Artykuły w czasopismach: „Mesoscale ball and socket joint”

1

Pistoia, F., M. B. Ozonoff i P. Wintz. "Ball-and-socket ankle joint". Skeletal Radiology 16, nr 6 (sierpień 1987): 447–51. http://dx.doi.org/10.1007/bf00350538.

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Camp, Richard A., i Michael J. Callahan. "Ball-and-socket interphalangeal joint arthrodesis". Techniques in Orthopaedics 1, nr 2 (lipiec 1986): 10–13. http://dx.doi.org/10.1097/00013611-198607000-00005.

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Ting, Kwun-Lon, i Jianmin Zhu. "On Realization of Spherical Joints In RSSR Mechanisms". Journal of Mechanical Design 127, nr 5 (4.12.2004): 924–30. http://dx.doi.org/10.1115/1.1904641.

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A spherical joint must allow adequate mobility between the ball and socket. Unless the specific geometric requirement of the spherical joint, namely the trajectory of the ball stem in the socket, is known, the realization of a synthesized mechanism containing a spherical joint can become an endless trial and error process or even a fruitless attempt. Typical examples can be found in RSSR mechanisms. For a synthesized RSSR mechanism, this paper presents the closed form equation describing the spherical trajectory of the ball in the socket and the design and manufacturing issues of the spherical joints. It offers the classification scheme of spherical joints based on the required ball rotatability in the socket and shows how the necessary socket opening of the spherical joints is affected. The size and location of the socket in a spherical joint must be properly determined to meet the rotatability requirement and in many situations, a conventional spherical joint with a circular socket opening cannot be used. Essential geometric and location information regarding to the use of non-circular socket opening, spherical grooved pair, as well as revolute joints to replace the conventional spherical joints to realize a synthesized RSSR mechanism is presented. The proposed concept and method can be extrapolated to other mechanisms containing spherical joints.

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4

Guo, Jin, Jin-Huat Low, Jun Liu, Yangfan Li, Zhuangjian Liu i Chen-Hua Yeow. "Three-Dimensional Printable Ball Joints with Variable Stiffness for Robotic Applications Based on Soft Pneumatic Elastomer Actuators". Polymers 14, nr 17 (29.08.2022): 3542. http://dx.doi.org/10.3390/polym14173542.

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This paper contributes to a new design of the three-dimensional printable robotic ball joints capable of creating the controllable stiffness linkage between two robot links through pneumatic actuation. The variable stiffness ball joint consists of a soft pneumatic elastomer actuator, a support platform, an inner ball and a socket. The ball joint structure, including the inner ball and the socket, is three-dimensionally printed using polyamide−12 (PA12) by selective laser sintering (SLS) technology as an integral mechanism without the requirement of assembly. The SLS technology can make the ball joint have the advantages of low weight, simple structure, easy to miniaturize and good MRI compatibility. The support platform is designed as a friction-based braking component to increase the stiffness of the ball joint while withstanding the external loads. The soft pneumatic elastomer actuator is responsible for providing the pushing force for the support platform, thereby modulating the frictional force between the inner ball, the socket and the support platform. The most remarkable feature of the proposed variable stiffness design is that the ball joint has ‘zero’ stiffness when no pressurized air is supplied. In the natural state, the inner ball can be freely rotated and twist inside the socket. The proposed ball joint can be quickly stiffened to lock the current position and orientation of the inner ball relative to the socket when the pressurized air is supplied to the soft pneumatic elastomer actuator. The relationship between the stiffness of the ball joint and the input air pressure is investigated in both rotating and twisting directions. The finite element analysis is conducted to optimize the design of the support platform. The stiffness tests are conducted, demonstrating that a significant stiffness enhancement, up to approximately 508.11 N·mm reaction torque in the rotational direction and 571.93 N·mm reaction torque in the twisting direction at the pressure of 400 kPa, can be obtained. Multiple ball joints can be easily assembled to form a variable stiffness structure, in which each ball joint has a relative position and an independent stiffness. Additionally, the degrees of freedom (DOF) of the ball joint can be readily restricted to build the single-DOF or two-DOFs variable stiffness joints for different robotic applications.

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5

Lewis, John S., i James K. DeOrio. "The Adult Ball-and-Socket Ankle Joint". Foot & Ankle Specialist 8, nr 2 (8.09.2014): 112–18. http://dx.doi.org/10.1177/1938640014548321.

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Stanisˇic´, M. M., i K. C. Gupta. "Closed-Form Solutions to the Spherical Joint Attachment Problem". Journal of Mechanical Design 114, nr 2 (1.06.1992): 269–73. http://dx.doi.org/10.1115/1.2916942.

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This paper presents closed-form solutions to the problem of defining the attachment of a spherical joint (a ball and socket) in a spatial linkage. The defined attachment should minimize the opening angle of the socket, maximizing the ball retention capability. Previous solutions to this problem have used iterative searching techniques, which are computationally intense. In this paper the problem is reformulated as a surface fitting problem. Two formulations are presented, both of which require the solution of the associated eigenvalue problems. The eigenvectors correspond to the central axis of symmetry for the socket opening. A numerical example is presented to compare the results obtained by these formulations with those available in the literature.

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Stanisˇic´, M. M., i W. F. Mirusky. "Optimization of Spherical Joint Attachment in Spatial Linkages". Journal of Mechanisms, Transmissions, and Automation in Design 110, nr 4 (1.12.1988): 440–45. http://dx.doi.org/10.1115/1.3258942.

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This paper presents the kinematic analysis and optimization technique required for the optimal attachment of a spherical joint (i.e., a ball in a socket) to the ground pivoted link of an RSSR spatial four-bar linkage. The optimization technique is a searching algorithm, which can be applied to the problem of optimal spherical joint attachment in other types of spatial linkages as well. This attachment optimization is necessary if the socket of the joint is to have its maximum ball retention capability. The optimization technique is illustrated by an example.

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Wang, A., A. Essner i R. Klein. "Effect of contact stress on friction and wear of ultra-high molecular weight polyethylene in total hip replacement". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 215, nr 2 (1.02.2001): 133–39. http://dx.doi.org/10.1243/0954411011533698.

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This paper studies the effect of contact stress on friction and wear of ultra-high molecular weight polyethylene (UHMWPE) acetabular cups by means of friction and wear joint simulator testing under serum lubrication. For a given applied load, increasing the contact stress by increasing the ball/socket radial clearance decreased both the coefficient of friction and the wear rate. Friction and wear were highly correlated. The dependence of friction on contact stress for the UHMWPE socket under serum lubrication was similar to that of semi-crystalline polymers under dry sliding. This finding indicates the occurrence of partial dry contact at asperity levels for the metal-polyethylene ball-in-socket joint under serum lubrication.

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9

Cho, Se Hyun, Duk Yong Lee i Hee Joong Kang. "Congenital Ball - and - Socket Ankle Joint: A Case Report". Journal of the Korean Orthopaedic Association 20, nr 1 (1985): 201. http://dx.doi.org/10.4055/jkoa.1985.20.1.201.

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DENNIS, DOUGLAS A., MACK L. CLAYTON i DONALD C. FERLIC. "Osteoarthritis Associated with a Ball-and-Socket Ankle Joint". Clinical Orthopaedics and Related Research &NA;, nr 215 (luty 1987): 196???200. http://dx.doi.org/10.1097/00003086-198702000-00028.

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Santiago, Fernando, Celestino Moreno, Luis Barea i Ernesto Bautista. "Ball-and-socket ankle joint with hypoplastic sustentaculum tali". European Radiology 12, S3 (grudzień 2002): S48—S50. http://dx.doi.org/10.1007/s00330-002-1666-x.

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Normahira, M., A. Z. Ahmad Firdaus i G. N. Molijol. "An Investigation on Rigidity of Ball-Socket Hip Joint Replacement". Applied Mechanics and Materials 754-755 (kwiecień 2015): 1059–64. http://dx.doi.org/10.4028/www.scientific.net/amm.754-755.1059.

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A 3-dimensional hip joint implant model was constructed which separates into three individual parts namely femoral stem with neck, femoral head and acetabular cup. Each part were assigned with the specific materials and a total of 3000 N loads was applied to mimic the body weight of an adult in static position or in double leg standing position. The results of the stress distribution were obtained from the finite element analysis for the difference diameter for each component of ball-socket and neck as well as the difference materials. The results showed that an optimum diameter of femoral ball-socket with 36 mm and titanium alloy have design rigidity which provided better performance and longer life span based on 13.922 Mpa equivalent stress .

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13

Gimmelmfarb, A. L. "Drill guide". Kazan medical journal 69, nr 1 (15.02.1988): 75–76. http://dx.doi.org/10.17816/kazmj97044.

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Due to the widespread use of surgical interventions that help preserve hip function in hip disease, the number of arthrodesis - traumatic interventions involving dislocation of the femoral head from the articular socket and resection of the articular surfaces - has decreased. As a rule, joint locking is now performed only in cases where there is no alternative, i.e., when there is minimal rocking motion in the joint. In such cases, the traumatic open resection arthrodesis is replaced by the less traumatic so-called closed periarticular arthrodesis. However, since closed arthrodesis is performed without dislocating the femoral ball head, the subsequent fixation of the femoral ball head in the socket is difficult.

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14

Chu, Wenmin, Xiang Huang, Shuanggao Li i Peihuang Lou. "A ball head positioning method based on hybrid force-position control". Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 235, nr 8 (18.01.2021): 1433–44. http://dx.doi.org/10.1177/0959651820987903.

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In the digital aircraft assembly system, the large component of aircraft is connected with the numerical control locator through a ball joint composed of a ball head and a ball socket. To ensure the posture adjustment accuracy of large component of aircraft, the clearance between the ball head and the ball socket is very small. Therefore, it is very difficult to accurately guide the ball head of large component of aircraft into the ball socket of the numerical control locator. Aiming at this problem, this article proposes a ball head positioning method based on hybrid force-position control, so that the ball socket can approach the ball head adaptively. First, according to the technical characteristics of the ball head positioning, the axes of the numerical control locator are divided into position control axis and force control axis, and the conditions to ensure the safety of ball head positioning are analyzed. Then the control model of ball head positioning based on hybrid force-position control is established and simulated by Simulink. Finally, a simulated posture adjustment system is built in the laboratory, and a series of ball head positioning experiments based on hybrid force-position control are carried out. The experimental results show that, compared with the traditional ball head positioning method, the ball head positioning process based on hybrid force-position control is more stable and faster, and the method can significantly reduce the lateral force. Moreover, the proposed method can be easily integrated into the existing posture adjustment system without additional hardware cost.

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15

Yang, Eileen Chih-Ying, Ming-Hsien Yen, Ming-Ti Chou, Zhen-Jia Huang i Sin-Kai Chen. "Non-spherical ball-socket joint design for Delta-type robots". Mechatronics 45 (sierpień 2017): 14–24. http://dx.doi.org/10.1016/j.mechatronics.2017.05.003.

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16

Goubau, Laurent, Chul Goorens, Petrus van Hoonacker, Diederick Kerckhove, Bert Vanmierlo, Bart Berghs i Jean Goubau. "De Quervain Tenosynovitis Following Trapeziometacarpal Ball-and-Socket Joint Replacement". Journal of Wrist Surgery 04, nr 01 (13.02.2015): 035–42. http://dx.doi.org/10.1055/s-0034-1398487.

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Fernandes, R. "A rare case of a ball and socket ankle joint". Case Reports 2011, nr 11 1 (15.11.2011): bcr1020114919. http://dx.doi.org/10.1136/bcr.10.2011.4919.

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Manring, Noah D., Chris L. Wray i Zhilin Dong. "Experimental Studies on the Performance of Slipper Bearings Within Axial-Piston Pumps". Journal of Tribology 126, nr 3 (28.06.2004): 511–18. http://dx.doi.org/10.1115/1.1698936.

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The objectives of this study are to experimentally investigate the performance characteristics of similar slipper bearings using different socket geometries. In this study, the lubrication equations for the bearing are derived based upon an assumption that the bearing deformations are small and that they may be modeled linearly. This study is based upon the hypothesis that variations in the socket geometry will impact the deformation characteristics of the bearing and thereby have an effect on the overall performance of the design. To test this hypothesis, bearings with different socket geometries are designed and tested and compared to the original bearing design with standard socket geometry. The experimental results are then used with the analytical results to numerically infer the minimum fluid-film thickness and the magnitude of deformation for the bearing. Conclusions are drawn from these results which indicate that socket geometry has a significant impact on the bearing performance and that both leakage and load-carrying capacity may be altered by adjusting the location of the contact point within the ball-and-socket joint relative to the center of the ball.

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19

Kang, Jaeyoung. "Nonlinear Vibration Induced by Friction in a Ball Joint System". Lubricants 10, nr 9 (26.08.2022): 201. http://dx.doi.org/10.3390/lubricants10090201.

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In this paper, the nonlinear oscillations induced by friction in a ball-on-socket system are investigated. The nonlinear time response was obtained by solving the differential equations of the friction-noise model of the finite element ball with multiple modes. The different patterns of motion were analyzed via the bifurcation diagram, Poincare map, and recurrence plot. The Lyapunov exponents of the discontinuous system with distributed contact were calculated using the Muller method. From the analysis, it is shown that a friction-noise of a ball joint can retain periodic, quasi-periodic, or chaotic oscillations with respect to tilted contact.

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Nam, Kwang Woo, i Sang-Rim Kim. "Anatomy of the Hip". Journal of Medicine and Life Science 6, nr 4 (1.09.2009): 220–22. http://dx.doi.org/10.22730/jmls.2009.6.4.220.

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The hip is a large ball and socket synovial joint allowing wide-range of motion. lt plays an important role as an axial weight bearing joint associated with standing. walking, and running. Physicians must understand the anatomy of the hip to assess and to treat the patients with hip problems.

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WANG, XISHI, TIANYING WANG, FUCHUAN JIANG i YIXIANG DUAN. "THE HUMAN HIP STRESS ANALYSIS: A BALL-SOCKET ELASTIC CONTACT MODELLING". Biomedical Engineering: Applications, Basis and Communications 16, nr 05 (25.10.2004): 233–37. http://dx.doi.org/10.4015/s1016237204000311.

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The peak stress, the weight bearing area and the stress distribution of the articular contact at the human hip joint is the most important factors, which determine the location of the degenerative foci that later result in degenerative damage and in the development of osteoarthritis. In the paper, a ball-socket articular elastic contact modelling of the human hip joint is successfully established. This modelling can be used to predict the peak stress, the weight bearing area and the stress distributions of the articular contact at the human hip joint. In order to verify the validation of current modelling, an example is examined. The results show that the predictions from the current modelling are basically agreement with those reported in literatures. This shows the validity of the current modelling.

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Tadesse, Yonas, Lianjun Wu i Lokesh K. Saharan. "Musculoskeletal System for Bio-Inspired Robotic Systems". Mechanical Engineering 138, nr 03 (1.03.2016): S11—S16. http://dx.doi.org/10.1115/1.2016-mar-8.

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This article presents a research focused on developing musculoskeletal system for bio-inspired robotic systems. A musculoskeletal system is the fundamental structure that allows complex mobility of biological systems. This paper briefly describes the recently introduced twisted and coiled polymer (TCP) muscles and a novel design of musculoskeletal system based on ball and socket joint, as well as their application in a 3D printed humanoid robot. The challenge to develop such systems is multifaceted, including design, manufacturing, system integration, control methods, and energy usage. Some of the challenges in humanoid design are the degrees of freedom and the synergetic combination of hardware and software to perform a particular task. The other challenge is affordability of the platform. Most humanoids are very expensive. Since the TCP-based actuators are inexpensive and musculoskeletal systems inspired by biological systems are optimum for performance, they will address these problems. The bio-inspired ball and socket joint shown in the article can be cascaded to create complex robots, for example, for the shoulder joint of a humanoid.

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23

Singh, U., i S. S. Wason. "Multiaxial orthotic hip joint for squatting and cross-legged sitting withhip-knee-ankle-foot-orthosis". Prosthetics and Orthotics International 12, nr 2 (sierpień 1988): 101–2. http://dx.doi.org/10.3109/03093648809078207.

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In view of the importance of squatting and cross-legged sitting in the activities of daily living in Asian and African countries, a multiaxial orthotic hip joint has been developed which when fitted to a Hip-Knee-Ankle-Foot-Orthosis (HKAFO) can permit the user to squat and sit cross-legged. The design consists of a modified ball and socket joint.

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Lesk, Arthur M., i Cyrus Chothia. "Elbow motion in the immunoglobulins involves a molecular ball-and-socket joint". Nature 335, nr 6186 (wrzesień 1988): 188–90. http://dx.doi.org/10.1038/335188a0.

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Sri Muthu Mrinalini, R., i G. R. Jayanth. "Design and Evaluation of an Active Micro-Scale Ball and Socket Joint". Journal of Microelectromechanical Systems 26, nr 4 (sierpień 2017): 886–94. http://dx.doi.org/10.1109/jmems.2017.2695582.

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Han, Qinghua, Yan Lu i Mingchang Jin. "Resistance partial factor and reliability of cast ball-and-socket support joint". Transactions of Tianjin University 17, nr 6 (grudzień 2011): 391–96. http://dx.doi.org/10.1007/s12209-011-1617-1.

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Duerinckx, Joris, i Frederik Verstreken. "Total joint replacement for osteoarthritis of the carpometacarpal joint of the thumb: why and how?" EFORT Open Reviews 7, nr 6 (1.06.2022): 349–55. http://dx.doi.org/10.1530/eor-22-0027.

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Total joint replacement has certain advantages over other surgical treatment methods for osteoarthritis of the thumb carpometacarpal joint, including restoration of thumb length and alignment, good cosmetical result, fast recovery of hand function and prevention of iatrogenic complications at neighbouring joints. Disadvantages include the technical difficulty to perform this surgery and a possible higher complication rate. A meticulous surgical technique is mandatory. Combined with a cementless and modular ball-in-socket implant with a metal-on-polyethylene friction couple, a 10-year survival rate higher than 90% can be expected. Revision surgery is possible with implant exchange or conversion to trapeziectomy.

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Liao, M. C., P. S. Huang, T. C. Huang i M. Y. Tsai. "Backplate-reinforced structures for enhancing solder joint reliability of server CPU assembly under thermal cycling". Journal of Mechanics 37 (2021): 693–703. http://dx.doi.org/10.1093/jom/ufab035.

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ABSTRACT To meet the requirement of the high I/O and fine-pitch interconnects, the conventional insertion-mount socket for central processing unit (CPU) has been changed to surface-mount one with ball grid array. The solder ball joint reliability of the socket used in the CPU assembly becomes very important. In this study, the socket's solder joint reliability of the backplate-reinforced CPU assembly and its related mechanics under mechanical and thermal loadings are investigated experimentally using strain gauge and shadow moiré, and numerically by a finite element method (FEM). The validated FEM results have suggested that maximum stress of solder balls increases almost linearly with decreasing the backplate thickness under mechanical loading during the CPU assembly, but is insensitive to the backplate thickness under thermal loading during the thermal cycling. It is also found that the residual (bending) strain on the PCB proportional to the maximum von Mises stresses of solder joints (or balls) can be used as a key parameter to correlate with the solder joint failures or cracks during the thermal cycling. Overall, experimental and FEM results in this study reveal that solder joint reliability in the CPU assembly during thermal cycling can be improved by adopting the thicker reinforced backplate.

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Scranton, Pierce E., i John E. McDermott. "Pathologic Anatomic Variations in Subtalar Anatomy". Foot & Ankle International 18, nr 8 (sierpień 1997): 471–76. http://dx.doi.org/10.1177/107110079701800803.

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Thirteen patients presenting with symptomatic pathologic variations or congenital deformities of the subtalar joint are presented. These variations included: four abnormal posterior talar processes, five patients with asymmetric subtalar joint development, and four congenital complete subtalar coalitions with a secondary ball-and-socket joint. In each case these adult patients had been unaware of the variation and had been symptom free until “awakening” sprain or fracture trauma brought about symptoms. The nonoperative and operative management of these variations is reviewed.

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Cho, Byung-Ki, Kyoung-Jin Park, Seung-Myung Choi, Sang-Woo Kang i Hyung-Ki Lee. "Ankle Fusion Combined With Calcaneal Sliding Osteotomy for Severe Arthritic Ball and Socket Ankle Deformity". Foot & Ankle International 37, nr 12 (20.08.2016): 1310–16. http://dx.doi.org/10.1177/1071100716661382.

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Background: Although a ball and socket ankle deformity is usually congenital and asymptomatic, abnormal inversion and eversion mobility can result in recurrent ankle sprain and osteoarthritis. This retrospective study was performed to evaluate the clinical and radiologic outcomes of ankle fusion combined with calcaneal sliding osteotomy for severe arthritic ball and socket ankle deformity. Methods: Fourteen patients with severe arthritic ball and socket ankle deformity were followed for more than 3 years after operation. The clinical evaluation consisted of American Orthopaedic Foot & Ankle Society (AOFAS) score, Foot and Ankle Ability Measure (FAAM), visual analog scale (VAS) for pain, and subjective satisfaction score. The period to fusion and union of osteotomy, the change of hindfoot alignment angle, and complications were evaluated radiologically. Results: AOFAS and FAAM scores were significantly improved from an average of 37.4 and 34.5 points to 74.6 and 78.5 points, respectively. VAS for pain with walking over 20 minutes was significantly improved from an average of 8.4 points to 1.9 points. The average satisfaction score of patients was 88.9 points. The difference in heel alignment angle (compared to contralateral side) was significantly improved from an average of 34.8 to 5.4 degrees. There were 2 cases of progressive arthritis in an adjacent joint and 1 case of failed fusion. Conclusions: Ankle fusion combined with calcaneal sliding osteotomy can be an effective operative option for ball and socket ankle deformity with advanced arthritis. In spite of increased complication rate, reliable pain relief, and restoration of gait ability through correcting hindfoot malalignment could improve the quality of life. Level of Evidence: Level IV, retrospective case series.

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Kang, Jaeyoung. "Dynamic instability of a spherical joint under various contact areas". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 229, nr 1 (17.04.2014): 54–58. http://dx.doi.org/10.1177/0954406214532077.

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The contact area and the negative friction velocity slope on dynamic instability of spherical joint are theoretically investigated. The contact area may be influenced by the various loading and design conditions between a ball and socket. The non-conformal contact is adopted for the static and dynamic derivations. This contact geometry is selected as the major design parameter in this study. The numerical results reveal that the smaller contact area produces the higher propensity of modal instability.

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Jagatia, M., i Z. M. Jin. "Elastohydrodynamic lubrication analysis of metal-on-metal hip prostheses under steady state entraining motion". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 215, nr 6 (1.06.2001): 531–41. http://dx.doi.org/10.1243/0954411011536136.

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The elastohydrodynamic lubrication problem of metal-on-metal hip joint replacements was considered in this study. A simple ball-in-socket configuration was used to represent the hip prosthesis. The Reynolds equation in a spherical coordinate was adopted for the fluid-film lubrication analysis, to account for the ball-in-socket geometry. The corresponding elastic deformation was calculated by means of the finite element method in order to consider the complex ball-in-socket geometry as well as the backing materials underneath the acetabular cup. Both the Reynolds and the elasticity equations were solved simultaneously using the Newton-Raphson finite difference method. The general methodology developed was then applied to a recent experimental prototype metal-on-metal hip implant. It was shown that the backing materials underneath the acetabular cup had little influence on the predicted contact pressure and the elastic deformation at the bearing surfaces for this particular example. Both the film thickness and the hydrodynamic pressure distributions were obtained under various loads up to 2500 N. The predicted minimum lubricating film thickness from the present study was compared with a simple estimation using the Hamrock and Dowson formulae based upon an equivalent ball-on-plane model and excellent agreement was found. However, it was pointed out that for some forms of metal-on-metal hip prostheses with a thin acetabular cup, a polyethylene inlay underneath a metallic bearing insert or a taper connection between a bearing insert and a fixation shell, the general methodology developed in the present study should be used and this will be considered in future studies.

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Suzuki, Katsuji, Kunio Shibata, Kanae Shigemori, Hirofusa Ichinose i Tohru Tanaka. "Arthroplasty Using Ball-and-Socket Type Ceramic Prosthesis for the Osteoarthritis of the Trapeziometacarpal Joint of the Thumb". Key Engineering Materials 309-311 (maj 2006): 1363–66. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.1363.

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Six patients underwent arthroplasty of the trapeziometacarpal joint of the thumb with our ball-and socket type ceramic prosthesis for the osteoarthritis of Eaton stage 3 or 4. Our prosthesis was made of alumina ceramic and high-density polyethylene. Pain and dislocation or subluxation of the trapeziometacarpal joint were found in all of the patients preoperatively and these symptoms were relieved completely after surgery. The % total active motion of the trapeziometacarpal joint and metacarpophalangeal + interphalangeal joints, the % grip strength and % pinch strength improved postoperatively. The trapeziometacarpal joint function according to Eaton’s criteria after surgery was excellent of 5 patients and good of 1 patient.

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Hu, Penghao, Linchao Zhao, Chuxin Tang, Shanlin Liu, Xueming Dang i Yi Hu. "A New Method for Measuring the Rotational Angles of a Precision Spherical Joint Using Eddy Current Sensors". Sensors 20, nr 14 (20.07.2020): 4020. http://dx.doi.org/10.3390/s20144020.

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Precision spherical joint is a spherical motion pair that can realize rotation with three degrees of freedom. This joint is widely used in robots, parallel mechanisms, and high-end medical equipment, as well as in aerospace and other fields. However, the rotation orientation and angle cannot be determined when the joint is in passive motion. The real-time determination of the rotation orientation and angle is crucial to the improvement of the motion control accuracy of the equipment where the joint is installed in. In this study, a new measurement method that utilizes eddy current sensors is proposed to identify the special features of the joint ball and realize angle measurements indirectly. The basic idea is to manufacture the specific shape features on the ball without affecting its movement accuracy and mechanical performance. An eddy current sensor array is distributed in the ball socket. When the ball head rotates, the features on the ball opposite to the sensor, as well as the output signal of every eddy current sensor, change. The measurement model that establishes the relationship between the output signal of the eddy current sensor array and the rotation direction and angle of the ball head is constructed by learning and training an artificial neural network. A prototype is developed using the proposed scheme, and the model simulation and feasibility experiment are subsequently performed. Results show that the root mean square angular error of a single axis within a range of ±14° is approximately 20 min, which suggests the feasibility of the proposed method.

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Kraus, Eric M. "Hearing Results with Clothespin Ossiculoplasty: Preliminary Report on the Kraus Modified Schuring Ossicle-Cup Prosthesis (Clothespin Prosthesis)". Otolaryngology–Head and Neck Surgery 109, nr 1 (lipiec 1993): 26–34. http://dx.doi.org/10.1177/019459989310900105.

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The clothespin partial ossicular replacement prosthesis (PORP) is designed to Increase Joint stability during incus replacement ossiculoplasty. Fundamental modifications have been made in the Schuring ossicle-cup, which include a forked well, increased well wall thickness and length, and a flexible tip disk added to the shaft. The forked well functions like a straight clothespin rather than an inverted cup. The forked well enables the clothespin prothesis to slide down over the stapes superstructure, between the facial nerve canal and the promontory, to form a stable, mortise-and-tenon prosthesis-stapedial joint. Joint stability is enhanced because the inferior tine of the forked well is able to lever against the inferior surface of the stapes superstructure, creating a counterforce to gravity. This is in contrast to the more unstable ball-and-socket joint created by most partial ossicular replacement prostheses when they articulate with the stapes capitulum. The addition of a flexible disk to the shaft tip produces a tight, stable union between the prosthesis and the ossicular cap by increasing resistance at the shaft-ossicle interface. Fluoroplastic composition maximizes Intraoperative versatility and reliability while the ossicle cap minimizes extrusions. One-year hearing results for twelve chronic ear patients with mobile stapes undergoing clothespin ossiculoplasty during intact canal wall tympanomastoidectomy revealed postoperative air-bone gaps within 20 dB in 92% of cases. The mean postoperative air-bone gap was 8.9 dB, and the mean Improvement in air-bone gap was 14.4 dB. These results are attributable to greater prosthesis stability provided by the time-tested mortise-and-tenon joint concept rather than a ball-and-socket joint in a reconstructive situation in which stability is critical.

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Jani, Shilest, Gary Williams, Silvio P. Marchese-Ragona i Briggs Christie. "Using the Atomic Force Microscope to Measure Roughness Characteristics of Acetabular Prosthetic Shells Used as Hip Socket Replacements". Microscopy Today 3, nr 3 (kwiecień 1995): 14–18. http://dx.doi.org/10.1017/s1551929500063215.

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Total replacement of a diseased or traumatized hip joint is fast becoming one of the most common surgical procedures. The acetabular prosthetic shell is gaining widespread acceptance as a socket replacement for this procedure. Bio-materials research is providing a wealth of information regarding the life span, wear characteristics, and performance of these replacements, with a major clinical finding being the destruction of bone (osteolysis) at interfaces with the implants. Osteolysis is widely thought to be associated with the particulate wear debris released from articulation of the ball and socket. Formation and release of these particulates will depend not only on the relative motion occurring but also on the surface roughness of the replacement materials.

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Li, W., S. Wayte, D. Griffin, D. Chetwynd, D. Karampela, E. Torabi i K. Mao. "An Initial Investigation of Hip Joint Contact Behaviour Using Advanced Non-Linear Finite Element Methods". Applied Mechanics and Materials 668-669 (październik 2014): 1557–60. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.1557.

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The hip implant is a very successful treatment for serious osteoarthritis, especially in older patients, but less desirbale for earlier interventions. There is a growing consensus that most hip arthritis is due to shape abnormalities that cause impingement at the ball and socket, collectively called femoroacetabular impingement (FAI). The ball does not fit accurately into the socket, leading to premature wear, and then destructive arthritis. It is not then necessary to replace the whole hip joint; newly developed surgical techniques that accurately reshape the bones to relieve impingement and reduce wear have been shown to be effective. This surgery can be performed with a conventional open approach, or be arthroscopic (keyhole) surgery. It would be better to reshape bones to suit each individual patient. Finite element methods (FEM) have been widely used for biomechanical studies of hip implants and periacetabular osteotomy, but hardly at all in hip reshaping. Non-linear FEM is employed in the current study to perform biomechanical evaluations of differences in contact pressure between normal and arthritic hip joints to help basic understanding and lead to more accurate surgery. The hip joint bone structure is obtained through a medical CT scan and then the CT images have been converted into a format readable by FEM solvers. A sophisticated non-linear contact model of the hip joint bringing together the interactions of true geometry, natural movement and contact forces has been established using this advanced FEM.

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HANSEN, T. B., i D. VAINORIUS. "High Loosening Rate of the Moje Acamo Prosthesis for Treating Osteoarthritis of the Trapeziometacarpal Joint". Journal of Hand Surgery (European Volume) 33, nr 5 (październik 2008): 571–74. http://dx.doi.org/10.1177/1753193408090759.

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The Moje Acamo carpometacarpal (CMC) implant is an uncemented large ball-and-socket joint made of a ceramic material coated with a bioactive substance (Bioverit) for osseous fixation. Nine Moje Acamo CMC prostheses were implanted into nine patients with primary osteoarthritis of the thumb CMC joint. At 12 months, three implants had been revised because of progressing pain and osteolysis. In the remaining six patients, radiographs have shown progressive osteolysis around both implants in five patients. These poor results mean that we no longer perform this operation and we recommend close follow-up of all cases that have been performed.

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Williams, Gary, Shilesh Jani i Silvio P. Marchese-Ragona. "Using the atomic-force microscope to measure roughness characteristics of acetabular prosthetic shells used as hip-socket replacements". Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 470–71. http://dx.doi.org/10.1017/s0424820100170086.

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Total replacement of a diseased or traumatized hip joint is fast becoming one of the most common surgical procedures. The acetabular prosthetic shell is gaining widespread acceptance as a socket replacement for this procedure. Bio-materials research is providing a wealth of information regarding the life span, wear characteristics, and performance of these replacements, with a major clinical finding being the destruction of bone (osteolysis) at interfaces with the implants. Osteolysis is widely thought to be associated with the particulate wear debris released from articulation of the ball and socket. Formation and release of these particulates will depend not only on the relative motion occurring but also the surface roughness of the metal.In this study we used the Atomic Force Microscope (AFM) to compare the internal surface topography of two acetabular shells, one polished to a mirror finish and the other unpolished. The ultimate goal of the study was to determine whether a polished shell reduces the amount of wear and tear on the ultra-high molecular weight polyethylene (UHMWPE) insert that is fitted between the shell and the Femoral ball (Figure 1).

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Xi, Juntong, Xin Hu i Ye Jin. "Shape Analysis and Parameterized Modeling of Hip Joint". Journal of Computing and Information Science in Engineering 3, nr 3 (1.09.2003): 260–65. http://dx.doi.org/10.1115/1.1607353.

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This paper presented a new method of shape analysis of hip joint. The bony surfaces of 12 male hipbone specimens and 26 female hipbone specimens were scanned using a 3D laser scanner. After performing local and global morphology analyses on the acetabulum surface, a rotation ellipsoid CAD model was applied to fit the acetabulum surface, and then an optimization technique was used to find the geometric parameters of the model. This study compared the fitting error between the sphere and rotation ellipsoid. The result is that the fitting error of rotation ellipsoid is smaller than the sphere, and the rotation ellipsoid can describe the shape of the acetabulum better. This shape likely decreases the cases of hip joint subluxation compared to a ball and socket joint.

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Kumar, G., A. Hallet, V. Kamath i S. R. Murali. "An unusual cause of ankle pain: stress fracture in a ball and socket ankle joint". Foot and Ankle Surgery 8, nr 3 (styczeń 2002): 221–22. http://dx.doi.org/10.1046/j.1460-9584.2002.00329.x.

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Ådland, Hans Magne, i Arne Mikkelsen. "Rotational diffusion of two-segmented macromolecules with a ball–socket joint: A kinetic theory approach". Journal of Chemical Physics 118, nr 7 (15.02.2003): 3376–91. http://dx.doi.org/10.1063/1.1537248.

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Loo, Tip W., M. Claire Bartlett i David M. Clarke. "Human P-glycoprotein Contains a Greasy Ball-and-Socket Joint at the Second Transmission Interface". Journal of Biological Chemistry 288, nr 28 (3.06.2013): 20326–33. http://dx.doi.org/10.1074/jbc.m113.484550.

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Wang, W.-Z., F.-C. Wang, Z.-M. Jin, D. Dowson i Y.-Z. Hu. "Numerical lubrication simulation of metal-on-metal artificial hip joint replacements: Ball-in-socket model and ball-on-plane model". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 223, nr 7 (15.04.2009): 1073–82. http://dx.doi.org/10.1243/13506501jet581.

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Barrey, Cédric, Thomas Mosnier, Jérôme Jund, Gilles Perrin i Wafa Skalli. "In vitro evaluation of a ball-and-socket cervical disc prosthesis with cranial geometric center". Journal of Neurosurgery: Spine 11, nr 5 (listopad 2009): 538–46. http://dx.doi.org/10.3171/2009.6.spine0949.

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Object Few biomechanical in vitro studies have reported the effects of disc replacement on motion and kinematics of the cervical spine. The purpose of this study was to analyze motion through 3D load-displacement curves before and after implantation of a ball-and-socket cervical disc prosthesis with cranial geometric center; special focus was placed on coupled motion, which is a well-known aspect of normal cervical spine kinematics. Methods Six human cervical spines were studied. There were 3 male and 3 female cadaveric specimens (mean age at death 68.5 ± 5 years [range 54–74 years]). The specimens were evaluated sequentially in 2 different conditions: first they were tested intact; then the spinal specimens were tested after implantation of a ball-and-socket cervical disc prosthesis, the Discocerv, at the C5–6 level. Pure moment loading was applied in flexion/extension, left and right axial rotation, and left and right lateral bending. All tests were performed under load control with a 3D measurement system. Results No differences were found to be statistically significant after comparison of range of motion between intact and instrumented spines for all loading conditions. The mean range of motion for intact spines was 10.3° in flexion/extension, 5.6° in lateral bending, and 5.4° in axial rotation; that for instrumented spines was 10.4, 5.2, and 4.8°, respectively. No statistical difference was observed for the neutral zone nor stiffness between intact and instrumented spines. Finally, the coupled motions were also preserved during axial rotation and lateral bending, with no significant difference before and after implantation. Conclusions This study demonstrated that, under specific testing conditions, a ball-and-socket joint with cranial geometrical center can restore motion in the 3 planes after discectomy in the cervical spine while maintaining physiological coupled motions during axial rotation and lateral bending.

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Meyer, Donna M., i John A. Tichy. "Lubrication Model of an Artificial Hip Joint: Pressure Profile Versus Inclination Angle of the Acetabular Cup". Journal of Tribology 121, nr 3 (1.07.1999): 492–98. http://dx.doi.org/10.1115/1.2834094.

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Formulation of a three-dimensional, quasi-static lubrication model of an artificial hip joint is proposed which includes the inclination angle of the acetabular cup. This is performed by deriving a transformed Reynolds equation accounting for this cup tilt angle. The numerical simulation also addresses mass conservation at the location of film rupture. A 3-D spherical representation of the articulating surfaces of the hip prosthesis is mapped onto a cartesian coordinate system of the entire geometry of the “ball and socket” joint. Results include the lubricating fluid pressure distributions for various inclination angles of the acetabular cup demonstrating that the greatest pressures occur for large eccentricities in the upward vertical direction.

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Choi, Hyeon Ki, Min Jwa Seo, Ja Choon Koo, Hyeon Chang Choi i Won Hak Cho. "The Effects of Muscle Forces on Ankle Joint Kinetics during Postural Balance Control". Key Engineering Materials 326-328 (grudzień 2006): 871–74. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.871.

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We assessed the effects of muscle forces on ankle joint kinetics during postural balance control of human boy. Nine male subjects (mean age of 25.8 yrs) participated in the experiment. An ankle joint model assumed ball and socket joint was used, which was capable of three dimensional rotations. A six-camera VICON system was used for motion analysis. Waist pulling system and force platform were adopted for forward sway and GRF (ground reaction force) measurement. We used linear optimization programs to calculate the variation of muscle forces and angular displacements of shank and foot segments. With the experimental data and linear programs, we could calculate joint reaction forces, and bone-on-bone forces. The results presented in this study give us the insights to understand the roles of lower limb muscles during postural balance control and ankle injury mechanism.

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LIU, Wenzhi. "Swing Performance Analysis of Rolling Ball Joint Socket Nozzle in a Certain Solid Propellant Rocket Motor". Journal of Mechanical Engineering 49, nr 13 (2013): 93. http://dx.doi.org/10.3901/jme.2013.13.093.

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Kollig, E., W. Weber, D. Bieler i A. Franke. "Failure of an uncemented thumb carpometacarpal joint ceramic prosthesis". Journal of Hand Surgery (European Volume) 42, nr 6 (20.01.2017): 599–604. http://dx.doi.org/10.1177/1753193416688427.

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Thumb carpometacarpal joint replacement is associated with high rates of loosening and failure. We present our results for an uncemented ceramic–ceramic total joint prosthesis with a reverse ball-and-socket design and bioactive coating. Between 2008 and 2012, 29 prostheses were inserted into 28 patients (mean age 63 years) with advanced osteoarthritis. After a mean period of 33 months (range 9–62), 26 patients (27 implants) were available for follow-up. Six months postoperatively, 50% of the patients had radiological evidence of early loosening. Fifteen implants had been removed in 14 patients for aseptic loosening (13) or trapezium fracture (2). The 12 patients whose prosthesis was still in place had a mean visual analogue scale pain score of 1.9 (range 0–6) and a mean Disabilities of the Arm, Shoulder and Hand score of 23 (range 0–73.3). Eleven patients were satisfied with the procedure. The rate of early aseptic failure was unacceptably high. Level of evidence: IV

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Hu, Peng-Hao, Ze-Xun Lu, Yuan-Qi Zhang, Shan-Lin Liu i Xue-Ming Dang. "A New Modeling Method of Angle Measurement for Intelligent Ball Joint Based on BP-RBF Algorithm". Applied Sciences 9, nr 14 (17.07.2019): 2850. http://dx.doi.org/10.3390/app9142850.

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The rotation orientation and the angle of precision of an intelligent ball joint cannot be automatically obtained in passive motion. In this paper, a new method based on a Hall sensor with a permanent magnet (PM) is proposed to identify the spatial rotation orientation and angle. The basic idea is to embed a PM on a ball while the Hall sensors are arrayed into the ball socket. When the ball rotates, the Hall sensor array detects the variation of the magnetic induction intensity in space. By establishing a mathematical model between the variation of the magnetic induction intensity and the orientation and angle of rotation, the rotation angle in the space where the ball is located can be inversely solved. The establishment of the theoretical model is based on the theory of the equivalent magnetic charge method, which has a few native defects that cannot be overcome by itself. This paper presents the relationship between the magnetic induction intensity change and the rotation angle of the ball in space, which was constructed by an artificial neural network (ANN) and will simplify the mathematical model, shorten the operation time, and improve the efficiency of real-time detection. Based on the simulation analysis, the optimal matching scheme between the PM and the magnetic effect sensor was determined, and the structural parameters of the ball joint prototype were optimized. The data training and comparison test of the neural network model were completed on a self-developed calibration device. The experimental results show that for a ±20° measurement range, the average errors of the uniaxial measurements are 1′51″ and 1′55″ on the two axes, respectively. At present, the measurement accuracy of the prototype is still relatively low; however, this idea of modeling based on ANN removes the shackles of mathematical modeling, reminding us that we can consider the design of sensors or complete geometric measurement modeling from a new perspective.

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