3D Shape Reconstruction from Sketches via Multi-view Convolutional Networks

We propose a method for reconstructing 3D shapes from 2D sketches in the form of line drawings. Our method takes as input a single sketch, or multiple sketches, and outputs a dense point cloud representing a 3D reconstruction of the input sketch(es). The point cloud is then converted into a polygon mesh. At the heart of our method lies a deep, encoder-decoder network. The encoder converts the sketch into a compact representation encoding shape information. The decoder converts this representation into depth and normal maps capturing the underlying surface from several output viewpoints. The multi-view maps are then consolidated into a 3D point cloud by solving an optimization problem that fuses depth and normals across all viewpoints. Based on our experiments, compared to other methods, such as volumetric networks, our architecture offers several advantages, including more faithful reconstruction, higher output surface resolution, better preservation of topology and shape structure.Comment: 3DV 2017 (oral

Gamification of assembly planning in virtual environment

Purpose: The purpose of this paper is to study the effect of the gamification of virtual assembly planning on the user performance, user experience and engagement. / Design/methodology/approach: A multi-touch table was used to manipulate virtual parts and gamification features were integrated into the virtual assembly environment. An experiment was conducted in two conditions: a gamified and a non-gamified virtual environment. Subjects had to assemble a virtual pump. The user performance was evaluated in terms of the number of errors, the feasibility of the generated assembly sequence and the user feedback. / Findings: The gamification reduced the number of errors and increased the score representing the number of right decisions. The results of the subjective and objective analysis showed that the number of errors decreased with engagement in the gamified assembly. The increase in the overall user experience reduced the number of errors. The subjective evaluation showed a significant difference between the gamified and the non-gamified assembly in terms of the level of engagement, the learning usability and the overall experience. / Research limitations/implications: The effective learning retention after training has not been tested, and longitudinal studies are necessary. The effect of the used gamification elements has been evaluated as a whole; further work could isolate the most beneficial features and add other elements that might be more beneficial for learning. / Originality/value: The research reported in this paper provides valuable insights into the gamification of virtual assembly using a low-cost multi-touch interface. The results are promising for training operators to assemble a product at the design stage

An evaluation of user experience with a sketch-based 3D modeling system

Abstract With the availability of pen-enabled digital hardware, sketch-based 3D modeling is becoming an increasingly attractive alternative to traditional methods in many design environments. To date, a variety of methodologies and implemented systems have been proposed that all seek to make sketching the primary interaction method for 3D geometric modeling. While many of these methods are promising, a general lack of end user evaluations makes it difficult to assess and improve upon these methods. Based on our ongoing work, we present the usage and a user evaluation of a sketch-based 3D modeling tool we have been developing for industrial styling design. The study investigates the usability of our techniques in the hands of non-experts by gauging (1) the speed with which users can comprehend and adopt to constituent modeling steps, and (2) how effectively users can utilize the newly learned skills to design 3D models. Our observations and users' feedback indicate that overall users could learn the investigated techniques relatively easily and put them in use immediately. However, users pointed out several usability and technical issues such as difficulty in mode selection and lack of sophisticated surface modeling tools as some of the key limitations of the current system. We believe the lessons learned from this study can be used in the development of more powerful and satisfying sketch-based modeling tools in the future.

Sketch-based digital storyboards and floor plans for authoring computer-generated film pre-visuals

Pre-visualisation is an important tool for planning films during the pre-production phase of filmmaking. Existing pre-visualisation authoring tools do not effectively support the user in authoring pre-visualisations without impairing software usability. These tools require the user to either have programming skills, be experienced in modelling and animation, or use drag-and-drop style interfaces. These interaction methods do not intuitively fit with pre-production activities such as floor planning and storyboarding, and existing tools that apply a storyboarding metaphor do not automatically interpret user sketches. The goal of this research was to investigate how sketch-based user interfaces and methods from computer vision could be used for supporting pre-visualisation authoring using a storyboarding approach. The requirements for such a sketch-based storyboarding tool were determined from literature and an interview with Triggerfish Animation Studios. A framework was developed to support sketch-based pre-visualisation authoring using a storyboarding approach. Algorithms for describing user sketches, recognising objects and performing pose estimation were designed to automatically interpret user sketches. A proof of concept prototype implementation of this framework was evaluated in order to assess its usability benefit. It was found that the participants could author pre-visualisations effectively, efficiently and easily. The results of the usability evaluation also showed that the participants were satisfied with the overall design and usability of the prototype tool. The positive and negative findings of the evaluation were interpreted and combined with existing heuristics in order to create a set of guidelines for designing similar sketch-based pre-visualisation authoring tools that apply the storyboarding approach. The successful implementation of the proof of concept prototype tool provides practical evidence of the feasibility of sketch-based pre-visualisation authoring. The positive results from the usability evaluation established that sketch-based interfacing techniques can be used effectively with a storyboarding approach for authoring pre-visualisations without impairing software usability

Sketch-based digital storyboards and floor plans for authoring computer-generated film pre-visuals

Pre-visualisation is an important tool for planning films during the pre-production phase of filmmaking. Existing pre-visualisation authoring tools do not effectively support the user in authoring pre-visualisations without impairing software usability. These tools require the user to either have programming skills, be experienced in modelling and animation, or use drag-and-drop style interfaces. These interaction methods do not intuitively fit with pre-production activities such as floor planning and storyboarding, and existing tools that apply a storyboarding metaphor do not automatically interpret user sketches. The goal of this research was to investigate how sketch-based user interfaces and methods from computer vision could be used for supporting pre-visualisation authoring using a storyboarding approach. The requirements for such a sketch-based storyboarding tool were determined from literature and an interview with Triggerfish Animation Studios. A framework was developed to support sketch-based pre-visualisation authoring using a storyboarding approach. Algorithms for describing user sketches, recognising objects and performing pose estimation were designed to automatically interpret user sketches. A proof of concept prototype implementation of this framework was evaluated in order to assess its usability benefit. It was found that the participants could author pre-visualisations effectively, efficiently and easily. The results of the usability evaluation also showed that the participants were satisfied with the overall design and usability of the prototype tool. The positive and negative findings of the evaluation were interpreted and combined with existing heuristics in order to create a set of guidelines for designing similar sketch-based pre-visualisation authoring tools that apply the storyboarding approach. The successful implementation of the proof of concept prototype tool provides practical evidence of the feasibility of sketch-based pre-visualisation authoring. The positive results from the usability evaluation established that sketch-based interfacing techniques can be used effectively with a storyboarding approach for authoring pre-visualisations without impairing software usability