The Experts below are selected from a list of 14889 Experts worldwide ranked by ideXlab platform
Lianfang Tian - One of the best experts on this subject based on the ideXlab platform.
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Research of joint-robotics-based design of biomechanics testing device on Human Spine
Sheng wu yi xue gong cheng xue za zhi = Journal of biomedical engineering = Shengwu yixue gongchengxue zazhi, 2009Co-Authors: Guoyong Deng, Lianfang Tian, Zongyuan MaoAbstract:This paper introduces the hardware and software of a biomechanical robot-based testing device. The bottom control orders, posture and torque data transmission, and the control algorithms are integrated in a unified visual control platform by Visual C+ +, with easy control and management. By using hybrid force-displacement control method to load the Human Spine, we can test the organizational structure and the force state of the FSU (Functional spinal unit) well, which overcomes the shortcomings due to the separation of the force and displacement measurement, thus greatly improves the measurement accuracy. Also it is esay to identify the spinal degeneration and the load-bearing impact on the organizational structure of the FSU after various types of surgery.
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An intelligent control method based on fuzzy logic for a robotic testing system for the Human Spine.
Journal of biomechanical engineering, 2005Co-Authors: Lianfang TianAbstract:In previous biomechanical studies of the Human Spine, we implemented a hybrid controller to investigate load-displacement characteristics. We found that measurement errors in both position and force caused the controller to be less accurate than predicted. As an alternative to hybrid control, a fuzzy logic controller (FLC) has been developed and implemented in a robotic testing system for the Human Spine. An FLC is a real-time expert system that can emulate part of a Human operator’s knowledge by using a set of action rules. The FLC provides simple but robust solutions that cover a wide range of system parameters and can cope with significant disturbances. It can be viewed as a heuristic and modular way of defining a nonlinear, table-based control system. In this study, an FLC is developed which uses the force difference and the change in force difference as the input parameters, and the displacement as the output parameter. A rule-table based on these parameters is designed for the controller. Experiments on a physical model composed of springs demonstrate the improved performance of the proposed method.
Mohamad Parnianpour - One of the best experts on this subject based on the ideXlab platform.
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load bearing and stress analysis of the Human Spine under a novel wrapping compression loading
Clinical Biomechanics, 2000Co-Authors: A Shiraziadl, Mohamad ParnianpourAbstract:Objective. To examine biomechanics of the Human Spine under a novel compression loading that follows the curvature of the Spine. Design. The detailed response of the Spine is predicted and compared under various types of compression loading at different postures. Background. The posture and loading configuration could be so adjusted as to increase load-bearing capacity and stability of the Spine in compression while minimizing the muscle activity and risk of tissue injury. Methods. The nonlinear finite element formulation of wrapping elements sliding over solid body edges is developed and used to study the load-bearing capacity of simplified beam-rigid body thoracolumbar (T1–S1) and lumbosacral (L1–S1) Spines under a wrapping compression force. The load-bearing and stress analysis of a detailed model of the lumbar Spine, L1–S1, is also investigated under five wrapping loads resulting in differential compression forces at various levels. Follower load at L1, axially fixed compression at L1, and combined axially fixed compression and moments load are also considered for comparison. For the detailed model, the effect of changes in the position of wrapping elements and in the lumbar curvature on results are considered. Results. The idealized wrapping loading stiffens the Spine, allowing it to carry very large compression loads without hypermobility. It diminishes local segmental shear forces and moments as well as tissue stresses. Conclusions. In comparison to fixed axial compression, the compression loading by wrapping elements that follow the spinal curvatures increases the load-bearing capacity in compression and provides a greater margin of safety against both instability and tissue injury. Relevance These findings suggest a plausible mechanism in which postural changes and muscle activation patterns could be exploited to yield a loading configuration somewhat similar to that of the wrapping loading, i.e., the net reaction force at various levels passes through discs nearly normal to their mid-height plane. To alleviate hypermobility in compression, the wrapping loading could also allow for the application of meaningful compression loads in experimental as well as model studies of the multi-segmental spinal biomechanics.
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Stabilizing Role of Moments and Pelvic Rotation on the Human Spine in Compression
Journal of biomechanical engineering, 1996Co-Authors: Aboulfazl Shirazi-adl, Mohamad ParnianpourAbstract:The mechanisms by which the Human spinal column in neutral postures can resist relatively large axial compression forces with no abnormal motions or instabilities remain yet unknown. A nonlinear finite element study of the ligamentous thoracolumbar Spine was performed to investigate the stabilizing role of two plausible mechanisms of combined moments and pelvic rotation on the Human Spine in axial compression. The passive system, by itself was able to carry only a negligible fraction of physiological compression loads without exhibiting large motions. The unconstrained Spine was most flexible in the sagittal plane (least stiff plane). The existence of combined moments and pelvic rotation significantly increased the load-bearing capacity of the Spine so that the free standing passive thoracolumbar Spine resisted the axial compression forces of more than 1000 N with minimal displacements. The former mechanism is much more effective in stabilizing the Spine in compression than is the latter one. It is postulated that the pelvic rotation and the off-centered anterior placement of the gravity force are exploited to partially stabilize the passive Spine in compression and relieve the musculature. Previous and on-going studies support the validity of the proposed mechanisms.
Richard M. Aspden - One of the best experts on this subject based on the ideXlab platform.
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The effect of axial load on the sagittal plane curvature of the upright Human Spine in vivo
Journal of biomechanics, 2008Co-Authors: Judith R. Meakin, Francis W. Smith, Fiona J. Gilbert, Richard M. AspdenAbstract:Determining the effect of load carriage on the Human Spine in vivo is important for determining spinal forces and establishing potential mechanisms of back injury. Previous studies have suggested that the natural curvature of the Spine straightens under load, but are based on modelling and external measurements from the surface of the back. In the current study, an upright positional MRI scanner was used to acquire sagittal images of the lumbar and lower thoracic Spine of 24 subjects. The subjects were imaged in standing whilst supporting 0, 8 and 16 kg of load which was applied axially across the shoulders using an apron. An active shape model of the vertebral bodies from T10 to S1 was created and used to characterise the effect of load. The results from the shape model showed that the behaviour of the average-shaped Spine was to straighten slightly. However, the shape model also showed that the effect of load exhibited systematic variation between individuals. Those who had a smaller than average curvature before loading straightened under load, whereas those who had a greater than average curvature before loading showed an increase in curvature under load. The variation in behaviour of differently shaped Spines may have further implications for the effects of load in lifting manoeuvres and in understanding the aetiology of back pain.
Lutz Claes - One of the best experts on this subject based on the ideXlab platform.
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Anatomy of the sheep Spine and its comparison to the Human Spine.
The Anatomical record, 1997Co-Authors: Hans-joachim Wilke, Annette Kettler, K. H. Wenger, Lutz ClaesAbstract:Background The sheep Spine is often used as a model for the Human Spine, although the degree to which these Spines are anatomically comparable has yet to be categorically established. The purpose of this study was to investigate the characteristic anatomical dimensions of the sheep Spine and to compare these with existing Human data. Methods Five complete Spines were measured to determine 21 dimensions from the pedicles, spinal canal, transverse and spinous processes, facets, endplates, and disc. Results The results showed that sheep and Human vertebrae are most similar in the thoracic and lumbar regions, although they show substantial differences in certain dimensions. Morphological variations as a function of Spine level typically were well matched in the two species. Conclusions Sheep Spine may be a useful model for experiments related to the gross structure of the thoracic or lumbar Spine, with certain limitations for the cervical Spine. A thorough database has been provided for deciding the appropriateness of using the sheep Spine as a model for the Human Spine. Anat. Rec. 247:542–555, 1997. © 1997 Wiley-Liss, Inc.
Peng Yao - One of the best experts on this subject based on the ideXlab platform.
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From Human Spine to Humanoid robot torso
2016 IEEE International Conference on Mechatronics and Automation, 2016Co-Authors: Qingqing Zhang, Li Tao, Minzhou Luo, Peng YaoAbstract:In recent years, Humanoid robots have received a lot of attention. Many types of Humanoid robots have been developed. For Humanoid robots, Human-like torso features are essential in obtaining Humanlike motion features. However, there is still no satisfied torso design among them with their limited kinematic or dynamic features. It is necessary to carry out a deep study of Human torso with the aim to get more inspirations from it. For this purpose, a characterization of Human torso is carried out from a perspective of robotics. Then, a literature review of current Humanoid robots which have torsos more or less inspired from Human Spine is presented, and some representative robot torsos are analyzed in detail in order to find possible ways to improve the current design. Based on these two aspects, analysis and discussions are given as benefit for a better torso design for Humanoid robots.
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Analysis of Human Spine functionality from the perspective of Humanoid robots
2016 IEEE International Conference on Mechatronics and Automation, 2016Co-Authors: Peng Yao, Minzhou Luo, Li Tao, Qingqing ZhangAbstract:Humanoid robots are considered to be ideal partner in future life for Human beings, thus have great application prospects and attracted much attention. Bionics can bring researchers inspirations and lead to great achievements, for example, bipedal walking and dual-arm coordination have been made by bionics. Spine plays an important role in Human body motion with unique structure and brilliant properties, but spinal structure is rarely used in Humanoid robots. An analysis of the mechanical properties, function in body motion and walking of Human Spine is presented based on studying its structure and interaction with attaching muscles and other tissues, with the aim to reveal the true regulatory principle of Spine and give some inspirations for torso design of Humanoid robots.