Realistic Animation Research Articles

Theoretical and Computational Analysis of the Falling Ladder Problem

A comprehensive study of the falling ladder problem is presented. The ladder may fall naturally under the influence of gravity alone and at some point lose its contact with the wall or it may be kept in contact with the wall by a physical constraint. Several scenarios about the way the point of contact with the floor is moved are also considered. While solutions for the case of moving this point at constant velocity exist, generating such a motion requires implementation of an actuator. Here, the more general case of moving this point by an actuator at constant acceleration is presented and the required varying actuator force is calculated. Furthermore, computer simulations using MATLAB and the motion analysis tool of SolidWorks are generated to verify the theoretical results. Computer simulations are also used to display a comprehensive set of the findings. The theoretical results given in this paper can be used as benchmarks (in applications like robotics) for generating more realistic computer simulations and animations where elements behaving like the ladder discussed here are part of a mechanism.

Research on Animation Lip synchronization technology

Recently, linguistic communication and learning effect and even delivery of knowledge information and mutual communion was capacitated with English lip sync automation device and voice recognition technology based real time animation character in areas like movie, game, broadcasting, AR with application of animation lip sync. It connotes the possibility of these characters` lip sync using characteristic of animation to efficiently enhance the qualitative level of work in domestic animation creation`s linguistic expression with progress and application of automation technology. In a word, a study on development and practical use of Korean lip sync technique is needed to be made actively in industrial, technical progress of domestic animation. However, it is hard to find a research on commercialization method of Korean lip sync automation technique and excellent performance or example that these techniques were applied in domestic animation up to now. The reason that development using Korean lip sync technique on domestic animation passed unobserved could be found in problem of sociocultural awareness, production environment and functional value feature. First, in Korea, animation is recognized as subordinate part of movie genre, and sociocultural stereotype that persisted with dictionary definition and feature that unreal and non-objective illusion image with playful exaggeration and symbol that brings optical illusion through apparition of movement is also a problem. Second, labor-intensive method that mobilized many labor was used in production of traditional 2D animation, and since the production was done by specific worker with long acumen and experience, thus it requires long period of production and big consumption expense. Despite the fact that domestic animation is completed by overcoming poor surrounding with various risks, audiences yet feels that characters move their lip unlike the lines, and experience sound and image does not match, and it causes perception process of negative mental process and defensive mind like anger and distrust. These audiences of animation get interrupted to be empathized into true world that is essentially pursuing, and at the same time any kind of symbolic meaning and metonymic value also cannot be earned from animation. This researcher look at technical standard which will influence qualitative level of domestic creative animation in the future, and try to think visualization and synchronization problem in linguistic expression of character lip sync scene which is required in 3D animation in production side and audience side. This thesis try to study on need to develop related technology in the future and development plan by checking importance of Korean lip sync and current use state of technology in maker and audience of domestic animation. Also, looked at method and attitude for future creative animation to use technology with progress of animation Korean lip sync technology in technical side by emerging from non-linguistic act and behavior oriented research of animation. Also, in excellent cases of animation Korean lip sync, it could surpass the limit of children oriented domestic animation which massively produced with small scale and low budget, and contribute on newly illuminate and develop value and meaning of animation to more various and wider socio-cultural class.

Recent advances on animal models related to chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) has become an important public health problem in the world. According to reports, COPD ranks fourth in the global cause of death, causing a serious economic burden on society. The pathogenesis of COPD is complex, making it difficult to simulate the pathological changes and clinical features of COPD. Moreover, the COPD animal model has an irreplaceable role in the study of etiology, pathology and treatment. It is worth noting that the risk factors for chronic obstructive pulmonary disease persist, and the economic burden of global chronic obstructive pulmonary disease is expected to continue to increase in the coming decades. Establishing a standardized, a clinically realistic COPD animal model has always been a research direction that scholars are keen on. Therefore, it is essential to establish an economical animal model. The establishment of a suitable animal model can accurately simulate the pathological features of human chronic obstructive pulmonary disease and help to develop effective interventions and treatments in a short period of time. This review integrates the experimental animal species selected in the animal models used in COPD studies. Subsequently, different methods and mechanisms for establishing animal models were summarized according to different modeling factors. Finally, the criteria for evaluating existing animal models are discussed. It is hoped that the summary of this paper will guide the establishment of relevant animal models for future COPD research.

A Deep Learning-Based Model for Head and Eye Motion Generation in Three-party Conversations

In this paper we propose a novel deep learning based approach to generate realistic three-party head and eye motions based on novel acoustic speech input together with speaker marking (i.e., speaking time for each interlocutor). Specifically, we first acquire a high quality, three-party conversational motion dataset. Then, based on the acquired dataset, we train a deep learning based framework to automatically predict the dynamic directions of both the eyes and heads of all the interlocutors based on speech signal input. Via the combination of existing lip-sync and speech-driven hand/body gesture generation algorithms, we can generate realistic three-party conversational animations. Through many experiments and comparative user studies, we demonstrate that our approach can generate realistic three-party head-and-eye motions based on novel speech recorded on new subjects with different genders and ethnicities.

Creating impactful characters

Human motion capture using video-based or sensor-based methods gives animators the capability to directly translate complex human motions to create lifelike character animations. Advances in motion capture algorithms have improved their accuracy for estimating human generalized motion coordinates (joint angles and body positions). However, the traditional motion capture pipeline is not well suited to measure short duration, high acceleration impacts, such as running and jumping footstrikes. While high acceleration impacts have minimal influence on generalized coordinates, they play a big role in exciting soft tissue dynamics. Here we present a method for correcting motion capture trajectories using a sparse set of inertial measurement units (IMUs) collecting at high sampling rates to produce more accurate impact accelerations without sacrificing accuracy of the generalized coordinates representing gross motions. We demonstrate the efficacy of our method by correcting human motion captured experimentally using commercial motion capture systems with high rate IMUs sampling at 400Hz during basketball jump shots and running. With our method, we automatically corrected 185 jumping impacts and 1266 running impacts from 5 subjects. Post correction, we found an average increase of 84.6% and 91.1% in pelvis vertical acceleration and ankle dorsiflexion velocity respectively for basketball jump shots, and an average increase of 110% and 237% in pelvis vertical acceleration and ankle plantarflexion velocity respectively for running. In both activities, pelvis vertical position and ankle angle had small corrections on average below 2.0cm and 0.20rad respectively. Finally, when driving a human rig with soft tissue dynamics using corrected motions, we found a 143.4% and 11.2% increase in soft tissue oscillation amplitudes in basketball jump shots and running respectively. Our methodology can be generalized to correct impact accelerations for other body segments, and provide new tools to create realistic soft tissue animations during dynamic activities for more lifelike characters and better motion reconstruction for biomechanical analyses.

Interrogating the Diffusion of Metal Artefacts: A Case Study of a Type of Medieval Copper-Alloy Buckle

THIS PAPER INTRODUCES and discusses a group of broadly 14th-century single-looped buckles. These oval buckles are characterised by an outer edge which widens gradually towards its centre, thus providing a sizeable field either side of the pin rest. Two-thirds of the corpus of over 100 examples are decorated with engraved and punched motifs. These motifs comprise abstract forms, schematic or realistic vegetal or animal motifs, representations of humans and architectural features, and religious inscriptions. Such buckles are typical of the South of France, but are documented here for the first time from the eastern and southern coasts of England. Their presence in England can be framed in a commercial context; once diffused, they might have been copied, and other decorative motifs introduced in order to meet local needs. Compositional analyses revealed the existence of alloy groups with high proportions of lead or tin, potentially testifying to production in separate workshops.

Using artificial intelligence for modeling of the realistic animal behaviors in a virtual island

The remarkable development of the computer graphic techniques enables the creation and management of more realistic games and virtual environments. However, placing the Artificial Intelligence (AI) in a virtual world get making these environments both more interactive and more believable. One of the most ambitious goals of the AI is to create virtual worlds in which a big number of virtual characters or humans being interacted and behave in an autonomous way. For this purpose, placing embodied intelligence characters in a virtual world offers a unique opportunity to evaluate the AI concept.This paper introduces a Virtual Island developed in an innovative way based on fuzzy rules at the user interaction mechanism. We have used fuzzy tactics to create AI-based animals having various behavior types from an eagles’ perspective which called ‘Flight Simulation’. The simulation utilizes an eagle flying over the airspace of the Island of Chios. The AI on the ground is triggered by other animals when they enter a radius area with a certain speed defined in the software. It then decides how to behave according to health, behavior type and confidence level. Also, there is non-AI sparrow herd placed over the island to make user understand how fast he is and give the user sense of speed what can be called as an in-project feature. Consequently, the used Fuzzy Tactics have been tested in realized Unity 3D simulation. The results of the study have proven that the virtual environment consisting AI-based animals has a good performance in terms of animal-user interactions and provided satisfactory results in run time.

Efficient and realistic character animation through analytical physics-based skin deformation

Physics-based skin deformation methods can greatly improve the realism of character animation, but require non-trivial training, intensive manual intervention, and heavy numerical calculations. Due to these limitations, it is generally time-consuming to implement them, and difficult to achieve a high runtime efficiency. In order to tackle the above limitations caused by numerical calculations of physics-based skin deformation, we propose a simple and efficient analytical approach for physics-based skin deformations. Specifically, we (1) employ Fourier series to convert 3D mesh models into continuous parametric representations through a conversion algorithm, which largely reduces data size and computing time but still keeps high realism, (2) introduce a partial differential equation (PDE)-based skin deformation model and successfully obtain the first analytical solution to physics-based skin deformations which overcomes the limitations of numerical calculations. Our approach is easy to use, highly efficient, and capable to create physically realistic skin deformations.

Preperitoneal balloon tamponade and resuscitative endovascular balloon occlusion of the aorta: Alternatives to open packing for pelvic fracture-associated hemorrhage.

The objective of this study was to compare the efficacy of preperitoneal balloon tamponade (PPB), resuscitative endovascular balloon occlusion of the orta (REBOA), and open preperitoneal packing (OP) in a realistic animal model of pelvic fracture-associated hemorrhage. Thirty-nine swine underwent creation of open-book pelvic fracture and iliac vascular injury. Animals were randomized to no intervention (n = 7), OP (n = 10), PPB (n = 9), zone 1 REBOA (n = 7), and zone 3 REBOA (n = 6) at a mean arterial pressure less than 40 mm Hg from uncontrolled hemorrhage. Primary outcome was survival at 1 hour. Secondary outcomes included survival in the immediate 10 m following intervention reversal, peak preperitoneal pressure (PP), blood loss, bleed rate, and peak lactate. Prior to injury, no difference was measured between groups for weight, hemodynamics, lactate, and hematocrit (all p = NS). The injury was uniformly lethal without intervention, with survival time (mean) of 5 m, peak PP of 14 mm Hg, blood loss of 960 g, bleed rate of 450 g/m, and peak lactate of 2.6 mmol/L. Survival time (m) was extended to 44 with OP, 60 with PPB, and 60 with REBOA (p < 0.01). Peak PP (mm Hg) was 19 with OP, 23 with PPB, 10 with zone 1 REBOA, and 6 with zone 3 REBOA (p < 0.05). Blood loss (g) was 850 with OP, 930 with PPB, 610 with zone 1 REBOA, and 370 with zone 3 REBOA (p < 0.01). Peak lactate (mmol/L) was 3.3 with OP, 4.3 with PPB, 13.4 with zone 1 REBOA, and 5.3 with zone 3 REBOA (p < 0.01). Only 33% of zone 1 REBOA animals survived the initial 10 m after balloon deflation, compared to 60% for OP, 67% for PPB, and 100% for zone 3 REBOA (p < 0.01). Preperitoneal balloon tamponade and zone 3 REBOA are effective alternatives to OP in this animal model of lethal pelvic fracture-associated hemorrhage. Zone 1 REBOA extends survival time but with high mortality upon reversal.

Now You See Me, Now You Don't: Environmental Conditions, Signaler Behavior, and Receiver Response Thresholds Interact to Determine the Efficacy of a Movement-Based Animal Signal

Knowledge of the environment in which animals operate and the sensory processing demands that mediate behavior in an ecological context are crucial for understanding animal communication systems. Understanding how environmental factors constrain communication strategies requires quantifying both the signal and noise in detail, as has been demonstrated in studies of acoustic and color signals for some time. However, comparable analyzes of movement-based animal signals and the signalling environment is limited. There is now growing evidence that the dynamics of motion noise, in the form of wind-blown plant-movement, are a major sensory constraint for movement-based signals. However, progress has been limited as traditional techniques for understanding the ecological constraints on movement-based signals have proven insufficient. Our study utilized an innovative approach to quantify motion ecology by simulating a signaling animal in a natural habitat using highly realistic 3D animations, which afforded us unprecedented control over the signal and the circumstances in which signalling takes place. Using the Jacky dragon Amphibolurus muricatus as a model species, we quantified the efficacy of signal in noise under different combinations of wind and dapple light intensities, and quantified the potential benefit of signaling faster, or in different orientations relative to the background. We also examined signal performance as a function of varying receiver operating characteristics. Our results suggest that prevailing environmental conditions at the time of signaling do indeed affect the efficacy of movement-based signals, with wind and light levels interacting to influence efficacy. We found that faster speeds and selecting particular orientations can be beneficial, but signal efficacy comes down to the interaction between wind conditions, intensity of dappled light, signaler orientation and thresholds for receiver responses.

Animal Models for Selective Nerve Transfers of the upper Extremity

Nerve transfers are an important tool to restore muscle function. Despite their popularity in reconstructive surgery, their effects on the motor unit remain largely unknown. Therefore, a realistic animal model is needed for the upper extremity, which is where the majority of nerve transfers are conducted. This work shows different upper extremity nerve transfer models in the rat, where elbow flexion was restored with different types of nerve transfer in adult and neonatal rats. Anatomy and microsurgical feasibility was first evaluated in 10 adult and 5 neonate Sprague Dawley rats. In 40 rats (30 adult and 10 neonate), a nerve transfer of the whole ulnar nerve or just the deep branch was performed to reinnervate the long head of the biceps muscle. After 12 weeks of regeneration, the transfer was evaluated for functional aspects such as muscle force and weight. Neural anatomy was constant in all rats. All nerve transfers were successful and functional analyses showed a maximum tetanic muscle force of 2.47 + 0.25 N after an ulnar nerve transfer. Deep branch transfers achieved 1.96 + 0.65 N, and neonates achieved 1.1 + 0.23 N. Control side was 2.78 + 0.24 N. The muscle weight was 325.6 + 0.24 mg for the control, 313.8 + 0.25 mg after UN transfer, 226.7 + 0.65 mg after deep branch transfer and 85.5 + 0.23 mg for neonates. For proper clinical translation, an upper extremity model is needed. Successful reinnervation in all groups was demonstrated, which indicates an excellent model for future research. Variations in functional parameters are likely the effect of different donor axon ratios. Neuronal plasticity also appears to play a major role in the regeneration potential. This work illustrates several animal models to further investigate nerve transfers on all levels of the motor unit.

A Multimodal Interface for Virtual Character Animation Based on Live Performance and Natural Language Processing

ABSTRACTVirtual character animation is receiving an ever-growing attention by researchers, who proposed already many tools with the aim to improve the effectiveness of the production process. In particular, significant efforts are devoted to create animation systems suited also to non-skilled users, in order to let them benefit from a powerful communication instrument that can improve information sharing in many contexts like product design, education, marketing, etc. Apart from methods based on the traditional Windows-Icons-Menus-Pointer (WIMP) paradigms, solutions devised so far leverage approaches based on motion capture/retargeting (the so-called performance-based approaches), on non-conventional interfaces (voice inputs, sketches, tangible props, etc.), or on natural language processing (NLP) over text descriptions (e.g., to automatically trigger actions from a library). Each approach has its drawbacks, though. Performance-based methods are difficult to use for creating non-ordinary movements (flips, handstands, etc.); natural interfaces are often used for rough posing, but results need to be later refined; automatic techniques still produce poorly realistic animations. To deal with the above limitations, we propose a multimodal animation system that combines performance- and NLP-based methods. The system recognizes natural commands (gestures, voice inputs) issued by the performer, extracts scene data from a text description and creates live animations in which pre-recorded character actions can be blended with performer’s motion to increase naturalness.

KIKS Creativity and Technology for All

Abstract To help meet an educational and societal requirement for all students to enjoy, have confidence and ability in creativity and technology, the “Kids Inspiring Kids in STEAM” (KIKS) EU project adopted an intensive Hothousing process challenging students in Finland, Spain, Hungary and the United Kingdom to engage in collaborative problem solving to develop solutions to: “How would you get your schoolmates to LOVE STEAM?” The project provided a process and technology toolkit for students, including those with special educational needs, to achieve their solutions. A completion rate of 90% suggested that all schools and students could cope with and enjoy the process and associated technology toolkit, which featured social media plus Micro:bit, Tracker and GeoGebra for data collection and modelling. We have extended the toolkit with simulation software and a graphical programming environment to produce realistic animations of objects in motion. Thus students will have a creativity and technology toolkit to experience the kinds of techniques and skills used by software engineers in the video, games and special effects industries. The toolkit will be on the GeoGebra platform which, in addition to mathematics, embraces STEAM and social media.

A MATLAB-based virtual robotics laboratory: Demonstrated by a two-wheeled inverted pendulum

In this paper, a procedure for designing a MATLAB-based virtual robotics laboratory is described that provides a realistic three-dimensional animation for the robot’s motion. The proposed laboratory allows students to obtain the linear model and stability condition of a robotic system, without getting involved in its mathematical modeling. The structure of a two-wheeled inverted pendulum robot has been used for demonstrating the laboratory’s features. As part of this virtual experiment, design and evaluation of proportional–integral–derivative, model predictive control, and fuzzy controllers for maintaining the two-wheeled inverted pendulum’s balance are considered. A set of graphical–user interfaces is designed for providing the interaction with the system. This virtual lab is readily extensible for other robotics structures and controllers, and its output data is promptly available for further analysis by other MATLAB toolboxes.

Review on 3D Facial Animation Techniques

Generating facial animation has always been a challenge towards the graphical visualization area. Numerous efforts had been carried out in order to achieve high realism in facial animation. This paper surveys techniques applied in facial animation targeting towards realistic facial animation. We discuss the facial modeling techniques from different viewpoints; related geometric-based manipulation (that can be further categorized into interpolations, parameterization, muscle-based and pseudo–muscle-based model) and facial animation techniques involving speech-driven, image-based and data-captured. The paper will summarize and describe the related theories, strength and weaknesses for each technique.

A low latency quaternion-based web transmission system for augmented reality applications

This work deals with the development and testing of a low latency Animation Transmission Technology (ATT) for augmented reality applications. This web-based transmission system based on AutoBahn Pyhton web server and WebSocket LibrarY (WSLAY) integrated clients has been studied to reduce packet header size and to simultaneously allow a large number of Users to interact with each other. The transmission system in the proposed system architecture allows motion sensor’s acquisition software to easily send compressed 3D quaternion-based data from transmitter to the rendering softwares at receiver side to generate real time 3D animation on an avatar. Furthermore, effects of lossy compression of quaternion data and server limitation have also been considered. Initial simulation test results with the Python server alongside WSLAY integrated clients with virtual motion sensors have been presented in this work. It has been evaluated that the network delay (ND) has a huge improvement from more than 300 ms to less than 25 ms at 100 Hz sensor sampling rate once lossy compression of 3D quaternion data is implemented. Furthermore, the effect of motion sensor sampling frequency and broadcast server limitation on maximum number of simultaneous users/sensors is also described in this work.

Thin-Feature-Aware Transport-Velocity Formulation for SPH-Based Liquid Animation

Realistic liquid animations with thin sheets or streams are crucial for creating fluid effects in digital media. However, it is challenging to simulate these appealing thin sheets or streams in the framework of smoothed particle hydrodynamics (SPH). The underlying reason for this challenge mainly lies in the inherent numerical instability of SPH due to inconsistent kernel interpolation, which is caused by the incomplete kernel support on the free surface and the particles’ disorder dispersion within the simulation domain. To address this challenge, we propose a novel and effective approach to ensure the consistency of kernel interpolation at both internal flow and the free surface during the simulation such that these thin features can always be well maintained. First, we introduce a transport-velocity formulation to alleviate the disorder dispersion in the liquid domain. However, this formulation can only work in the internal flow, and it fails at the free surface because it cannot accurately estimate the density of particles there. To this end, we propose adaptively correcting the underestimated density caused by the incomplete kernel support of free-surface particles, which are identified by a geometry-aware anisotropic kernel, to counteract the inconsistent interpolation on the free surface. Then, we propose a novel scheme to further filter the background pressure to enhance the interactions between the internal flow and the free surface, as well as liquid and solid, such that the thin features generated from such interactions can be realistically simulated. The proposed approach can also achieve anticlumping and regularization effects in the entire simulation domain and, hence, further enhance the thin features in liquids. We evaluate our method on a variety of benchmark examples, and the results demonstrate that our method can achieve more appealing visual effects than state-of-the-art methods by realistically simulating more vivid thin features.

Performance Driven-biped Control for Animated Human Model with Motion Synthesis Data

Games and 3D movies are mostly supported by realistic character animation performance. The behaviour of the humanoid character it is depend on the motion data itself. Therefore the complexity of character movement will determine the realism of their behaviour. Generally, Motion Capture device will provide the raw data that previously recorded from human/actor movement. However there are some problems remains challenges such as controller, physic effect, or motion combination. Our proposed approach will read the data from motion capture device then transformed into realistic behaviour in virtual environment. However, there are few difficulties on realizing this idea, such as user objective and the appropriate behaviour of virtual human. Therefore, we solve this issue by providing the biped control to overcome the complexity of motion synthesis data when it will be applied into character animation. The controller is capable to perform motion blending with inverse and forward kinematics, as a result it able to generate the realistic behaviour along with user intention. There is three main behaviour walking, steady and jogging that has value 0-100. As a result of experiment, the biped interface control is able to read data from motion capture then load and control the virtual human by manipulating the joint forces power in every movement of the characters. As future works, the external physical forces can be added as additional forces in humanoid model to provide certain effect such as: falling down, jumping or kicking and punching to generate realistic motion synthesis.

From 2D to 3D real-time expression transfer for facial animation

In this paper, we present a three-stage approach, which creates realistic facial animations by tracking expressions of a human face in 2D and transferring them to a human-like 3D model in real-time. Our calibration-free method, which is based on an average human face, does not require training. The tracking is performed using a single camera to enable several practical applications, for example, using tablets and mobile devices, and the expressions are transferred with a joint-based system to improve the quality and persuasiveness of animations. In the first step of the method, a joint-based facial rig providing mobility to pseudo-muscles is attached to the 3D model. The second stage covers the tracking of 2D positions of the facial landmarks from a single camera view and transfer of 3D relative movement data to move the respective joints on the model. The last step includes the recording of animation using a partially automated key-framing technique. Experiments on the extended Cohn-Kanade dataset using peak frames in frontal-view videos have shown that the presented method produces visually satisfying facial animations.

Editing Fluid Animation Using Flow Interpolation

The computational cost for creating realistic fluid animations by numerical simulation is generally expensive. In digital production environments, existing precomputed fluid animations are often reused for different scenes in order to reduce the cost of creating scenes containing fluids. However, applying the same animation to different scenes often produces unacceptable results, so the animation needs to be edited. In order to help animators with the editing process, we develop a novel method for synthesizing the desired fluid animations by combining existing flow data. Our system allows the user to place flows at desired positions and combine them. We do this by interpolating velocities at the boundaries between the flows. The interpolation is formulated as a minimization problem of an energy function, which is designed to take into account the inviscid, incompressible Navier-Stokes equations. Our method focuses on smoke simulations defined on a uniform grid. We demonstrate the potential of our method by showing a set of examples, including a large-scale sandstorm created from a few flow data simulated in a small-scale space.