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The design of the space hatch door mechanisms is crucial in the aerospace field, impacting not only durability and reliability but also the life safety of astronauts during space missions. This review extensively researches vehicle doors and hatches in civil and military systems across various environments, including land, sea, deep sea, aviation, aerospace, and extreme conditions. Specially, it focuses on the structural design of hatches and related mechanisms in civil aviation and military aerospace environments, such as opening and closing mechanisms, release mechanisms, locking mechanisms, sealing mechanisms, and the ergonomic design of door structures. The review highlights the integration of bionic design principles with hatch mechanisms to explore future solutions. By systematically examining these aeras, this review addresses the lack of comprehensive studies in previous reviews, which often overlook the interconnectivity and applicability of hatch mechanisms across different fields. The absence of such holistic reviews has led to fragmented knowledge and missed opportunities for cross-industry innovation. This review aims to fill these gaps by providing a wide range of design solutions and offering insights that can enhance the development of more reliable, efficient, and safe hatch mechanisms in aerospace and other high-stakes environments. [ABSTRACT FROM AUTHOR]

The deployable telescopic boom, whose mass and stiffness play crucial roles, is extensively used in the design of space-deployable structures. However, the most existing optimal design that neglects the influence of the locking mechanisms in boom joints cannot raise the whole stiffness while reducing the boom mass. To tackle this challenge, a novel optimization model, which utilizes the arrangement of the locking mechanisms to achieve synchronous improvement of the stiffness and mass, is proposed. The proposed optimization model incorporates a novel joint stiffness model developed based on an equivalent parallel mechanism that enables the consideration of multiple internal stiffness factors of the locking mechanisms and tubes, resulting in more accurate representations of the joint stiffness behavior. Comparative analysis shows that the proposed stiffness model achieves more than at least 11% improved accuracy compared with existing models. Furthermore, case verification shows that the proposed optimization model can improve stiffness while effectively reducing mass, and it is applied in boom optimization design. [ABSTRACT FROM AUTHOR]

The design of the space hatch door mechanisms is crucial in the aerospace field, impacting not only durability and reliability but also the life safety of astronauts during space missions. This review extensively researches vehicle doors and hatches in civil and military systems across various environments, including land, sea, deep sea, aviation, aerospace, and extreme conditions. Specially, it focuses on the structural design of hatches and related mechanisms in civil aviation and military aerospace environments, such as opening and closing mechanisms, release mechanisms, locking mechanisms, sealing mechanisms, and the ergonomic design of door structures. The review highlights the integration of bionic design principles with hatch mechanisms to explore future solutions. By systematically examining these aeras, this review addresses the lack of comprehensive studies in previous reviews, which often overlook the interconnectivity and applicability of hatch mechanisms across different fields. The absence of such holistic reviews has led to fragmented knowledge and missed opportunities for cross-industry innovation. This review aims to fill these gaps by providing a wide range of design solutions and offering insights that can enhance the development of more reliable, efficient, and safe hatch mechanisms in aerospace and other high-stakes environments.

Shape morphing is the ability of objects to adapt to different shapes and reduce stress concentrations through increased contact area. This is a common trait of natural and engineered objects and has several applications in, among others, soft robotics and orthopedic implants. Shape morphing is achieved through flexible materials or rigid components with either kinematic or compliant joints. An additional step, namely shape locking, is needed for sustained load support. Activation of a locking mechanism can be done with any energy, among which magnetism is one. Here, we present the implementation of a magnetic locking mechanism for kinematically deformable metamaterial structures that maintain shape and support loads upon locking. The structure consists of 3D printed rigid magnetic and non-magnetic components connected by hinges. We created several prototypes of the proposed designs using two additive manufacturing methods (i.e., material extrusion and multi-material jetting) and demonstrated its application in a closed-loop grid for arbitrary shapes. Moreover, we characterized the performance of the prototypes using mechanical tests and multibody kinematic system simulations. This work highlights the viability of the locking concept and provides design considerations for future applications. Further improvement and optimizations are needed for increased efficiency and effectiveness.

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There are various techniques used for tendon lengthening, of which Z-lengthening and sliding-lengthening are the most frequently performed. In patients with cerebral palsy, tendon lengthening may often be necessary at multiple sites. However, they can cause various complications, such as inaccurate extension, overextension, and a lack of tendon continuity. We modified the sliding-lengthening technique with a locking mechanism to address these issues. This technical note aims to describe the surgical technique and pitfalls associated with the modified sliding-lengthening approach and suture locking mechanism. The tendon was exposed and stabilized using sterilized spitz tubes and was then threaded so that each loop length was equivalent to the amount of tendon extension. Symmetrical hemisection of both ends of the tendon was performed, and the tendon was carefully extended to create a tense loop. The modified sliding-lengthening technique with the locking suture mechanism may be an advantageous method that accurately addresses extension volume, prevents hyperextension, and maintains tendon continuity, even when smaller incisions are used. [ABSTRACT FROM AUTHOR]

Traditional feet robots have shortcomings of mechanism flexibility insufficient in adaptive walking on complex terrain. A bio-tensegrity foot mechanism is proposed for promoting the performance of adaptive terrain and stable locking locomotion of the conventional foot robots on sloped terrain based on the similarity between musculoskeletal systems and a tensegrity structure. The equivalent mapping model of a tensegrity structure is established by the matching of tension unit，the design of configuration of the mechanism achieved by the method of bionic design，a physical sample is made and an experimental platform is built. The results show that the proposed bionic foot mechanism has good flexibility and stability，the adaptive and stable walking ability of the traditional foot robot on slope terrain are improved.

Smartphone technology can be applied not only to establish communication needs but also to support other purposes. One of them is related to personal safety and security functions. It is undeniable that criminal acts can occur anytime and anywhere. Even in a private or residential area, theft could happen. Smartphone and sensor technology can be used as a solution to encounter this problem. In this case, it can be utilized to improve the security control system of the gate or garage door at home. This research presents a prototype of a gate and garage door control and security system that operates through an application on an android smartphone. The application of HC-05 Bluetooth is used to send signals from the smartphone to the Arduino Uno microcontroller, while the micro servo acts as a locking mechanism on the gate itself. The buzzer function is presented to notify homeowners when the gate or garage door is open for more than 15 seconds. This prototype can control gates and garage doors with an average connection time of only about 5 seconds. Thus, this prototype is feasible to use as an alternative to control and improve housing security systems.

Arthroplasty implants are comprised of metal alloys designed to function within the human body. Implant-related issues and associated soft-tissue reactions have been well documented for modular revision hip and knee constructs. This case highlights findings of metallosis in the context of polyethylene wear in a failed primary total knee arthroplasty. Fretting of a polyethylene reinforcement pin within the tibial baseplate as a direct result of knee joint instability appears to be the root cause of observed periprosthetic metallosis. Enhanced design principles and improved polyethylene locking mechanisms may be useful to potentially mitigate fretting-related issues in future knee replacement designs. The authors recommend surveillance in patients with this construct especially when prosthetic instability is present.

The paper presents an interlocking system designed to fix and hold together the panels of a modular house. The house modules are flat square panels, almost identical, which need to be hold using a locking system. The locking system is a simple, but solid construction, capable to resist to repeated assembling and disassembling operations. It consists of some linkage mechanisms and a ratchet; it is hand-powered in order to ensure a fast mounting of the panels. In this paper are presented all the steps necessary to be followed and the restraints of the design process.

The paper presents an interlocking system designed to fix and hold together the panels of a modular house. The house modules are flat square panels, almost identical, which need to be hold using a locking system. The locking system is a simple, but solid construction, capable to resist to repeated assembling and disassembling operations. It consists of some linkage mechanisms and a ratchet; it is handpowered in order to ensure a fast mounting of the panels. In this paper are presented all the steps necessary to be followed and the restraints of the design process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Tiangong University is the property of Journal of Tianjin Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Development of the diagnostic rack and the locking mechanism for the ITER vacuum vessel lower port. • Addressing manufacturability issues and adapting to the ITER environment. • Accommodating a wide range of reaction forces and improving positioning repeatability. • Feasibility of the design considering manufacturability and uncertainties, thanks to its robustness. The development of the diagnostic rack and the locking mechanism, to be placed in the ITER vacuum vessel's lower port, are in progress. This paper presents the details of these development activities. This paper addresses solving manufacturability issues encountered in previous designs on the diagnostic rack and confirming the validity of the locking mechanism in the ITER environment. The locking mechanism must generate reaction forces to lock the diagnostic rack in the lower port by bending a beam structure, considering robustness, is determined using thermal-structural analysis. The range of the reaction forces, that the locking mechanism can accommodate considering variation due to loads, interface structure, and uncertainties such as frictions are broad, approximately 150 kN–325 kN via 3–7 mm bending displacement of the beam structure. Subsequently, a mock-up of the locking mechanism was manufactured and tested to assess reaction force and positioning repeatability, which is necessary for ensuring diagnostic measurements. The reaction forces were balanced with assumptions of uncertainties, such as friction force and positioning misalignment. The positioning repeatability was improved while increasing the reaction force, the positioning repeatability is 0.49 mm as the two standard deviations (2σ) while satisfying a requirement of +/- 1 mm. We conclude that the design is validated, even when considering realistic manufacturability and uncertainties such as friction and dimensional measurement accuracy, due to the locking mechanism's robust design. [ABSTRACT FROM AUTHOR]

We hereby present a rare case of pharyngocutaneous fistula associated with locking screw loosening causing internal cricopharynx perforation and Horner's syndrome following anterior cervical plating. A 27-year-old male patient had undergone anterior cervical plating at C5--C7 level due to gunshot injury to the neck, and 1 month postsurgery, he developed fistula in the neck showing discharge of consumed food contents. He presented to us 1 year postsurgery with the discharging fistula, left upper-limb weakness, and Horner's syndrome that developed after surgery. The previously unexplored right side was used to remove implant, and owing to solid union at corpectomy, no additional fixation was performed. Intraoperatively, pharyngeal wall dehiscence was observed. Attempt of removal of impinged screw was abandoned since it migrated into the esophagus. Serial abdomen radiographs revealed successive passage of screw through the gastrointestinal (GI) tract until it could not be visualized. As the patient showed reduced discharge, a GI surgeon gave a conservative trial with nasogastric intubation. Currently, fistula is showing minimal discharge with no food. Having knowledge of this possible rare outcome and awareness of various multidisciplinary approaches for management makes practicing spine surgeon equipped to handle such undesirable complications. [ABSTRACT FROM AUTHOR]

A Hyperledger Fabric is a popular permissioned blockchain platform and has great commercial application prospects. However, the limited transaction throughput of Hyperledger Fabric hampers its performance, especially when transactions with concurrency conflicts are initiated. In this paper, we focus on transactions with concurrency conflicts and propose solutions to optimize the performance of Hyperledger Fabric. Firstly, we propose a novel method LMLS to improve the Write-Write Conflict. This method introduces a lock mechanism in the transaction flow to enable some conflicting transactions to be marked at the beginning of the transaction process. And indexes are added to conflicting transactions to optimize the storage of the ledger. Secondly, we propose a cache-based method to improve the Read-Write Conflict. The cache is used to speed up reading data, and a cache log is added to Hyperledger Fabric to ensure the data consistency. Extensive experiments demonstrate that the proposed novel methods can significantly increase transaction throughput in the case of concurrency conflicts, and maintain high efficiency in transactions without concurrency conflicts. [ABSTRACT FROM AUTHOR]

For precision enhancement, many robotic systems for minimally invasive surgery (MIS) have been developed. However, a positioning arm that firmly fixes the initial position of surgical robot arm has not been researched in depth yet. Since a positioning arm is a device for positioning a surgical robots, it should be equipped with a robust locking mechanism against external force. Furthermore, as repositioning of the surgical robot occurs frequently before and during the operation, the positioning arm needs a mechanism to lock and unlock multi-degrees-of-freedom (MDoF) simultaneously to reduce the setup time. Therefore, we propose a novel MDoF locking mechanism applicable to a positioning arm for MIS. When the knob of the locking mechanism is rotated, the two joints are locked simultaneously by the movement of the friction pad and the locking block that is mounted inside the positioning arm. Considering the locking time and the locking torque, the design parameters of the locking mechanism were determined to be optimal. The proposed locking mechanism was implemented and verified on a positioning arm for MIS. The first experimental results showed that only the negligible clearance between the joints was generated during the locking and unlocking transition. These indicate that positioning of the surgical robot is precise when the proposed mechanism is applied. The second experimental results showed that the proposed locking mechanism has a higher performance than the conventional locking device, in terms of locking torque. These indicate that the proposed locking mechanism will enhance safety in a surgical environment. [ABSTRACT FROM AUTHOR]

Highly cross‐linked, ultrahigh molecular weight polyethylene (HXLPE) acetabular liners are inherently associated to a risk of fatigue failure due to femoral neck impingement. Different thicknesses and designs employed with HXLPE liners greatly affect mechanical loading scenario. The purpose of this study was to clarify the influence of liner offset (lateralization) and locking mechanism (presence/absence of anti‐rotation tabs in the external surface) on fatigue durability in annealed and vitamin E‐blended HXLPE liners with a current commercial design. Each liner tested had six anti‐rotation tabs, which were engaged in the 6 of 12 recesses on the metal shell. The remaining six recesses had no direct contact with the liner, where HXLPE was mechanically unsupported by the metal backing. These mated and/or unmated rim regions in the offset (2, 3, 4‐mm lateralized) liners were exposed to severe neck impingement until crack propagation was identified. Phase volume percentages (crystalline, amorphous, and intermediate phase contents) of HXLPE liners were compared before and after impingement in order to interpret differences in impingement micromechanics associated with the rim design variations. Our results showed that the presence of unmated recesses served as a stress concentrator due to the formation of millimeter‐scale gaps between the liner and shell. Another potential design problem drawn from our study was liner offset associated with a small volume protruding above the metal rim. Therefore, surgeons should take special care in selecting locking designs and geometries especially when using HXLPE offset liners. [ABSTRACT FROM AUTHOR]

Ｉｎ ｏｒｄｅｒ ｔｏ ｒｅｄｕｃｅ ｔｈｅ ｎｕｍｂｅｒ ｏｆ ｍｅｃｈａｎｉｓｍ ｔｒｉａｌｓ ａｎｄ ｌａｔｃｈｉｎｇ ｆｏｒｃｅ ｔｅｓｔｓ ｄｕｒｉｎｇ ｔｈｅ ｃｏｎｖｅｎｔｉｏｎａｌ ｄｅｓｉｇｎ ｐｒｏｃｅｓｓ ｏｆ ｔｈｅ ｒｏｃｋｅｔ ｇｕｎ ｌｏｃｋｉｎｇ ｍｅｃｈａｎｉｓｍꎬ ｔｈｅ ｆａｃｔｏｒｓ ａｆｆｅｃｔｉｎｇ ｔｈｅ ｃｈａｎｇｅ ｏｆ ｔｈｅ ｌｏｃｋｉｎｇ ｆｏｒｃｅ ｂｅｔｗｅｅｎ ｔｈｅ ｈｏｏｋ ａｎｄ ｔｈｅ ｒｏｃｋｅｔ ｃｏｎｔａｃｔ ｓｕｒｆａｃｅ ｆｒｉｃｔｉｏｎ ｃｏｅｆｆｉｃｉｅｎｔꎬ ｄｉｆｆｅｒｅｎｔ ｌｏａｄｉｎｇ ｌｏａｄｓ ａｎｄ ｄｉｆｆｅｒｅｎｔ ｍａｓｓ ｒｏｃｋｅｔｓ ｄｕｒｉｎｇ ｔｈｅ ｄｅｃｏｕｐｌｉｎｇ ｐｒｏｃｅｓｓ ｗｅｒｅ ｃａｒｒｉｅｄ ｏｕｔ. Ｔｈｅ Ａｂａｑｕｓ/ Ｅｘｐｌｉｃｉｔ ｗａｓ ｕｓｅｄ ｔｏ ｄｉｓｐｌａｙ ｔｈｅ ｎｏｎｌｉｎｅａｒ ｄｙｎａｍｉｃ ａｎａｌｙｓｉｓ ｍｅｔｈｏｄꎬ ｔｈｅ ｄｅｃｏｕｐｌｉｎｇ ｐｒｏｃｅｓｓ ｏｆ ｔｈｅ ｌｏｃｋｉｎｇ ｍｅｃｈａｎｉｓｍ ｈｏｏｋ ｏｆ ａ ｒｏｃｋｅｔ ｄｕｒｉｎｇ ｔｈｅ ｌａｕｎｃｈｉｎｇ ｐｒｏｃｅｓｓ ｗａｓ ｓｉｍｕｌａｔｅｄ. Ｔｈｅ ｗｏｒｋｉｎｇ ｍｅｃｈａｎｉｓｍ ｏｆ ｔｈｅ ｌｏｃｋｉｎｇ ｍｅｃｈａｎｉｓｍ ｗａｓ ｓｔｕｄｉｅｄꎬ ｗｈｉｃｈ ａｆｆｅｃｔｅｄ ｔｈｅ ｌｏｃｋｉｎｇ ｍｅｃｈａｎｉｓｍ ｉｎ ｔｈｅ ｗｏｒｋｉｎｇ ｐｒｏｃｅｓｓ. Ｔｈｅ ｆａｃｔｏｒｓ ａｆｆｅｃｔｉｎｇ ｔｈｅ ｂｌｏｃｋｉｎｇ ｆｏｒｃｅ ｗｅｒｅ ｑｕａｎｔｉｔａｔｉｖｅｌｙ ａｎａｌｙｚｅｄ. Ｔｈｅ ｒｅｓｕｌｔｓ ｓｈｏｗ ｔｈａｔ ｗｈｅｎ ｔｈｅ ｍａｓｓ ｏｆ ｔｈｅ ｐｒｏｊｅｃｔｉｌｅ ｉｎｃｒｅａｓｅｓ ｂｙ ５０％ꎬ ｔｈｅ ｄｅｃｏｕｐｌｉｎｇ ｔｉｍｅ ａｎｄ ｔｈｅ ｂｌｏｃｋｉｎｇ ｆｏｒｃｅ ｉｎｃｒｅａｓｅ ｂｙ ａｂｏｕｔ １３. ４％. Ｂｙ ｃｏｍｐａｒｉｎｇ ｔｈｅ ｅｘｐｅｒｉｍｅｎｔａｌ ｄａｔａ ｏｆ ｔｈｅ ｐｒｏｊｅｃｔｉｌｅ ｑｕａｌｉｔｙ ａｎｄ ｔｈｅ ｓｉｍｕ￣ ｌａｔｉｏｎ ｒｅｓｕｌｔｓꎬ ｔｈｅ ｓｉｍｕｌａｔｉｏｎ ａｎａｌｙｓｉｓ ｓｈｏｗｓ ｔｈａｔ ｔｈｅ ｅｒｒｏｒ ｂｅｔｗｅｅｎ ｔｈｅ ｓｉｍｕｌａｔｉｏｎ ａｎａｌｙｓｉｓ ａｎｄ ｔｈｅ ａｃｔｕａｌ ｓｉｔｕａｔｉｏｎ ｉｓ １. ５％ꎬ ｔｈｅ ｅｒｒｏｒ ｉｓ ｓｍａｌｌꎬ ａｎｄ ｔｈｅ ｃｒｅｄｉｂｉｌｉｔｙ ｉｓ ｈｉｇｈ. [ABSTRACT FROM AUTHOR]

[Display omitted] • A shape-morphing and shape-locking structure was fabricated by additive manufacturing. • A component printed from magnetic composite material supplied activation by magnetism. • Kinematic simulation and mechanical tests provided insight in the preferred design for maintaining the locked state. • The viability of a locking concept and considerations on locking concepts in general were shown. Shape morphing is the ability of objects to adapt to different shapes and reduce stress concentrations through increased contact area. This is a common trait of natural and engineered objects and has several applications in, among others, soft robotics and orthopedic implants. Shape morphing is achieved through flexible materials or rigid components with either kinematic or compliant joints. An additional step, namely shape locking, is needed for sustained load support. Activation of a locking mechanism can be done with any energy, among which magnetism is one. Here, we present the implementation of a magnetic locking mechanism for kinematically deformable metamaterial structures that maintain shape and support loads upon locking. The structure consists of 3D printed rigid magnetic and non-magnetic components connected by hinges. We created several prototypes of the proposed designs using two additive manufacturing methods (i.e., material extrusion and multi-material jetting) and demonstrated its application in a closed-loop grid for arbitrary shapes. Moreover, we characterized the performance of the prototypes using mechanical tests and multibody kinematic system simulations. This work highlights the viability of the locking concept and provides design considerations for future applications. Further improvement and optimizations are needed for increased efficiency and effectiveness. [ABSTRACT FROM AUTHOR]

Train run-throughs on railway switches is a special issue, where a train passes through non-trailable railway switches in the wrong direction. This has the potential to cause severe damage and can lead to derailment. In order to understand the impact of train run-throughs on railway switches, a three-dimensional finite element model using explicit analysis has been developed. A detailed switch model has been developed that includes all key components: stretcher bars, supplementary drive and point operating equipment. The model was validated through a specifically designed experiment where switch run-throughs were emulated on a real switch; a good agreement was found between the experimental data and the model. The model has been used to make an assessment of the locking mechanisms. The forces in each component have been assessed and investigated, and the observations of failure location and component during run-through analysis are indicated. During a run-through, the supplementary drive rod and stretcher bar encounter a significant plastic deformation, and it is recommended that they should be redesigned in order to avoid plastic behaviour. [ABSTRACT FROM AUTHOR]

Highlights • The operculum of water snail is a multilayered disk. • The operculum edge has relatively large deformation in locking state. • A model was proposed to evaluate the mechanical properties of operculum. • The bio-inspired structure can remarkably reduce leakage rate. Abstract How can a water snail lock its door by an operculum? In this theoretical and experimental combined research, we revealed this by dissection, modeling and validation with a 3D printed technique. The operculum is a corneous or calcareous trapdoor-like sheet which attaches to the upper surface of the water snail's foot. It can plug the shell aperture by retracting the soft body when a predator or environmental threat is encountered. For a water snail (Pomacea canaliculata), the operculum can be locked in its shell rapidly. By optical microscope images, we found the operculum of P. canaliculata is a multilayered disk with a thicker center and thinner edge, which may be functionally influential for successful closing and opening the trapdoor. We filmed the locking in opercula of living snails, and designed an experiment to measure the deformation of opercula on the dead samples. We propose one mathematical model to describe the connections among geometry, sectionalized stiffness and the force for locking. By using 3D printing technique, we designed an operculum inspired locking mechanism to validate the theories we proposed. Under the same normal force, the water leakage rate of the bio-inspired structure can be reduced to 99% compared to the disk with uniform thickness. Our results reveal that the snail's operculum not only develops a light-weight trapdoor, but a locking mechanism which could serve as a valuable model for designing compliant locking mechanisms. [ABSTRACT FROM AUTHOR]

"Laparoscopist's thumb," or thenar paresthesia, can result from prolonged or excessive grip force during laparoscopy, as can more general syndromes, such as carpal tunnel syndrome. This is particularly relevant in gynecology, where laparoscopic procedures are standard. Although this method of injury is well known, there is a paucity of data to guide surgeons in selecting more efficient, ergonomic instruments. This study compared the ratio of applied tissue force and required surgeon input in a sample of common ratcheting laparoscopic graspers in a small-handed surgeon, to provide potential metrics applicable to surgical ergonomics and surgeon instrument choice. Laparoscopic graspers with varied ratcheting mechanisms and tip shapes were evaluated. Brands included Snowden-Pencer, Covidien, Aesculap, and Ethicon. A Kocher was used as an open instrument comparison. Flexiforce A401 thin-film force sensors were used to measure applied forces. Data were collected and calibrated using an Arduino Uno microcontroller board with Arduino and MATLAB software. Single-handed, complete closure of each device's ratcheting mechanism was performed 3 times. The maximum required input force in Newtons was recorded and averaged. The average output force was measured with a bare sensor and the same sensor between 2 different thicknesses of LifeLike BioTissue. The most ergonomic ratcheting grasper for a small-handed surgeon was identified by the output ratio: the highest output force relative to the required surgeon input (the most force for the least amount of effort). The Kocher required an average input force of 33.66 N, with its highest output ratio of 3.46 (112 N output). The Covidien Endo Grasp was the most ergonomic, with an output ratio of 0.96 on the bare force sensor (31.4 N output). The Snowden-Pencer Wavy grasper was the least ergonomic, with an output ratio of 0.06 when applied to the bare force sensor (5.9 N output). All graspers except for the Endo Grasp had improving output ratios as tissue thickness and subsequent grasper contact area increased. Input force above that provided by the ratcheting mechanisms did not increase output force in a clinically relevant amount for any of the instruments evaluated. Laparoscopic graspers vary widely in their ability to provide reliable tissue force without requiring excessive input by the surgeon, and a point of diminishing returns often exists with increased surgeon input over designed ratcheting mechanisms. Output force and output ratio are potential quantitative measures of the efficiency of laparoscopic instruments. Providing users with this type of data could assist in optimizing instrument ergonomics. [ABSTRACT FROM AUTHOR]

• The new Locking Mechanism (LM) of Diagnostic Rack (DR) in ITER has been developed. • The LM provides superior repeatability and simpler Remote Handling operation. • The LM generates greatest reaction force with minimal preload in previous types. • The LM can possibly be adaptable for various industries and applications. The development of the Locking Mechanism (LM) for the Diagnostic Rack, to be placed in the Lower Port of the ITER Vacuum Vessel, has been underway. This paper proposes a new type of LM due to the feasibility issues in positioning repeatability and Remote Handling (RH) compatibility encountered with previous types. Each LM type was compared based on its ability to generate the largest possible reaction force with the smallest preload, which is necessary for the LM to maintain contact with interface structures. We confirmed that the new LM type could generate the greatest reaction force among the three types, with the smallest preload and assumed attributes of superior repeatability and simpler RH operation. [ABSTRACT FROM AUTHOR]

According to the stochastic distribution of parameters,the reliability analysis of spring locking mechanism is carried out for helical spring by using probability theory and mathematical statistics. The optimization model of the locking mechanism spring parameters is established. Using Simulated Annealing Algorithm（ SAA）,the optimal parameters of spring are provided with the help of computer program compiled with Visual Basic language. The rationality of optimization result is verified by simulation results of the finite element model.

Headspace is a typical assembly requirement in automatic weapon assembly, which directly affects the performance and safety of automatic weapon. To research the headspace under actual working condition, a calculation method of part deformation based on finite element analysis is put forward, and an analysis model of assembly tolerance considering deformation is established. For the assembly accuracy of machine gun with locking lug shifting, an analysis model for locking mechanism is established, the assembly precision change of headspace in considering deformation caused by temperature is analyzed, and the influence of temperature on headspace is studied. The influence of deformation on headspace in counter-recoil and the influence of part deformation during the launching process are investigated. The results show that the distribution center of headspace is obviously offset, and the distribution range contracts with the increase in temperature after considering the deformation induced by temperature. The headspace is decreased by 0.015 mm in considering deformation at barrel chamber temperature of 300~600 ℃. Considering the deformation caused by the impact in counter-recoil, the headspace is increased by 0.02 mm. Elastic deformation of parts is 0.14 mm during the launch process. The transverse fracture of cartridge case will not happen when headspace is between 0.38~0.47 mm, but, will occur when headspace is 0.47~0.48 mm. [ABSTRACT FROM AUTHOR]

Purpose: We have used Modular Universal Tumor and Revision System (MUTARS) tumor prosthesis to reconstruct segmental resection defect of the distal femur. The purpose of this study was to evaluate the incidence and pattern of locking mechanism breakage and its correlation with other clinical variables. Materials and Methods: We retrospectively reviewed 94 patients who were followed-up for more than one year after tumor prosthesis replacement (MUTARS) between 2008 and 2013. We examined the incidence and timing of locking mechanism (PEEK-OPTIMA) failure. We also evaluated the clinical characteristics of patients experiencing locking mechanism failure and compared them with those of other patients. Results: At a mean follow-up of 55 months, we observed locking mechanism failure in 10 of 94 patients (10.6%). The mean age of patients with locking mechanism failure was 29 years (range, 13-54 years); the mean weight and height were 169 cm (range, 151-181 cm) and 67 kg (range, 53-89 kg), respectively. The mean body mass index was 23.5 kg/m2 (range, 20.5-29.4 kg/m2). The median time interval between replacement and locking mechanism failure was 26.5 months (range, 12-72 months). The mean body weight of patients with failure was higher than that of patients without failure (p=0.019). Conclusion: The incidence of locking mechanism (PEEK-OPTIMA) failure after distal femoral reconstruction with MUTARS was 11%, and there was a correlation between failure and body weight of patients. Advancements in the design and material of locking mechanisms are warranted to reduce the complication. [ABSTRACT FROM AUTHOR]

Aiming at structural design problems of suspension cushion on locking mechanism which used in light truck cab, the finite element analysis which applied to design of rub suspension cushion was investigated. After the analysis of carrying out theoretical designs and experimental measurements, the relationship of result between finite element analysis and experimental measurements was established. A method was presented to test the center of mass parameters with static balance method. The design method of suspension cushion for locking mechanism used in light truck cab were evaluated on the center of mass parameters test. Finite element analysis, experimental measurements, static stiffness were tested in the laboratory, the difference between finite element analysis and experimental measurements was constrasted. The results indicate that the difference is less than 10% between static stiffness of suspension cushion and theoretical calculation which used the finite element analysis, which is within acceptable range theoretically, and show that the finite element analysis can be used as a tool to design suspension cushion on locking mechanism which used in light truck cab. [ABSTRACT FROM AUTHOR]

Rice production is distributed broadly in China. The rice growing environment conditions are different in different regions, so there is large difference in rice transplanting spacing. Even in the same growing area, the rice transplanting density and the planting spacing are different due to the difference of the transplanting rice species and the growing conditions. The wide-narrow row planting is beneficial to the field management, which can effectively use the field marginal effects, improve the performance of air and light, and enhance the plant photosynthesis. The microclimate in the field is changed to reduce the humidity between plants, and the pests and diseases of rice. Considering the diversity of rice species and the conditions of soil, water and fertilizer, the conventional transplanter which had fixed row spacing, including the constant row spacing transplanter and the wide-narrow row spacing transplanter, could not meet the rice spacing requirements and caused the low adaptability and the low efficiency. For overcoming above shortcomings together with considering the quality of mechanized transplanting and the agronomic requirements of rice, a spacing-adjustable wide-narrow row high speed rice transplanter, which could transplant the rice seedlings with wide row spacing of 300 mm and adjustable narrow row spacing in the range of 200-300 mm, was designed creatively by using the technology of multi-body dynamics, multidisciplinary design optimization, virtual prototyping and simulation. The force analysis of seeding box, supporting beam and screw shaft was carried out to achieve their reasonable structures. The transplanting spacing of this machine was adjustable according to the requirements of specific rice planting density. The machine could meet the agronomic requirements of rice planting spacing in the different regions, and achieved the full potential of individual strain and rice population and improved the adaptation scope and use efficiency. The rice tranplanter was developed based on the Kubota SPU68C high speed rice transplanter. The key structural parameters of the machine were determined according to the adjustable spacing performance requirements. A coaxial forward and reverse double-helix adjusting mechanism, an eccentric locking mechanism, a separable combination seeding box and other key parts were designed and manufactured. According to the agronomic requirements of mechanized transplanting technology for different rice species, the single cropping mid-season rice species Xinliangyou 98 and the double cropping late rice species Zhendao 18 were chosen as test materials, the field experiments were carried out with the prototype of spacing-adjustable wide-narrow row high speed rice transplanter, and the transplanting seedling quality and the machine performance were studied. Field test results showed that the machine performance was pretty good, the damaged rate of seedling was less than 2.5%, the leakage transplanting rate was less than 3%, the qualified rate of relative uniformity degree was more than 96%, the floating rate of seedling was less than 2.5%, the overturning rate of seedling was less than 2.5%, and the acceptance rate of planting depth was more than 92%, which met the Criteria of Rice Transplanter Technical Conditions (GB/T 20864-2007). The good actual yield results were also achieved with planting the single cropping mid-season rice species Xinliangyou 98 with wide row spacing of 300 mm and narrow row spacing of 250 mm, and the double cropping late rice species Zhendao 18 with wide row spacing of 300 mm and narrow row spacing of 200 mm. The effect of transplanting spacing on the yield of the double cropping late rice is larger than that on the single cropping mid-season rice. The machine has changed the conventional mechanical rice transplanting method. It meets the actual rice production requirements in different regions, effectively solves the problems of the transplanter with fixed spacing which is difficult to meet the diversity of rice species and growing environments, improves the adaptability and the efficiency of machine, and raises the productivity and the mechanization level of rice production. [ABSTRACT FROM AUTHOR]