Virtual Reality Training System for CTS Design and Simulation

Over the last years, with the rapid development of 3D Web technologies, such as Web3D, HTML5 and WebGL, have allowed complex 3D scenes to be rendered interactively, within a web browser. Compared to the traditional virtual training system, the traing system with WebGL, which requires no explicit installation plug-in and is able to achieve cross-platform easily, is getting more and more popular. This foundation has made it possible to build powerful the virtual acupuncture training system. However, designing and implementing a complete virtual training system using WebGL is not straightforward and complex. In this paper, the author presents a virtual acupuncture training system that using WebGL and Three.js 3D Engine. It can be used to learn acupuncture, and also give ordinary people a reference. Our experiment result shows that WebGL and Three.js 3D Engine can easily support the virtual acupuncture training system, and have a good response. By using this system, the trainers can be more familiar with the acupoint of the human body. At the same time, the trainer will improve his ability in acupuncture therapy. We also hope to provide some references for the development of the virtual training system.

The availability of consumer-facing virtual reality (VR) headsets makes virtual training an attractive alternative to expensive traditional training. Recent works showed that virtually trained workers perform bimanual assembly tasks equally well as ones trained with traditional methods. This paper presents a study that investigated how levels of immersion affect learning transfer between virtual and physical bimanual gearbox assembly tasks. The study used a with-in subject design and examined three different virtual training systems i.e., VR training with direct 3D inputs (HTC VIVE Pro), VR training without 3D inputs (Google Cardboard), and passive video-based training. 23 participants were recruited. The training effectiveness was measured by participant’s performance of assembling 3D-printed copies of the gearboxes in two different timings: immediately after and 2 weeks after the training. The result showed that participants preferred immersive VR training. Surprisingly, despite being less favourable, the subjects’ performance of video-based training were similar to training on HTC VIVE Pro. However, video training led to a significant performance decrease in the retention test session 2 weeks after the training.

The sense of touch is essential to perform discriminating tasks in virtual reality applications or virtual training systems. To discriminate between different virtual objects, a human operator needs to clearly perceive the stiffness of each object. Stiffness is not only a material property, but also a characteristic of the particular object and express how it is being touched. Stiffness affects the perception of surface topography and depends on the area of applied force. While haptic-enabled virtual reality training systems have been received considerable attention in recent years, our main criticism on these systems is that their virtual environments provide homogeneous haptic stiffness and less perceptually accurate virtual space. This paper investigated how texture affects the perception of haptic stiffness of the virtual object. By performing a psychophysical experiment, we determined that human operator' average accuracy in discriminating perceived haptic stiffness of the virtual object is depending on its texture information and spatial variations. Our findings underscore the importance of implementing spatially varying haptic parameters.

This paper presents a virtual reality training system for the lower limb rehabilitation robot, which can simulate the bike riding and encourage patients to join in the recovery training through the built-in competitive game. The virtual reality training is a variable speed active training under the constraint trajectory, and it has adapting training posture function which can provide individual riding training track according to the legs length of patients. The movement synchronization between the robot and virtual model is achieved by interaction control strategy, and robot can change the training velocity based on the signal from feedback terrains in game. A serious game about bike match in forest was designed, and the user can select the training level as well as change perspective through the user interface. The training can be paused at any time, and the timer function could reflect the recovery of patient.

Due to the recent enriched micro-level hardware and advanced computer software technology, portable yet powerful smart devices draw fervent responses from users and consequently the world’s smart device market has been rapidly expanded. In addition, since smart devices can be used anytime and anywhere using the wireless internet environment, the traditional PC-oriented works are swiftly moving to smart devices. Recently, the demands for representing more realistic 3D deformable objects have been increased for smart device based 3D game, virtual reality, 3D mobile advertisement, augmented reality and so on. However, current smart devices cannot sufficiently process the details of complex 3D object representation and associated physics based animation yet. This paper proposes a new optimized 3D object simulation and collision handling method specifically targeted for smart devices. The proposed hierarchical bounding sphere FFD- AABB (Free Form Deformation -- Axis Aligned Bounding Box) algorithm provides efficient 3D object simulation, since it quickly rejects unnecessary complex collision tasks by executing simple hierarchical bounding sphere distance tests. We have conducted experimental tests under various iOS environments and have performed comparative performance analysis with previous methods. The proposed method shows on average 34% improvement in dynamic simulation and collision handling procedures.

We present an algorithm for collision detection between multiple deformable objects translating in a large environment. We use Spatial Partitioning to subdivide the scene and a Bounding Volume Hierarchy to decompose the objects, using octrees in both cases. The algorithm is divided in two parts, the Broad and Narrow Phases, with objects that can be rigid or deformable. In the Broad Phase, an octree is used to partition the scene and cull away the object’s Bounding Volumes that are distant. In the Narrow Phase, a hierarchical decomposition of Axis Aligned Bounding Boxes or spheres is employed to reduce the number of primitives in the pairwise comparisons. In summary this work is a general-purpose collision detection technique for performing real time collision detection of deformable bodies in interactive 3D applications.

Virtual training is a growing mode of operation within high technology enterprises through virtual technology and virtual operating strategy. The purpose of this paper was to develop a new conceptual framework and propositions to assist understanding of a new training ideology. The approach used was the integration of related literatures and development of arguments for main factors in virtual training system. We argue that basic technology, management theory and system structure are the key factors for constituting virtual training system in high technology companies. Virtual training system application includes knowledge management system, virtual learning society and autonomic training.

As the development of the Virtual Reality (VR) technology, the demands of the virtual training system has been extended from traditional visual requirements to tactile requirements. For this trend, this paper carried out a study on the virtual training system based on force feedback data glove. Firstly, an integrated data glove with functions of spatial positioning, action capture, and force feedback was designed to accomplish the tactile interaction between the user and the system. Then, a data interface adapter and a 3D virtual demonstration scene were developed to process and display the data information of the training operations. Applications of this system show that the system framework is reasonable and feasible, and the training effectiveness is remarkable.

An algorithm of two stages collision detection is presented for moving objectives in virtual scene. Firstly, AABB bounding box was used to test the intersection of interesting objects in coarse detection stage. Then combining space projection with Z-buffer algorithm, the potential intersecting objects in previous step were tested in precision detection stage, thus we can obtain objects collision data information and complete object collision detection. Finally experimental results show that the algorithm is more efficiency than traditional bounding box detection, the improved technology can realize further accurate collision detection.

The virtual training system involves a large number of technical problems which affect the promotion and application in our country. In this work, several key techniques for the development of engineering equipment virtual training system are addressed. Firstly, the reconstruction method for three views of machine parts is proposed based on rapid 3D surface fitting as well as NURBS composite surface. Then, the interactive control techniques for the 3D visualization interactive assembly are studied in detail. The key technology of collision detection is also illuminated in the last part. The entire engineering equipment support training system, that includes structure expressing, principle demonstration, panoramic roaming, disassembly training as well as maintenance and repair training, is developed. This facilitates the trainees in learning the support training procedures step by step, and quickly improves their technical skills. DOI: http://dx.doi.org/10.11591/telkomnika.v11i2.2052

Immersive learning system for manufacturing industries

We present a hybrid approach to generate plausible motions for high-DOF human-like articulated figures in constrained environment with multiple obstacles. The method combines motion planning and motion blending techniques to efficiently produce natural and collision-free human motion for different tasks.

In view of the shortage of traditional construction safety education in China, this paper introduces virtual reality technology into the field of safety education. The virtual reality construction safety training system designed allows multiple experiencers to be physically, visually and tactfully present at the same time. In the virtual scene of construction accident safety hazard, the experiencer completes the consciousness migration that corresponds the virtual scene to the real scene, thereby avoiding the safety accident in the real construction and maximizing the safety education effect. The overall architecture of this work includes the virtual reality system and the vibration system. The scene model in the virtual reality system is mainly 3D modeling with 3Dmax, and the Unity game engine is used for animation and interaction design. Because the system is mainly for traffic construction and construction units, the design scene mainly includes three major parts: bridge construction scene, road construction scene and tunnel construction scene. The vibrating system is designed to enhance the virtual experience. The system communicates with the host to acquire the corresponding vibration signal and drive six low-frequency vibrating horns, so that the experiencer have a strong sense of vibration.

Prospective memory (PM), defining the currently conceived intention of a future action, is crucial for daily functioning, particularly in aging populations. This study develops and validates a virtual reality prospective memory training (VR–PMT) system that integrates visual imagery training (VIT) and virtual reality training (VRT) to enhance the PM abilities of users. The framework is designed to progressively challenge users by simulating real-life PM tasks in a controlled VR environment. The VIT component is designed to improve the generation and utilization of visual imagery by users, while the VRT component provides PM tasks based on time and event cues within a virtual environment. The framework was evaluated on ten healthy adults (university students and elderly participants) over 9 weeks. During the initial session, the baseline PM abilities of the participants were assessed using the memory for intentions screening test (MIST). The subsequent sessions alternated between VIT and VRT with increasing task complexity. The MIST scores were significantly positively correlated with task achievement, confirming the efficacy of the system. Imagery abilities were also strongly correlated with task performance, underscoring the importance of visual imagery in PM training. Usability and user experiences, evaluated on the Jikaku-sho Shirabe questionnaire and the user experience questionnaire, indicated an overall positive user experience but higher fatigue levels in elderly participants. This study demonstrates that the VR–PMT system effectively trains and assesses PM abilities by integrating VIT and VRT, supporting its potential for broader applications in clinical settings.

We present an immersive virtual reality training system cryoVR with passive haptic feedback for training biological scientists preparing bio-sample for Cryo-Electron Microscopy (CryoEM). CryoEM requires the user to conduct careful operations on expensive delicate equipment. To minimize the risk and interruption of crucial research work, we tried to mimic the real lab using VR to let trainer practice in a virtual environment. We used 3D printed objects to provide passive haptic feedback in order to achieve a more realistic training experience. Participants are able to interact with the equipment in the virtual environment by moving or touching physical models. We developed all the necessary operations with haptic feedback, including moving, clicking, pouring, rotating, polling and pushing. By following instructions provided by our virtual reality simulator and interacting with physical objects, trainees will learn how to operate CryoEM with low cost and risk. By developing our training system, we explore the benefits, limitations and precautions of embedding haptic feedback to scientific VR training.