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The purpose of this paper is to present a novel hybrid pre-tension mechanism for continuum manipulators to prevent wire slack and improve continuum robot payload capacity, as well as to present a new method to control continuum manipulators’ shape.

This research explains the hardware design of a hybrid pre-tension mechanism device and proposes a mathematic formulation wire-tension based on robot design. Also, the wire-tension control method and payload estimation model would be discussed.

Wire-tension is directly related to the continuum manipulators’ rigidity and accuracy. However, in the case of robot motion, wires lose their tension and such an issue leads to the inaccuracy and twist deformation. Therefore, the proposed design assists in preventing any wire slack and derailing the problem of the wires.

The novelty of this research is proposed pre-tension mechanism device design and control schematics. Proposed pre-tension mechanism designed to maintain up to eight wires simultaneously.

The paper explores coordination practices in digital–physical product development and their consequences for companies traditionally relying on physical product development.

Using an embedded case study design, the paper reports four action research initiatives addressing the digital–physical coordination challenges encountered by a leading B2C company.

Effective coordination of digital–physical product development, firstly, involves standardization of process, output and skills to accommodate the stability needed for efficient physical product development and manufacturing. Secondly, it involves agile coordination events, such as Scrum ceremonies and PI planning, to facilitate the mutual adjustment needed to allow agility and the differences between digital and physical product development to be continuously and successfully negotiated.

The paper illustrates a research model with case evidence and suggests tentative theory in the form of propositions. Future research should explore coordination problems and solutions in different digital–physical project types and contexts.

Coordination practices for digital–physical product development are presented and analyzed, providing inspiration for companies.

The paper is the first to explore coordination practices within the emerging field of digital–physical product development.

Slim and dexterous manipulators with long reaches can perform various exploration and inspection tasks in confined spaces. This paper aims to present the development of such a dexterous continuum manipulator for potential applications in the aviation industry.

Benefiting from a newly conceived dual continuum mechanism and the improved actuation scheme, this paper proposes a design of a slim and dexterous continuum manipulator. Kinematics modeling, simulation-based dimension synthesis, structural constructions and system descriptions are elaborated.

Experimental validations show that the constructed prototype possesses the desired dexterity to navigate through confined spaces with its kinematics calibrated and actuation compensation implemented. The continuum manipulator with different deployed tools (e.g. graspers and welding guns) would be able to perform inspections and other tasks at remote locations in constrained environments.

The current construction of the continuum manipulator possesses quite some friction inside its structure. The bending discrepancy caused by friction could accumulate to an obvious level. It is desired to further reduce the friction, even though the actuation compensation had been implemented.

The constructed continuum manipulator could perform inspection and other tasks in confined spaces, acting as an active multi-functional endoscopic platform. Such a device could greatly facilitate routine tasks in the aviation industry, such as guided assembling, inspection and maintenance.

The originality and values of this paper mainly lay on the design, modeling, construction and experimental validations of the slim and dexterous continuum manipulator for the desired mobility and functionality in confined spaces.

There is an increasing popularity for the continuum robot in minimally invasive surgery owing to its compliance and dexterity. However, the dexterity takes the challenges in loading and precise control because of the absence of the shape tracking for the continuum robot. The purpose of this paper is to propose a new type of continuum manipulator with variable stiffness that can track the bending shape timely.

The low-melting-point alloy (LMPA) is used to implement the stiffness variation and shape detection for the continuum manipulator. A conceptual design for a single module is presented, and the principle of stiffness control based on the established static model is formulated. Afterward, a shape detection method is introduced in which the shape of the continuum manipulator can be detected by measuring the resistance of every LMPA. Finally, the effect of the proposed variable stiffness method is verified by simulation; the variable stiffness and shape detection methods are evaluated by experiments.

The results from the simulations and experiments indicate that the designed continuum manipulator has the ability of stiffness variation over 42.3% and the shape detection method has high precision.

Compared with conventional structures, the novel manipulator has a simpler structure and integrates the stiffness variation and shape detection capabilities with the LMPA. The proposed method is promising, and it can be conveniently extended to other continuum manipulators.

Pick-and-place tasks are common across many industrial sectors, and many rigid-linked robots have been proposed for this application. This paper aims to alternatively present the development of a continuum robot for low-load medium-speed pick-and-place tasks.

An inversion of a previously proposed dual continuum mechanism, as a key design element, was used to realize the horizontal movements of the CurviPicker’s end effector. A flexible shaft was inserted to realize rotation and translation about a vertical axis. The design concept, kinematics, system descriptions and proof-of-concept experimental characterizations are elaborated.

Experimental characterizations show that the CurviPicker can achieve satisfactory accuracy after motion calibration. The CurviPicker is easy to control due to its simple kinematics, while its structural compliance makes it safe to work with, as well as less sensitive to possible target picking position errors to avoid damaging itself or the to-be-picked objects.

The vertical translation of the CurviPicker is currently realized by moving the flexible shaft. Insertion of the flexible shaft introduces possible disturbances. It is desired to explore other form of variations to use structural deformation to realize the vertical translation.

The proposed CurviPicker realizes the Schöenflies motions via a simple structure. Such a robot can be used to increase robot presence and automation in small businesses for low-load medium-speed pick-and-place tasks.

To the best of the authors’ knowledge, the CurviPicker is the first continuum robot designed and constructed for pick-and-place tasks. The originality stems from the concept, kinematics, development and proof-of-concept experimental characterizations of the CurviPicker.

The unstable dynamic propagation of multistage hydrofracturing fractures leads to uneven development of the fracture network and research on the mechanism controlling this phenomenon indicates that the stress shadow effects around the fractures are the main mechanism causing this behaviour. Further studies and simulations of the stress shadow effects are necessary to understand the controlling mechanism and evaluate the fracturing effect.

In the process of stress-dependent unstable dynamic propagation of fractures, there are both continuous stress fields and discontinuous fractures; therefore, in order to study the stress-dependent unstable dynamic propagation of multistage fracture networks, a series of continuum-discontinuum numerical methods and models are reviewed, including the well-developed extended finite element method, displacement discontinuity method, boundary element method and finite element-discrete element method.

The superposition of the surrounding stress field during fracture propagation causes different degrees of stress shadow effects between fractures and the main controlling factors of stress shadow effects are fracture initiation sequence, perforation cluster spacing and well spacing. The perforation cluster spacing varies with the initiation sequence, resulting in different stress shadow effects between fractures; for example, the smaller the perforation cluster spacing and well spacing are, the stronger the stress shadow effects are and the more seriously the fracture propagation inhibition arises. Moreover, as the spacing of perforation clusters and well spacing increases, the stress shadow effects decrease and the fracture propagation follows an almost straight pattern. In addition, the computed results of the dynamic distribution of stress-dependent unstable dynamic propagation of fractures under different stress fields are summarised.

A state-of-art review of stress shadow effects and continuum-discontinuum methods for stress-dependent unstable dynamic propagation of multiple hydraulic fractures are well summarized and analysed. This paper can provide a reference for those engaged in the research of unstable dynamic propagation of multiple hydraulic structures and have a comprehensive grasp of the research in this field.

The purpose of this paper is to provide an overview of the design and experimental work of compliant wing and wingtip morphing devices conducted within the EU FP7 project NOVEMOR and to demonstrate that the optimization tools developed can be used to synthesize compliant morphing devices.

The compliant morphing devices were “designed-through-optimization”, with the optimization algorithms including Simplex optimization for composite compliant skin design, aerodynamic shape optimization able to take into account the structural behaviour of the morphing skin, continuum-based and load path representation topology optimization methods and multi-objective optimization coupled with genetic algorithm for compliant internal substructure design. Low-speed subsonic wind tunnel testing was performed as an effective means of demonstrating proof-of-concept.

It was found that the optimization tools could be successfully implemented in the manufacture and testing stage. Preliminary insight into the performance of the compliant structure has been made during the first wind tunnel tests.

The tools in this work further the development of morphing structures, which when implemented in aircraft have potential implications to environmentally friendlier aircrafts.

The key innovations in this paper include the development of a composite skin optimization tool for the design of highly 3D morphing wings and its ensuing manufacture process; the development of a continuum-based topology optimization tool for shape control design of compliant mechanisms considering the stiffness and displacement functions; the use of a superelastic material for the compliant mechanism; and wind tunnel validation of morphing wing devices based on compliant structure technology.

The purpose of this study is to explore the optimum design of bending plate compliant mechanisms subjected to pure mechanical excitations using topological-derivative-based topology optimization. The main objective is to design the reinforcement in a plate of base material.

The optimum design is performed by means of a level-set representation method guided by topological derivatives. Kirchhoff and Reissner–Mindlin models are used to solve the linear bending plate problem. A qualitative comparison has been carried out between the optimal obtained topologies for each model.

The proposed methodology was able to design reinforcement in a plate of the base material. The obtained reinforcements notably improve the device’s behavior. The shape and topology of the reinforcements vary depending on the mechanical plate model considered. In fact, in the Reissner–Mindlin solutions, very thin flexo-torsional hinges connecting big zones of the reinforcement material are designed.

Up to date, the synthesis of ortho-planar mechanisms by means of continuum topology optimization was only boarded within a multi-physics context. In this work, the optimal design of pure ortho-planar compliance actuators is addressed. The best performance is found by analyzing the results for two classical mechanical plate models.

This paper aims to unpack the organization of an multinational enterprise (MNE) and confront its meso‐level complexity of structures and strategies. It seeks to uncover how the glocalization process unfolds, which are the mechanisms at its base and the outcomes in terms of stability, convergence or divergence in strategies and structures.

Through a case study research design, the paper investigates strategic change in an Italian MNE from 2005 to 2011. In 2008 and 2010, extensive data on organizational configurations were also collected. Overall, the paper analyses the glocalized blending of corporate and subsidiary strategies and organizational structures. Attention is also paid to the cognitive, political and institutional mechanisms that accounted for this process before and during the late‐2000 financial crisis.

Glocalization, largely interpreted as an in‐between process compromising between homogeneous global standards and heterogeneous local traditions, unfolds as a beyond process leading to divergent outcomes outside the poles of an imagined local‐global continuum. The mechanisms driving strategic change partly differ from those usually described in strategic change literature emphasizing managerial cognition. Sensegiving from the center is found to be proactive during economic expansion and reactive during economic downturn. Following change initiation, cognitive mechanisms are “taken over” by political and institutional ones. Paradoxically, local societal‐specific patterns of organization and strategy were preserved due to the actions of powerful central HQ actors.

A theory of institutional‐bound strategic change within MNEs is outlined.

The purpose of this paper is to present a novel stretch-retractable single section (SRSS) continuum manipulator which owns three degrees of freedom and higher motion range in three-dimension workspace than regular single continuum manipulator. Moreover, the motion accuracy was analyzed based on the kinematic model. In addition, the experiments were carried out for validation of the theory.

A kinematics model of the SRSS continuum manipulator is presented for analysis on bending, rotating and retracting in its workspace. To discuss the motion accuracy of the SRSS continuum manipulator, the dexterity theory was introduced based on the decomposing of the Jacobian matrix. In addition, the accuracy of motion is estimated based on the inverse kinematics and dexterity theory. To verify the presented theory, the motion of free end was tracked by an electromagnetic positioning system. According to the comparison of experimental value and theoretical analysis, the free end error of SRSS continuum manipulator is less than 6.24 per cent in the region with favorable dexterity.

This paper presents a new stretch-retractable continuum manipulator that the structure was composed of several springs as the backbone. Thus, the SRSS continuum manipulator could own wide motion range depending on its retractable structure. Then, the motion accuracy character of the SRSS continuum manipulator in the different regions of its workspace was obtained both theoretically and experimentally. The results show that the high accuracy region distributes in the vicinity of the outer boundary of the workspace. The motion accuracy gradually decreases with the motion position approaching to the center of its workspace.

The presented SRSS continuum manipulator owns three degrees of freedom. The future work would be focused on the two-section structure which will own six degrees of freedom.

In this study, the SRSS continuum manipulator could be extended to six degrees of freedom continuum robot with two sections that is less one section than regular six degrees of freedom with three single section continuum manipulator.

The value of this study is to propose a SRSS continuum manipulator which owns three degrees of freedom and could stretch and retract to expend workspace, for which the accuracy in different regions of the workspace was analyzed and validated based on the kinematics model and experiments. The results could be feasible to plan the motion space of the SRSS continuum manipulator for keeping in suitable accuracy region.