Human Motion Analysis

In this paper we describe a method of automatic motion tracking of a person in a sequence of video frames. The method is suitable for tracking a person walking or running in a surveillance video captured from a single still camera. The method initially removes noise from the captured images then segments the images using frame difference and binary conversion techniques and finally tracks the person using a bounding box based on occurrence of high intensity values horizontally and vertically. Simulation results show that the method can be used for real-time tracking of humans in videos with frame-rate of 25/30 fps. In the context of a Smart-city, the purposed system serves as a part of Internet of Things (IoT) and transmits the capture video to control-center for processing.

Purpose: The Purpose of this study was to investigate ball velocity of instep and inside foot kicks of university level soccer players. Method: The participants sample consisted twenty university soccer players from Fiji National University, Fiji. All participants have minimum of four years playing experience. The participants delivered instep and inside foot kicks using the right leg. Participants wore a complete soccer kit. Two cameras were used for this study. The cameras intersected each other perpendicularly on sagittal and frontal plans. Motion Analysis Tools (MAT) software was used to determine the ball velocity and IBM SPSS 30 was used to calculate pair t-test involving two tail tests to determine the significant difference of the ball velocity of university soccer players. Results: The results of the study indicate that the mean velocity of instep soccer kick is higher than the mean velocity of the inside foot soccer kicks. A significant difference also exists at the .05 level between the instep and the inside foot soccer kicks of the participants. Conclusion: It can be concluded that the inside foot kick resulted in a lower ball velocity than the instep kick on the part of the university level players.

— In this paper, the accuracy evaluation of the Kinect v2 sensor is investigated in a rehabilitation scenario. The accuracy analysis is provided in terms of joint positions and angles during dynamic postures used in low-back pain rehabilitation. Although other studies have focused on the validation of the accuracy in terms of joint angles and positions, they present results only considering static postures whereas the rehabilitation exercise monitoring involves to consider dynamic movements with a wide range of motion and issues related to the joints tracking. In this work, joint positions and angles represent clinical features, chosen by medical staff, used to evaluate the subject's movements. The spatial and temporal accuracy is investigated with respect to the gold standard, represented by a stereophotogrammetric system, characterized by 6 infrared cameras. The results provide salient information for evaluating the reliability of Kinect v2 sensor for dynamic postures.

In recent years, the availability of inexpensive depth cameras, such as the Microsoft Kinect, has boosted the research in monocular full body skeletal pose tracking. Unfortunately , existing trackers often fail to capture poses where a single camera provides insufficient data, such as non-frontal poses, and all other poses with body part oc-clusions. In this paper, we present a novel sensor fusion approach for real-time full body tracking that succeeds in such difficult situations. It takes inspiration from previous tracking solutions, and combines a generative tracker and a dis-criminative tracker retrieving closest poses in a database. In contrast to previous work, both trackers employ data from a low number of inexpensive body-worn inertial sensors. These sensors provide reliable and complementary information when the monocular depth information alone is not sufficient. We also contribute by new algorithmic solutions to best fuse depth and inertial data in both trackers. One is a new visibility model to determine global body pose, occlusions and usable depth correspondences and to decide what data modality to use for discriminative tracking. We also contribute with a new inertial-based pose retrieval, and an adapted late fusion step to calculate the final body pose.

The aim of this study was to investigate the effect of weight cutting and 18 hours rehydration in wrestlers' techniques performance. Methods: twenty-five men elite wrestlers participated in study, they randomly are divided into: group A (age of 18.38 ± 1.32 years, height 1.70 ± 0.04 m, weight 71.11 ± 11.80 kg) and group B (age of 21.00 ± 2.08 years, height 1.75 ± 0.04 m, weight 76.25 ± 12.55 kg). Body composition, biomechanical analysis were measure before dehydration, after weight cutting and after 18 hours rehydration. All subjects were dehydrated 3.5% of their body weight. Group A lost body weight in sauna and group B dehydrated according to active method. Single takedown technique's biomechanical parameters are measured in six points of body (both side). Three dimensional motion analysis and Skillspector software (version 1.3.2) is used to calculated right and left shoulder, pelvis, and knee linear velocity, left/right trunk, thigh segment angular velocity, and position. Reflective body markers attached all of the subjects' joints, and we used hero 3 camera @15fps/1440 p. Results with repeated measure and independent T-test showed that biomechanical characteristics decrease significantly after weight cutting (P < 0.05). Compare groups showed that dehydration by sauna have significantly more negative effect than active method. 18-hour rehydration period is not sufficient for recovery.

This article deals with the philosophical idea of worldmaking pursued through techné, meaning the fusion of the technical means of artistic creation, theorizing, and analysis, but specifically occurring in a feedback loop involving introspection and computation (cybernetic phenomenology). The discussion ranges over a wide variety of topics, including (1) the history of music theory from Ancient Greece to the present (including a rebuttal to Daniel Chua’s (2001) account of music history); (2) emergent properties in music arising from self-organization (explored through the Ancient Chinese abstract strategy board game go); (3) the ontology of musical qualities (properties) and categories (including their relation to visual, tactile, and olfactory qualities and categories). 
Various repertoires, artists, and philosophies are referenced. The essay analyzes aspects of Ligeti’s Violin Concerto, Carter’s String Quartet No. 5, and Lachenmann’s Kinderspiel.  Connections to the author’s own previous analytical and theoretical work are also discussed in relation to his interactive algorithmic audio-visual works (such as Fluxations and FluxNOISations). The techné of these is discussed in terms of logistics as well as aesthetic influences, including Wagner, Liszt, Stravinsky, Schoenberg, Crawford, Babbitt, Carter, Xenakis, Parker, Reich, Ligeti, Truax, Oliveros, Kandinsky, Miro, Pollock, Pollock, Hofmann, Rothko, Louis, Frankenthaler, Moholy-Nagy, Newman, Richter, and Brakhage.  The essay touches on philosophical ideas of Bergson, Whitehead, Deleuze, Harman, and Bogost, and more fully engages the philosophies of Nelson Goodman and Hannah Arendt in connection with artistic creation as relating to the theorizing and analysis of artistic works.     

Contact the author at jmailman@alumni.uchicago.edu
Download the article through JSTOR: http://www.jstor.org/stable/10.7757/persnewmusi.54.1.0005
or http://tinyurl.com/zdvkllr

Human Motion Analysis (HMA) is currently one of the most popularly active research domains as such significant research interests are motivated by a number of real world applications such as video surveillance, sports analysis, healthcare monitoring and so on. However, most of these real world applications face high levels of uncertainties that can affect the operations of such applications. Hence, the fuzzy set theory has been applied and showed great success in the recent past. In this paper, we aim at reviewing the fuzzy set oriented approaches for HMA, individuating how the fuzzy set may improve the HMA, envisaging and delineating the future perspectives. To the best of our knowledge, there is not found a single survey in the current literature that has discussed and reviewed fuzzy approaches towards the HMA. For ease of understanding, we conceptually classify the human motion into three broad levels: Low-Level (LoL), Mid-Level (MiL), and High-Level (HiL) HMA.

This paper describes a first principles approach to understanding how 3D digital animation of human motion can be processed and produced from raw data, without the use of proprietary software. The paper describes how students collected motion data using a custom marker set, how this was used to create a point cloud, how errors were corrected, and finally how the skeleton was rigged, skinned and modelled in Maya.

The field of interactive music systems (IMSs), beginning in the 1980s, is still relatively young and fast moving. The field of music theory-analysis, during the same period (since 1980), has undergone a major transformation in terms of technological innovations, flexibility, and breadth. The two fields have not really caught up with each other. It will be interesting to see what arises as they do — especially as both fields have become more concerned with the role of the body and embodied cognition. Framed in terms of contrasting epistemological orientations, this essay considers some relevant developments in IMSs, music cognition, and music theory and analysis, leading up to the present.  The most popular approaches to music cognition and to IMS design are rationalist (Ashby 2010), exploiting the ‘correct’ embodiments of music (Godøy 2004, Leman 2007, Paine 2009) based on affordances (Gibson 1977, Kelso 1998). This essay, however, advocates a pragmatist (Ashby 2010) approach inspired by music analysis and exploiting the potential of kinesthetic learning (associative learning). Prompted by a progressive approach to music analysis, theory, perception, and cognition (Dubiel 1999, Mailman 2007), interactive music technology can also be constructive, flexible, and progressive, by exploiting kinesthetic learning from immersion in new and unusual motion-to-sound mappings derived from dynamic formal processes in analysed music. In this way, immersive interactive systems offer an opportunity systematically to learn new associations based on principles theorised in response to analysis. Experience of these systems essentially ‘rewires the brain’, thereby exemplifying what Korsyn (2004) has attributed to Lewin’s (1986, 1987) approach to music perception: the ironist approach, as formulated by Rorty (1989). Thus a pragmatist ironist experimental (PIE) approach is articulated. Rather than committing to any particular ways music is already embodied, this approach acknowledges the flexible nature of embodied musical experience. It forges and uses interactive music technologies continually to redescribe and therefore reform how music is embodied, thereby disembodying to re-embody music, expanding how music is heard, contemplated and experienced.

Harvesting electrical energy from various human motions using piezoelectric energy harvesters (PEH) is gaining research attention in recent years. The energy harvested could potentially power hand held electronic devices and medical devices without the need of external power source for recharging batteries. In this study, an attempt is made to improve the efficiency of PEH to harvest energy from human motions by adopting a double pendulum system coupled with magnetic force interactions. For the purpose of comparison, three configurations of PEH which includes the conventional PEH with cantilever beam (PEHCB), the PEH with single pendulum system (PEHSP) and the PEH with double pendulum system (PEHDP) are experimentally studied. Excitations by both mechanical shaker and major human body parts during walking and jogging motions are investigated. The performance of each configuration, in terms of voltage and power produced as well as the idle time between each cycle, are analysed, compared and discussed. ANSYS© software is used to analyse the proposed model and MAT-LAB© software is used to calculate the output power. The results demonstrate that, with the use of the proposed double pendulum system, multiple impacts in each motion cycle is generated, thus producing higher voltage and power as compared to the conventional PEHCB. The idle time between each motion cycle is also effectively reduced. The efficiency of the PEH is thus significantly increased.

Although several studies have used wearable sensors to analyze human lifting, this has generally only been done in a limited manner. In this proof-of-concept study, we investigate multiple aspects of offline lift characterization using wearable inertial measurement sensors: detecting the start and end of the lift and classifying the vertical movement of the object, the posture used, the weight of the object, and the asymmetry involved. In addition, the lift duration, horizontal distance from the lifter to the object, the vertical displacement of the object, and the asymmetric angle are computed as lift parameters. Twenty-four healthy participants performed two repetitions of 30 different main lifts each while wearing a commercial inertial measurement system. The data from these trials were used to develop, train, and evaluate the lift characterization algorithms presented. The lift detection algorithm had a start time error of 0.10 s ± 0.21 s and an end time error of 0.36 s ± 0.27 s across all 1489 lift trials with no missed lifts. For posture, asymmetry, vertical movement, and weight, our classifiers achieved accuracies of 96.8%, 98.3%, 97.3%, and 64.2%, respectively, for automatically detected lifts. The vertical height and displacement estimates were, on average, within 25 cm of the reference values. The horizontal distances measured for some lifts were quite different than expected (up to 14.5 cm), but were very consistent. Estimated asymmetry angles were similarly precise. In the future, these proof-of-concept offline algorithms can be expanded and improved to work in real-time. This would enable their use in applications such as real-time health monitoring and feedback for assistive devices.

Human motion analysis via computer vision is an important aspect in a wide range of application; ranging from human-computer interaction (HCI) to ergonomics and biomechanics. This paper presents an overview of all processes involved in human motion analysis using computer vision-namely experimental protocol, data acquisition, data analysis and modeling. The posture adopted by the body during lifting task is thought to have a profound impact on low back. Otherwise, alteration of muscle pattern and biomechanical loads may show significant effects on human posture. The focus is on human posture modeling using motion analysis for lifting task will be investigated.

The effect of user experience on user satisfaction metrics in using MYO armband (hand gesture navigation) to control interactive maps and various other applications is still in a research state. In general, usability can be measured in terms of effectiveness, efficiency and satisfaction based on the metrics-task completion, error counts, task times and satisfaction scores. In this paper, we considered only satisfaction metrics. A simple and widely used System Usability Scale (SUS) questionnaire model is implemented to suggest some guidelines about the use of MYO armband. Another questionnaire, with a focus on ergonomic issues related to the use of the device such as Social Acceptability, Ease of use and ease of learning, Comfort and Stress, attempted do discover characteristics of hand gesture navigation using MYO. The results of this study can be used in a way to support the development of interactive maps using hand gesture navigation.

Digital Movement addresses the evolving ways in which movement and its technological mediation can inform creative thinking and embodied practices. In order to identify unique cross-disciplinary links within human movement research this book brings together experts from a number of creative disciplines including dance, theatre, sculpture, as well as computer and mathematical art, whilst offering an integration of scholarly perspectives from cultural, media and performance studies. Drawing also on historical and contemporary perspectives, the book argues that technology has become central to the way we understand and utilize movement material across a number of industries. Computer tools afford, amongst other things, customized ways to capture, sample, notate, animate, choreograph, visualize and sculpt movement. More importantly, computers also transform how we think about motion, or rather, how we think in motion-inviting us to do so collaboratively and holistically. Digital Movement shows that the technologization of human movement is a phenomenon that has the potential to have both enhancing and disturbing effects on our lives. This is an important study for all scholars and upper-level students of contemporary movement practice and performance.

Background: Gait and balance deficits are reported in adults with HIV infection and are associated with reduced quality of life. Current research suggests an increased fall-incidence in this population, with fall rates among middle-aged adults with HIV approximating that in seronegative elderly populations. Gait and postural balance rely on a complex interaction of the motor system, sensory control, and cognitive function. However, due to disease progression and complications related to ongoing inflammation, these systems may be compromised in people with HIV. Consequently, locomotor impairments may result that can contribute to higher-than-expected fall rates. The aim of this review was to synthesize the evidence regarding objective gait and balance impairments in adults with HIV, and to emphasize those which could contribute to increased fall risk. Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An electronic search of published observational studies was conducted in March 2016. Methodological quality was assessed using the NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Narrative synthesis of gait and balance outcomes was performed, and meta-analyses where possible. Results: Seventeen studies were included, with fair to low methodological quality. All studies used clinical tests for gait-assessment. Gait outcomes assessed were speed, initiation-time and cadence. No studies assessed kinetics or kinematics. Balance was assessed using both instrumented and clinical tests. Outcomes were mainly related to center of pressure, postural reflex latencies, and timed clinical tests. There is some agreement that adults with HIV walk slower and have increased center of pressure excursions and-long loop postural reflex latencies, particularly under challenging conditions. Conclusions: Gait and balance impairments exist in people with HIV, resembling fall-associated parameters in the elderly. Impairments are more pronounced during challenging conditions, might be associated with disease severity, are not influenced by antiretroviral therapy, and might not be associated with peripheral neuropathy. Results should be interpreted cautiously due to overall poor methodological quality and heterogeneity. Locomotor impairments in adults with HIV are currently insufficiently quantified. Future research involving more methodological uniformity is warranted to better understand such impairments and to inform clinical decision-making, including fall-prevention strategies, in this population.

The purpose of this study was to investigate, in 3-Dimensional (3D) space, the differences in lower limb kinematics between land-based walking (WL) and aquatic-based (WA). Twenty six male subjects (58 ± 5 years, 1.68 ± 0.50 m and 70.8 ± 11.9 kg) walked at self-selected pace in both conditions. Motion capture systems were used to quantify the toe-out-angle (TOA), stride length (SL), step-width (SW) and the hip and knee joint kinematics for both conditions. SW (0.10 ± 0.05 m vs 0.07 ± 0.03 m) and TOA (14 ± 6° vs 12 ± 5°) were significantly larger for WA than WL. However, WA resulted in significantly smaller SL (1.2 ± 0.1 m vs 0.9 ± 0.2 m), hip abduction/adduction range of motion (ROM) (6 ± 2° vs 13 ± 3°), knee abduction/adduction ROM (3 ± 1° vs 5 ± 2°), knee internal/external rotation ROM (3 ± 1° vs 6 ± 2°) and knee flexion/extension ROM (51 ± 14° vs 59 ± 4°) than WL. The results suggest that gait parameters and kinematics may have different associations for aquatic and land-based conditions. These findings could be used to facilitate a reference or guide which could be beneficial for patients with knee osteoarthritis (OA). It may also facilitate practitioners in the application of aquatic therapy as a form of gait training for patients with knee OA.

This paper presents a novel view independent approach on silhouette based human motion analysis for gait recognition applications. Spatio-temporal 1-D signals based on the differences between the outer of binarized silhouette of a motion object and a bounding box placed around silhouette are chosen as the basic image features called the distance vectors. The distance vectors are extracted using four view directions to silhouette. Gait cycle estimation and motion analysis are then performed by using normalized correlation on the distance vectors. Initial experiments for human identification are finally presented. Experimental results on the different test image sequences demonstrate that the proposed algorithm has an encouraging performance with relatively robust, low computational cost, and recognition rate for gait-based human identification.

Rapid weight loss and weight cutting are two widely used methods to reach competition weight; Sauna and dehydration as well as sweating through physical activity are very common. Many athletes with specific weight classifications such as wrestling, judo, and weight lifting want to participate in competitions 6-8 % below their normal weight. The aim of this study was to present an example of the quantitative contribution of modern sport biomechanics. The results showed that rapid weight loss could affect elite wrestlers 'performance techniques. These tests were performed in three, phases: pre-test (without dehydration), post-test1 (dehydration 3.5 %), and post-test2 (18 hours after rehydration). Thirteen experienced and elite wrestlers who had been training for 8 years participated as subjects (age 18.38 ±1.32yrs, height 1.70±0.04 m; body mass 71/111±11.80 kg). Reflective body markers attached all of the subjects' joints, and they performed single-leg takedown in front of three cameras (hero 3 @15fps/1440 p). 3D motion analyses method measured linear and angular kinematic characteristics were evaluated by Skillspector (1.3.2 version) software. Statistical analysis via the parametric and non-parametric Wilcoxon Rank-sum test and Repeated Measure test showed significant differences between the single-leg takedown techniques. The finding demonstrated negative effects on shoulders, pelvises, and knees linear max velocity, position, and angular max velocity.

Research in the video surveillance is gaining more popularity due to its widespread applications as well as social impact. In this paper, we present an intelligent framework for detection of multiple events in surveillance videos. Based on the principle of compositionality, we modularize the surveillance problems into a set of variables comprising regions-of-interest, classes (i.e. human, vehicle), attributes (i.e. speed, locality) and a set of notions (i.e. rules) associated to each of the attributes to construct a knowledge- based understanding of the environment. The final output from the reasoning process, which combines the definition domains of the various variables, allows a broader and integrated understanding of com- plex pattern of activities in the scene. This is in contrast to the state-of-the-art solutions that are only able to perform only a singular task, at a time. Experimental results on both the public and real-time datasets have demonstrated the effectiveness and robustness of the proposed framework in detecting multiple events in surveillance videos.

This paper proposes a fuzzy qualitative approach to vision-based human motion analysis with an emphasis on human motion recognition. It achieves feasible computational cost for hu- man motion recognition by combining fuzzy qualitative robot kine- matics with human motion tracking and recognition algorithms. First, a data-quantization process is proposed to relax the com- putational complexity suffered from visual tracking algorithms. Second, a novel human motion representation, i.e., qualitative nor- malized template, is developed in terms of the fuzzy qualitative robot kinematics framework to effectively represent human mo- tion. The human skeleton is modeled as a complex kinematic chain, and its motion is represented by a series of such models in terms of time. Finally, experiment results are provided to demonstrate the effectiveness of the proposed method. An empirical compar- ison with conventional hidden Markov model (HMM) and fuzzy HMM (FHMM) shows that the proposed approach consistently outperforms both HMMs in human motion recognition.