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The purpose of this paper is to present a novel automatic planning and coordinated control method of redundant dual‐arm space robot for inner space‐station operation based on multiple sensors information by stages.

In order to improve the coordinated control capability of dual‐arm robot system, a four‐layer hierarchical control structure is designed based on the theory of centralization and decentralization. At the high‐level planning of dual‐arm system, a task decomposition strategy based on task knowledge and a task allocation strategy in terms of the robotic capability are proposed, respectively. Moreover, a control method by stages based on the information of multiple sensors is introduced to object recognition, task planning, path planning and trajectory planning. Finally, a 3D simulation and experiment of screwing nut and bolt are implemented on a dual‐arm robot system, and the feasibility and applicability of this control strategy are verified.

The automatic planning can be accomplished by means of sensors information by stages, and by this method, the autonomy and intelligence of dual‐arm space robot system can be further improved.

A new automatic planning strategy integrated with multiple sensors information by stages is proposed, and can be implemented on a dual‐arm robot system for inner space‐station operations. This method specializes in heterogeneous dual‐arm robot system.

A task decomposition strategy based on task knowledge and a task allocation strategy in terms of the robotic capability are proposed, respectively. Moreover, a control method by stages based on the information of multiple sensors is introduced to object recognition, task planning, path planning and trajectory planning of dual‐arm robot system.

This paper aims to propose a united kinematic calibration method for a dual-machine system in automatic drilling and riveting. The method takes both absolute and relative pose accuracy into account, which will largely influence the machining accuracy of the dual-machine system and assembly quality.

A comprehensive kinematic model of the dual-machine system is established by the superposition of sub-models with pose constraints, which involves base frame parameters, kinematic parameters and tool frame parameters. Based on the kinematic model and the actual pose error data measured by a laser tracker, the parameters of coordinated machines are identified by the Levenberg–Marquardt method as a multi-objective nonlinear optimization problem. The identified parameters of the coordinated machines will be used in the control system.

A new calibration method for the dual-machine system is developed, including a comprehensive kinematic model and an efficient parameter identification method. The experiment results show that with the proposed method, the pose accuracy of the dual-machine system was remarkably improved, especially the relative position and orientation errors.

This method has been used in an aircraft assembly project. The calibrated dual-machine system shows a good performance on system coordination and machining accuracy.

This paper proposes a new method with high accuracy and efficiency for the dual-machine system calibration. The research can be extended to multi-machine and multi-robot fields to improve the system precision.

The purpose of this paper is to analyze the coexistence of independent and manufacturer-owned distributors within the same distribution system. In particular, the authors seek to identify those factors that determine the use of dual distribution and the effect of dual distribution systems on different economic outcomes.

Using a case study-based approach, the authors compare different brands in different European markets of a German automobile manufacturer using 24 expert interviews in Germany, Sweden and Spain.

Our results demonstrate the importance of limited resources, investment specificity, location, divergent interests and competitive strategies for the development of dual distribution structures. The results show that the overall distribution system performance is positively related to dual distribution.

The generalizability of the findings is limited due to the use of cases for different brands of one large corporation within a specific industry and the limited number of countries that were examined. This study is also limited to the subjective evaluation of firm performance and the qualitative evidence provided by the interviewees in our sample group. Our study contributes to the ongoing debate on the use of independent and manufacturer-owned distributors among distributive vertical chains. Based on the qualitative findings, propositions for future research and managerial implications are provided.

While in previous research, the explanatory approach of make-or-buy has often been used for examining dual distribution, the authors combine insights from different theoretical streams (transaction cost theory, market-based view, resource-based view and principal-agent theory) to identify and empirically investigate the antecedents and outcomes of dual distribution. Furthermore, while prior research focused on single-country studies and franchise systems, the authors examine a multi-country sample in the automobile industry and expand the findings of the existing literature by covering different brands.

The purpose of this paper is to present a novel and accurate coordination control method of dual‐arm modular robot based on position feedback using 3D motion measurement system – Optotrak3020. The end‐position accuracy of dual‐arm modular robot can be improved obviously.

By means of Optotrak3020, the actual end‐position of dual‐arm modular robot is acquired and then returned to the robotic controllers, so the corresponding position error compensation is implemented. Through a 3D simulation and experiment of dual‐arm modular robot for tracking a trajectory of plane right triangle, the feasibility and validity of this control strategy are verified.

The coordination control of dual‐arm modular robot based on position feedback can be accomplished by means of Optotrak3020. The dual‐arm modular robot can accurately accomplish the task of positioning or tracking a reference trajectory.

This real‐time position feedback control method with high control accuracy can be implemented on a PowerCube dual‐arm modular robot system. This method also can be applied to other dual‐arm robot systems, such as mobile robot with dual‐arm, humanoid robot.

The coordination control method of dual‐arm modular robot is presented based on end‐position feedback using Optotrak3020 motion measurement system. The platforms of simulation, communication and experiment are developed, respectively.

We describe a novel mathematical approach to deriving and solving covolume models of the incompressible 2‐D Navier‐Stokes flow equations. The approach integrates three technical components into a single modelling algorithm: 1. Automatic Grid Generation. An algorithm is described and used to automatically discretize the flow domain into a Delaunay triangulation and a dual Voronoi polygonal tessellation. 2. Covolume Finite Difference Equation Generation. Three covolume discretizations of the Navier‐Stokes equations are presented. The first scheme conserves mass over triangular control volumes, the second scheme over polygonal control volumes and the third scheme conserves mass over both. Simple consistent finite difference equations are derived in terms of the primitive variables of velocity and pressure. 3. Dual Variable Reduction. A network theoretic technique is used to transform each of the finite difference systems into equivalent systems which are considerably smaller than the original primitive finite difference system.

The existence of clearance in joints of positioning mechanism is inevitable and the movements of the real mechanism are deflected from the ideal mechanism due to the clearances. The purpose of this paper is to investigate the effects of clearance on the dynamic characteristics of dual-axis positioning mechanism of a satellite antenna.

The dynamics analysis of dual-axis positioning mechanism with clearance are investigated using a computational approach based on virtual prototyping technology. The contact model in joint clearance is established by using a hybrid nonlinear continuous contact force model and the friction effect is considered by using a modified Coulomb friction model. Then the numerical simulation of dual-axis positioning mechanism with joint clearance is carried out and four case studies are implemented for different clearance sizes.

Clearance leads to degradation of the dynamic performance of the system. The existence of clearance causes impact dynamic loads, and influences the motion accuracy and stability of the dual-axis positioning mechanism. Larger clearance induces higher frequency shakes and larger shake amplitudes, which will deteriorate positioning accuracy.

Providing an effective and practical method to analyze dynamic characteristics of dual-axis positioning mechanism of satellite antenna with joint clearance and describing the dynamic characteristics of the dual-axis positioning system more realistically, which improves the engineering application.

The paper is the basis of mechanism design, precision analysis and robust control system design of dual-axis positioning mechanism of satellite antenna.

The purpose of this paper is the research of a novel gesture-based dual-robot collaborative interaction interface, which achieves the gesture recognition when both hands overlap. This paper designs a hybrid-sensor gesture recognition platform to detect the both-hand data for dual-robot control.

This paper uses a combination of Leap Motion and PrimeSense in the vertical direction, which detects both-hand data in real time. When there is occlusion between hands, each hand is detected by one of the sensors, and a quaternion-based algorithm is used to realize the conversion of two sensors corresponding to different coordinate systems. When there is no occlusion, the data are fused by a self-adaptive weight fusion algorithm. Then the collision detection algorithm is used to detect the collision between robots to ensure safety. Finally, the data are transmitted to the dual robots.

This interface is implemented on a dual-robot system consisting of two 6-DOF robots. The dual-robot cooperative experiment indicates that the proposed interface is feasible and effective, and it takes less time to operate and has higher interaction efficiency.

A novel gesture-based dual-robot collaborative interface is proposed. It overcomes the problem of gesture occlusion in two-hand interaction with low computational complexity and low equipment cost. The proposed interface can perform a long-term stable tracking of the two-hand gestures even if there is occlusion between the hands. Meanwhile, it reduces the number of hand reset to reduce the operation time. The proposed interface achieves a natural and safe interaction between the human and the dual robot.

This paper aims to critically review the underlying assumptions and theoretical conceptualizations of duality theories in general. In particular, the paper seeks to augment McCabe et al.’s (2016) reconceptualization of consumer decision-making in tourism. Additionally, the paper offers an integrated duality theory model.

A critical discussion of the basic assumptions, recent advances and constructive criticism of duality theories found in the extant literature prefaces a detailed account of McCabe et al.’s (2016) new general tourist choice model. The author enriches and expands the conceptualization of this model and offers an advanced dual-process theoretical framework for decision-making with a broader range of variables, greater versatility, and suggestions for future research.

The findings indicate mental processes with broader external inputs (stimuli) with possible outputs (decisions/behaviors) warrant inclusion and expansion in a fulsome dual-systems model of tourist decision-making.

This research study adds to the literature of duality theories in consumer decision-making. While factors, contexts, personal preferences and other dimensions in the tourism industry are and will continue to be fluid over time, this study offers an integrated decision-making framework that provides clear linkages that mark pathways for new developments, future research and practitioner applications.

The integrated duality theory framework enables researchers and destination management organizations managers to acquire enhanced explanatory and predictive value of tourism decision-making, which can lead to offering improved products/services. The model’s emphasis on simultaneous engagement of both heuristic and analytic dual processes reflects fundamental human nature; decision-making can be “both/and” as well as “either/or” with heuristic and analytic processes.

The purpose of this paper is to check if there is a procyclical lending behaviour in dual banking systems of the Golf Cooperation Council (GCC) countries. The study also tries to control for the role of Islamic banks in amplifying or mitigating the procyclicality of dual banking systems.

Estimation of a dynamic panel model using annual observations on a sample of 81 banks based in the GCC countries between 2005 and 2018. The study uses two business cycle indicators as dependent variables, namely, output gap and oil price gap.

The system generalilzed method of moments (GMM) estimator and robustness checks confirm the procyclical lending pattern of dual banking systems in the GCC. Estimation outputs also indicate that this procyclicality is more pronounced during economic slowdowns. However, it is found that Islamic banks’ lending is less procyclical, giving support for the stability view of Islamic banking systems. The authors think that the implementation and conduct of macroprudential policies are very challenging for banking authorities when Islamic banks and conventional banks operate under the same regulatory framework.

The research paper may suffer from some limitations. Indeed, exploring panel data instead of country-case data may lead to a problem of heterogeneity that may underpin the credibility of the econometrical estimations. To deal with this problem by introducing a set of bank-specific and time-specific dummies. Furthermore, small N samples (N = number of individuals) may affect the reliability of the tests for the validity of instruments and autocorrelation used under the GMM estimator, leading to inefficient results. Consequently, the number of selected banks is extended as much as possible (81 banks), becoming important comparing to the time dimension of the panel.

Policymakers and regulators are incited to embed the perspectives of Islamic finance regarding lending cyclicality in dual banking systems, which promote the efficiency of resource allocation to the financing of assets and by consequence enabling financial stability. The stability view of the Islamic banking system could prompt policymakers and regulators to encourage the implementation and development of Islamic banks.

The present paper tries to overcome the lack of empirical studies on the procyclicality of dual banking. The study contributes to this novel literature in two ways. First, it focuses exclusively on GCC banking systems. In fact, compared to other emerging markets, business cycles characterizing GCC are specific because of the role played by the oil and gas revenues in the economic growth and financial system is crucial. Second, this paper brings into evidence the procyclicality of GCC banking systems also when the oil price is taken as a business cycle indicator.

The purpose of this paper is to present a dual manipulator system for aloft hot-line assembly tasks of connection fittings in 110-kv intelligent substation, which is significant to the research on hot-line working robots.

This paper addresses the challenges of the task and presents a dual manipulator system which can overcome these challenges to realize the robotic assembly of connection fittings in narrow space without impacting the safe distance of both phase to phase and phase to ground. Two manipulators share a same global reference coordinate. The mission of Manipulator 1 is to position the fixed part of connection fittings and screw the bolts on it. Visual computing provides the approximately position for the end-effector of Manipulator 2, after which The Manipulator 2 carries the removable part of connection fittings to this position. Then, the assembly task could be completed with the posture of the Manipulator 2 adjusted following the guidance by force-position control.

The dual manipulator system can position the target under different illumination conditions and complete fast assembly of connect fittings in 110-kV substation. No strong arc discharge or surface erosion phenomenon has been observed.

This dual manipulator system will be particularly useful for the hot-line assembly of connection fittings in 110-kv intelligent substation, as well as some assembly tasks where uncertain target position and complex contact surface such as cylindrical hole is involved.

This study presents a dual manipulator system used by a field robot working in 110-kv intelligent substation. The system is able to achieve the connection fittings assembly task under energized simulation experimental system. Unlike other peg-in-hole assembly strategy, it does not require high stability of manipulator or plane contact surface around the hole.