scholarly journals Whole-Body Pose Estimation in Physical Rider–Bicycle Interactions With a Monocular Camera and Wearable Gyroscopes

2017 ◽  
Vol 139 (7) ◽  
Author(s):  
Xiang Lu ◽  
Kaiyan Yu ◽  
Yizhai Zhang ◽  
Jingang Yi ◽  
Jingtai Liu ◽  
...  
Keyword(s):  
Pose Estimation ◽  
The Body ◽  
Lower Limbs ◽  
Human Anatomy ◽  
Whole Body ◽  
Monocular Camera ◽  
Single Feature ◽  
Estimation Scheme ◽  
Inertial Measurements ◽  
Body Pose Estimation

Pose estimation of human–machine interactions such as bicycling plays an important role to understand and study human motor skills. In this paper, we report the development of a human whole-body pose estimation scheme with application to rider–bicycle interactions. The pose estimation scheme is built on the fusion of measurements of a monocular camera on the bicycle and a set of small wearable gyroscopes attached to the rider's upper- and lower-limbs and the trunk. A single feature point is collocated with each wearable gyroscope and also on the body segment link where the gyroscope is not attached. An extended Kalman filter (EKF) is designed to fuse the visual-inertial measurements to obtain the drift-free whole-body poses. The pose estimation design also incorporates a set of constraints from human anatomy and the physical rider–bicycle interactions. The performance of the estimation design is validated through ten subject riding experiments. The results illustrate that the maximum errors for all joint angle estimations by the proposed scheme are within 3 degs. The pose estimation scheme can be further extended and used in other types of physical human–machine interactions.

Body-Segment Orientation Estimation in Rider-Bicycle Interactions With an Un-Calibrated Monocular Camera and Wearable Gyroscopes

2013 ◽  
Author(s):  
Xiang Lu ◽  
Yizhai Zhang ◽  
Kaiyan Yu ◽  
Jingang Yi ◽  
Jingtai Liu
Keyword(s):  
Low Cost ◽  
High Accuracy ◽  
Human Anatomy ◽  
Upper Limbs ◽  
Body Segment ◽  
Orientation Estimation ◽  
Monocular Camera ◽  
Estimation Scheme ◽  
Inertial Measurements ◽  
Segment Orientation

We present a real-time human body-segment (e.g., upper limbs) orientation estimation scheme in rider-bicycle interactions. The estimation scheme is built on the fusion of measurements of an un-calibrated monocular camera on the bicycle and a set of small wearable gyroscopes attached to rider’s upper limbs. The known optical features are conveniently collocated with the gyroscopes. The design of an extended Kalman filter (EKF) to fuse the vision/inertial measurements compensates for the drifting errors by directly integrating gyroscope measurements. The characteristic and constraints from human anatomy and the rider-bicycle interactions are used to enhance the EKF performance. We demonstrate the effectiveness of the estimation design through bicycle riding experiments. The attractive properties of the proposed pose estimation in human-machine interactions include low-cost, high-accuracy, and wearable configurations for outdoor personal activities. Although we only present the application for rider-bicycle interactions, the proposed estimation scheme is readily extended and used for other types of human-machine interactions.

scholarly journals Single-Network Whole-Body Pose Estimation

2019 ◽  
Author(s):  
Gines Hidalgo Martinez ◽  
Yaadhav Raaj ◽  
Haroon Idrees ◽  
Donglai Xiang ◽  
Hanbyul Joo ◽  
...  
Keyword(s):  
Pose Estimation ◽  
Whole Body ◽  
Body Pose Estimation

Human Body Pose Estimation with Particle Swarm Optimisation

2008 ◽  
Vol 16 (4) ◽  
pp. 509-528 ◽  
Author(s):  
Špela Ivekovič ◽  
Emanuele Trucco ◽  
Yvan R. Petillot
Keyword(s):  
Pose Estimation ◽  
Human Body ◽  
Particle Swarm ◽  
Search Space ◽  
The Body ◽  
Particle Swarm Optimisation ◽  
Human Body Model ◽  
Still Images ◽  
Body Pose Estimation

In this paper we address the problem of human body pose estimation from still images. A multi-view set of images of a person sitting at a table is acquired and the pose estimated. Reliable and efficient pose estimation from still images represents an important part of more complex algorithms, such as tracking human body pose in a video sequence, where it can be used to automatically initialise the tracker on the first frame. The quality of the initialisation influences the performance of the tracker in the subsequent frames. We formulate the body pose estimation as an analysis-by-synthesis optimisation algorithm, where a generic 3D human body model is used to illustrate the pose and the silhouettes extracted from the images are used as constraints. A simple test with gradient descent optimisation run from randomly selected initial positions in the search space shows that a more powerful optimisation method is required. We investigate the suitability of the Particle Swarm Optimisation (PSO) for solving this problem and compare its performance with an equivalent algorithm using Simulated Annealing (SA). Our tests show that the PSO outperforms the SA in terms of accuracy and consistency of the results, as well as speed of convergence.

scholarly journals Biomechanical factor affecting Baseball Pitching Velocity

2019 ◽  
Author(s):  
Yasushi Ota ◽  
Ryoga Kuriyama
Keyword(s):  
High Speed ◽  
Time Series Data ◽  
Three Dimensional ◽  
The Body ◽  
Lower Limbs ◽  
Whole Body ◽  
Series Data ◽  
Physical Factors ◽  
Body Parts ◽  
Joint Force

In baseball, pitchers have a central role and high-speed pitching is desirable. So far, several studies of the physical factors related to pitching form with the aim of improving the speed of pitched balls have been conducted. In this study, we used a motion capture to acquire three-dimensional (3D) time series data related to the speed of pitched balls and performed a kinetics analysis by using these acquired data. The acquired data were divided into five pitching phases: wind up, early cocking, late cocking, acceleration, and follow through. Our analysis identified the body parts that contribute to increasing the speed of pitched balls, i.e., the speed of rotation of individual joints and the timing/phase when power can be applied. Especially, by examining joint angular velocity and joint force, we showed that the speed of pitched balls is determined by the action of the upper limbs as well as the coordinated action of the whole body, particularly the lower limbs and the trunk.

scholarly journals Clinical Retrospective Analysis of Critically Severe Necrotizing Fasciitis

2020 ◽  
Author(s):  
XIAOPING YU ◽  
ZHENG GUO ◽  
JUN LIU ◽  
JIAN WU ◽  
JUNLI ZHOU
Keyword(s):  
Necrotizing Fasciitis ◽  
Pressure Ulcer ◽  
The Body ◽  
Lower Limbs ◽  
Whole Body ◽  
Comprehensive Treatment ◽  
Low Grade ◽  
Minor Trauma ◽  
Effective Manner ◽  
Local Trauma

Abstract BackgroundToexploretheclinicaldiagnosisandtreatmentoffatalnecrotizingfasciitis.MethodsRetrospective analysis of simple data from January 1, 2014 to November 1, 2019, on the clinical data of the Department of Burns, Gansu Provincial People's Hospital, and the diagnosis and treatment methods were discussed.ResultsThe usual causes of necrosis and fasciitis are as follows. 1. Small trauma such as mosquito bites, pressure sores, and local trauma; 2. Patients suffering from minor trauma did not receive regular treatment in time, and only went to the hospital when local redness, pain, and dysfunction occurred, and were misdiagnosed as cellulitis;3. When a paraplegic patient has a Sacrococcygeal pressure ulcer and has whole-body fever or low-grade fever, and there is inflammation around the pressure ulcer, and redness and swelling spread to one lower limb or both lower limbs, necrotizing fasciitis should be highly suspected; 4. Patients’ wounds cannot be debrided in a timely and effective manner. Generally, inexperienced doctors have incomplete incision and drainage, which causes necrosis to continue to spread along the fascia to the distal limbs.Conclusion1. The diagnosis of necrotizing fasciitis mainly depends on clinical manifestations, and early diagnosis is the key; 2. When the patient has local trauma with local inflammation, and fever or hypothermia throughout the body, necrotizing fasciitis should be highly suspected, and the differential diagnosis should be made with cellulitis. When it is difficult to distinguish, a diagnostic surgical incision can be performed; 3. The operation should be thorough, fully cut and drained to avoid necrosis spreading to the distal limbs along the fascial space; 4. Necrotizing fasciitis should be systemic comprehensive treatment, rational use of antibiotics, correction of water and electrolyte disorders, early active and thorough debridement, and effective sealing of the wound.

scholarly journals Relation Between Episiotomy and Osteomioarticular Symptoms

2016 ◽  
Vol 12 (30) ◽  
pp. 353
Author(s):  
Cibele Nazaré Câmara Rodrigues ◽  
Milton Fernandes da Conceição Filho ◽  
Diego Sá Guimarães da Silva ◽  
Carla Cristina Alvarez Serrão ◽  
Carla Iasmin Lima Lemos
Keyword(s):  
Vaginal Delivery ◽  
Statistical Significance ◽  
The Body ◽  
Lower Limbs ◽  
Whole Body ◽  
Initial Assessment ◽  
Group I ◽  
High Prevalence ◽  
Spearman Correlation Test ◽  
Pathologic Alteration

Childbirth is a social and cultural phenomenon which has faced drastic changes from twentieth century as a shift to a gynecological position and an episiotomy routine. Fascia represents “the philosophy of the body” and any pathologic alteration in that tissue will affect the whole body. This study aims to verify the relation between episiotomy and osteomioarticular symptoms. 60 women who participated in this study were divided equally into two groups: group I (vaginal delivery with episiotomy) and group II (vaginal delivery without episiotomy). To assess them, we used an Initial assessment form and a Nordic Musculoskeletal Questionnaire. The data were analyzed with the Spearman Correlation Test and t Student Test for independent samples with a statistical significance of p≤0,05. Based on the results of the study, 60% women from group I related low back repercussions during the last year, while 53% women from group I related hip/lower limbs repercussions during the last week. Level of pain and musculoskeletal complaints prevailed in group I, as well. We concluded that there is a high prevalence of osteomioarticular symptoms in women who had episiotomy in her deliveries.

scholarly journals Bio-Inspired Take-Off Maneuver and Control in Vertical Jumping for Quadruped Robot with Manipulator

Micromachines ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1189
Author(s):  
Ru Kang ◽  
Fei Meng ◽  
Lei Wang ◽  
Xuechao Chen ◽  
Zhangguo Yu ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Control Method ◽  
Quadruped Robot ◽  
The Body ◽  
Lower Limbs ◽  
Whole Body ◽  
Hierarchical Optimization ◽  
Arm Swing ◽  
Joint Torques ◽  
Exploration Environment

The jumping motion of legged robots is an effective way to overcome obstacles in the rugged microgravity planetary exploration environment. At the same time, a quadruped robot with a manipulator can achieve operational tasks during movement, which is more practical. However, the additional manipulator will restrict the jumping ability of the quadruped robot due to the increase in the weight of the system, and more active degrees of freedom will increase the control complexity. To improve the jumping height of a quadruped robot with a manipulator, a bio-inspired take-off maneuver based on the coordination of upper and lower limbs is proposed in this paper. The kinetic energy and potential energy of the system are increased by driving the manipulator-end (ME) to swing upward, and the torso driven by the legs will delay reaching the required peak speed due to the additional load caused by the accelerated ME. When the acceleration of ME is less than zero, it will pull the body upward, which reduces the peak power of the leg joints. Therefore, the jumping ability of the system is improved. To realize continuous and stable jumping, a control framework based on whole-body control was established, in which the quadruped robot with a manipulator was a simplified floating seven-link model, and the hierarchical optimization was used to solve the target joint torques. This method greatly simplifies the dynamic model and is convenient for calculation. Finally, the jumping simulations in different gravity environments and a 15° slope were performed. The jump heights have all been improved after adding the arm swing, which verified the superiority of the bio-inspired take-off maneuver proposed in this paper. Furthermore, the stability of the jumping control method was testified by the continuous and stable jumping.

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