. The analysis of the results proved the feasibility of the proposed approach. Further work will be focused on extensive studies for assessing intra-users variations and improvement of the haptic feedback for a number of particular situations reported by users as important.

Programming languages have benefited from increased attention lately. With corporations like Google, Facebook and Mozilla investing in language design, there is a lot of activity in the mainstream languages domain. State of the art features like advanced type systems that were only available to more research-centered languages such as Haskell, are now making their way into the mainstream through languages like Rust. Rust is an up-and-coming system programming language that aims to fill the same role as C and C++, but in a much safer way. To achieve this, it brings a rich type system, alongside a pragmatic implementation of region based memory management, a feature that allows safe memory handling without the need of a garbage collector. Aiming for the mainstream, Rust comes with tooling to aid developers in their work. One such tool is Rustdoc, a program that automatically generates documentation based on type information and programmer comments. We aim to enhance Rustdoc to provide more advanced search support through features that are impossible to implement for dynamic languages, and even static languages with less advanced type systems, like C and Go.