Computer Aided Drafting Virtual Reality Interface

Computer Aided Drafting (CAD) is pervasive in engineering fields today. It has become indispensable for planning, creating, visualizing, troubleshooting, collaborating, and communicating designs before they exist in physical form. From the beginning, CAD was created to be used by means of a mouse, keyboard, and monitor. Along the way, other, more specialized interface devices were created specifically for CAD that allowed for easier and more intuitive navigation within a 3D space, but they were at best stopgap solutions. Virtual Reality (VR) allows users to navigate and interact with digital 3D objects and environments the same way they would in the real world. For this reason, VR is a natural CAD interface solution. Using VR as an interface for CAD software, creating will be more intuitive and visualizing will be second nature. For this project, a prototype VR CAD program was created using Unreal Engine for use with the HTC Vive to compare against traditional WIMP (windows, icons, menus, pointer) interface CAD programs for the time it takes to learn each program, create similar models, and impressions of using each program, specifically the intuitiveness of the user interface and model manipulation. FreeCAD, SolidWorks, and Blender were the three traditional interface modeling programs chosen to compare against VR because of their wide-spread use for modeling in 3D printing, industry, and gaming, respectively. During the course of the project, two VR modeling programs were released, Google Blocks and MakeVR Pro; because they were of a similar type as the prototype software created in Unreal Engine, they were included for comparison as part of this project. The comparison showed that the VR CAD programs were faster to learn and create models and more intuitive to use than the traditional interface CAD programs

An evaluation of asymmetric interfaces for bimanual virtual assembly with haptics

Immersive computing technology provides a human–computer interface to support natural human interaction with digital data and models. One application for this technology is product assembly methods planning and validation. This paper presents the results of a user study which explores the effectiveness of various bimanual interaction device configurations for virtual assembly tasks. Participants completed two assembly tasks with two device configurations in five randomized bimanual treatment conditions (within subjects). A Phantom Omni® with and without haptics enabled and a 5DT Data Glove were used. Participant performance, as measured by time to assemble, was the evaluation metric. The results revealed that there was no significant difference in performance between the five treatment conditions. However, half of the participants chose the 5DT Data Glove and the haptic-enabled Phantom Omni® as their preferred device configuration. In addition, qualitative comments support both the preference of haptics during the assembly process and comments confirming Guiard’s kinematic chain model

3D model reconstruction using neural gas accelerated on GPU

In this work, we propose the use of the neural gas (NG), a neural network that uses an unsupervised Competitive Hebbian Learning (CHL) rule, to develop a reverse engineering process. This is a simple and accurate method to reconstruct objects from point clouds obtained from multiple overlapping views using low-cost sensors. In contrast to other methods that may need several stages that include downsampling, noise filtering and many other tasks, the NG automatically obtains the 3D model of the scanned objects. To demonstrate the validity of our proposal we tested our method with several models and performed a study of the neural network parameterization computing the quality of representation and also comparing results with other neural methods like growing neural gas and Kohonen maps or classical methods like Voxel Grid. We also reconstructed models acquired by low cost sensors that can be used in virtual and augmented reality environments for redesign or manipulation purposes. Since the NG algorithm has a strong computational cost we propose its acceleration. We have redesigned and implemented the NG learning algorithm to fit it onto Graphics Processing Units using CUDA. A speed-up of 180× faster is obtained compared to the sequential CPU version.This work was partially funded by the Spanish Government DPI2013-40534-R grant

The challenges in computer supported conceptual engineering design

Computer Aided Engineering Design (CAED) supports the engineering design process during the detail design, but it is not commonly used in the conceptual design stage. This article explores through literature why this is and how the engineering design research community is responding through the development of new conceptual CAED systems and HCI (Human Computer Interface) prototypes. First the requirements and challenges for future conceptual CAED and HCI solutions to better support conceptual design are explored and categorised. Then the prototypes developed in both areas, since 2000, are discussed. Characteristics already considered and those required for future development of CAED systems and HCIs are proposed and discussed, one of the key ones being experience. The prototypes reviewed offer innovative solutions, but only address selected requirements of conceptual design, and are thus unlikely to not provide a solution which would fit the wider needs of the engineering design industry. More importantly, while the majority of prototypes show promising results they are of low maturity and require further development

Expressive cutting, deforming, and painting of three-dimensional digital shapes through asymmetric bimanual haptic manipulation

Practitioners of the geosciences, design, and engineering disciplines communicate complex ideas about shape by manipulating three-dimensional digital objects to match their conceptual model. However, the two-dimensional control interfaces, common in software applications, create a disconnect to three-dimensional manipulations. This research examines cutting, deforming, and painting manipulations for expressive three-dimensional interaction. It presents a cutting algorithm specialized for planning cuts on a triangle mesh, the extension of a deformation algorithm for inhomogeneous meshes, and the definition of inhomogeneous meshes by painting into a deformation property map. This thesis explores two-handed interactions with haptic force-feedback where each hand can fulfill an asymmetric bimanual role. These digital shape manipulations demonstrate a step toward the creation of expressive three-dimensional interactions

User-based gesture vocabulary for form creation during a product design process

There are inconsistencies between the nature of the conceptual design and the functionalities of the computational systems supporting it, which disrupt the designers’ process, focusing on technology rather than designers’ needs. A need for elicitation of hand gestures appropriate for the requirements of the conceptual design, rather than those arbitrarily chosen or focusing on ease of implementation was identified.The aim of this thesis is to identify natural and intuitive hand gestures for conceptual design, performed by designers (3rd, 4th year product design engineering students and recent graduates) working on their own, without instruction and without limitations imposed by the facilitating technology. This was done via a user centred study including 44 participants. 1785 gestures were collected. Gestures were explored as a sole mean for shape creation and manipulation in virtual 3D space. Gestures were identified, described in writing, sketched, coded based on the taxonomy used, categorised based on hand form and the path travelled and variants identified. Then they were statistically analysed to ascertain agreement rates between the participants, significance of the agreement and the likelihood of number of repetitions for each category occurring by chance. The most frequently used and statistically significant gestures formed the consensus set of vocabulary for conceptual design. The effect of the shape of the manipulated object on the gesture performed, and if the sequence of the gestures participants proposed was different from the established CAD solid modelling practices were also observed.Vocabulary was evaluated by non-designer participants, and the outcomes have shown that the majority of gestures were appropriate and easy to perform. Evaluation was performed theoretically and in the VR environment. Participants selected their preferred gestures for each activity, and a variant of the vocabulary for conceptual design was created as an outcome, that aims to ensure that extensive training is not required, extending the ability to design beyond trained designers only.There are inconsistencies between the nature of the conceptual design and the functionalities of the computational systems supporting it, which disrupt the designers’ process, focusing on technology rather than designers’ needs. A need for elicitation of hand gestures appropriate for the requirements of the conceptual design, rather than those arbitrarily chosen or focusing on ease of implementation was identified.The aim of this thesis is to identify natural and intuitive hand gestures for conceptual design, performed by designers (3rd, 4th year product design engineering students and recent graduates) working on their own, without instruction and without limitations imposed by the facilitating technology. This was done via a user centred study including 44 participants. 1785 gestures were collected. Gestures were explored as a sole mean for shape creation and manipulation in virtual 3D space. Gestures were identified, described in writing, sketched, coded based on the taxonomy used, categorised based on hand form and the path travelled and variants identified. Then they were statistically analysed to ascertain agreement rates between the participants, significance of the agreement and the likelihood of number of repetitions for each category occurring by chance. The most frequently used and statistically significant gestures formed the consensus set of vocabulary for conceptual design. The effect of the shape of the manipulated object on the gesture performed, and if the sequence of the gestures participants proposed was different from the established CAD solid modelling practices were also observed.Vocabulary was evaluated by non-designer participants, and the outcomes have shown that the majority of gestures were appropriate and easy to perform. Evaluation was performed theoretically and in the VR environment. Participants selected their preferred gestures for each activity, and a variant of the vocabulary for conceptual design was created as an outcome, that aims to ensure that extensive training is not required, extending the ability to design beyond trained designers only