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This paper aims to present a fully actuated aerial manipulator (AM) with a robust motion/force hybrid controller for conducting contact-typed inspection tasks in industrial plants.

An AM is designed based on a hexarotor with tilted rotors and a rigidly attached end effector. By tilting the rotors, the position and attitude of the AM can be controlled independently, and the AM can actively exert forces on industrial facilities through the rigidly attached end effector. A motion/force hybrid controller is proposed to perform contact-typed inspection tasks. The contact-typed inspection task is divided into the approach phase and the contact phase. In the approach phase, the AM automatically approaches the contact surface. In the contact phase, a motion/force hybrid controller is used for contact-typed inspection. Finally, a disturbance observer (DOB) is used to estimate external disturbances and used as feedforward compensation.

The proposed AM can slowly approach the contact surface without significant impact in the contact phase. It can realize constant force control in the direction normal to the contact surface in the contact phase, whereas the motion of the remaining directions can be controlled by the operator. The use of the DOB ensures the robustness of the AM in the presence of external wind disturbances.

A fully actuated AM system with a robust motion/force hybrid controller is proposed. The effectiveness of the proposed AM system for conducting contact-typed industrial inspection tasks is validated by practical experiments.

The prerequisite for most traditional visual simultaneous localization and mapping (V-SLAM) algorithms is that most objects in the environment should be static or in low-speed locomotion. These algorithms rely on geometric information of the environment and restrict the application scenarios with dynamic objects. Semantic segmentation can be used to extract deep features from images to identify dynamic objects in the real world. Therefore, V-SLAM fused with semantic information can reduce the influence from dynamic objects and achieve higher accuracy. This paper aims to present a new semantic stereo V-SLAM method toward outdoor dynamic environments for more accurate pose estimation.

First, the Deeplabv3+ semantic segmentation model is adopted to recognize semantic information about dynamic objects in the outdoor scenes. Second, an approach that combines prior knowledge to determine the dynamic hierarchy of moveable objects is proposed, which depends on the pixel movement between frames. Finally, a semantic stereo V-SLAM based on ORB-SLAM2 to calculate accurate trajectory in dynamic environments is presented, which selects corresponding feature points on static regions and eliminates useless feature points on dynamic regions.

The proposed method is successfully verified on the public data set KITTI and ZED2 self-collected data set in the real world. The proposed V-SLAM system can extract the semantic information and track feature points steadily in dynamic environments. Absolute pose error and relative pose error are used to evaluate the feasibility of the proposed method. Experimental results show significant improvements in root mean square error and standard deviation error on both the KITTI data set and an unmanned aerial vehicle. That indicates this method can be effectively applied to outdoor environments.

The main contribution of this study is that a new semantic stereo V-SLAM method is proposed with greater robustness and stability, which reduces the impact of moving objects in dynamic scenes.

This paper aims to study the turning strategies for the bounding quadruped robot with an active spine and explore the significant role of the spine in the turning locomotion.

Firstly, the bounding gait combining the pitch motion of the spine with the leg motion is presented. In this gait, the spine moves in phase with the front legs. All the joints of the legs and spine are controlled by cosine signals to simplify the control, and the initial position and oscillation amplitude of the joints can be tuned. To verify the effectiveness of the proposed gait, the spine joints are set with different initial positions and oscillation amplitudes, and the initial position and oscillation amplitude of the leg joints are tuned to make the virtual model do the best locomotion in terms of the speed and stability in the simulation. The control signals are also used to control a real robot called Transleg. Then, three different turning strategies are proposed, including driving the left and right legs with different strides, swaying the spine in the yaw direction and combining the above two methods. Finally, these strategies are tested on the real robot.

The stable bounding locomotion can be achieved using the proposed gait. With the spine motion, the speed of the bounding locomotion is increased; the turning radius is reduced; and the angular velocity is increased.

A simple and flexible planning of the bounding gait and three turning strategies for the bounding quadruped robot are proposed. The effectiveness of the proposed bounding gait, along with the beneficial effect of the spine motion in the yaw direction on the turning locomotion is demonstrated with the computer simulations and robot experiments. This will be instructive for the designing and actuating of the other quadruped robots.

This paper aims to tele-operate the movement of an unmanned aerial vehicle (UAV) in the obstructed environment with asymmetric time-varying delays. A simple passive proportional velocity errors plus damping injection (P-like) controller is proposed to deal with the asymmetric time-varying delays in the aerial teleoperation system.

This paper presents both theoretical and real-time experimental results of the bilateral teleoperation system of a UAV for collision avoidance over the wireless network. First, a position-velocity workspace mapping is used to solve the master-slave kinematic/dynamic dissimilarity. Second, a P-like controller is proposed to ensure the stability of the time-delayed bilateral teleoperation system with asymmetric time-varying delays. The stability is analyzed by the Lyapunov–Krasovskii function and the delay-dependent stability criteria are obtained under linear-matrix-inequalities conditions. Third, a vision-based localization is presented to calibrate the UAV’s pose and provide the relative distance for obstacle avoidance with a high accuracy. Finally, the performance of the teleoperation scheme is evaluated by both human-in-the-loop simulations and real-time experiments where a single UAV flies through the obstructed environment.

Experimental results demonstrate that the teleoperation system can maintain passivity and collision avoidance can be achieved with a high accuracy for asymmetric time-varying delays. Moreover, the operator could tele-sense the force reflection to improve the maneuverability in the aerial teleoperation.

A real-time bilateral teleoperation system of a UAV for collision avoidance is performed in the laboratory. A force and visual interface is designed to provide force and visual feedback of the slave environment to the operator.

Rising expectations for exceptional customer experiences demand strategic amalgamation of cross-functional, customer-focused teams (marketing/sales/service departments). However, the long history of interface conflicts between functional teams continues to attract research attention. Past research has given more attention to conflicts between marketing and sales teams than to triadic interface conflict between custom-focused teams and their sub-conflicts in a business-to-business (B2B) sales process. The purpose of this research paper is to quantify the triadic interface conflicts and associated sub-conflicts between customer-focused teams, discuss conflict resolution strategies and perform a sensitivity analysis (SA) to give a fuller account of functional team conflict.

Multi-criteria decision-making (MCDM) based in the analytic hierarchy process (AHP) is proposed for identifying and resolving conflicts in customer-focused team interfaces. A group of 30 managers of a large electronics company participated in this research. The authors collected the data from customer-focused team managers during training sessions on interface conflicts and conflict management/resolution strategies. The authors perform SA to test the robustness of conflict resolution strategy rankings.

The findings reveal that managers adjudge task as the most crucial conflict attribute driving teams apart, followed by lack of communication. For the sub-conflicts, managers considered how to do the task as the most important conflict attribute, followed by lack of regular meetings. For conflict resolution strategies, managers regarded collaboration or integration as the overall best strategy, followed by compromise. Leveraging the AHP-based MCDM to resolve customer-focused team interface conflicts provides managers with the confidence in the consistency and the robustness of these solutions. By testing the SA, it is also discovered that the final outcome stayed robust (stable) regardless when the priorities of the main criteria influencing the decision are increased and decreased by 5% in every combinations.

This study examined only a large B2B company in the electronics industry in African and Middle East settings, focusing on interface conflicts among customer-focused departments. Future research could address these limitations.

This paper advances our understanding of customer-focused team interface conflicts in a B2B sales process. It also provides valuable insights on effective management of major and sub-interface conflicts. This paper provides a framework for and practical insights into how interface conflicts that are prevalent in marketing, sales and service sectors can be resolved to improve customer experience and business performance.

This study contributes to the literature by developing an AHP-based MCDM, which not only extends our conceptual understanding of the interface conflicts between customer-focused teams by emphasizing their triadic nature but also provides valuable strategies and insights into the practical resolution of such conflicts in a B2B firm’s sales process. Methodologically, SA is valuable to ensuring the robustness of the conflict resolution strategies’ rankings that will influence relevant pragmatic decision-making.

This paper aims to develop an efficient algorithm combining straightforward response surface functions with Monte Carlo simulation to conduct seismic reliability analysis in a systematical way.

The representative slip surfaces are identified and based on to calibrate multiple response surface functions with acceptable accuracy. The calibrated response surfaces are used to determine the yield acceleration in Newmark sliding displacement analysis. Then, the displacement-based limit state function is adopted to conduct seismic reliability analysis.

The calibrated response surface functions have fairly good accuracy in predicting the yield acceleration in Newmark sliding displacement analysis. The seismic reliability is influenced by such factors as PGA, spatial variability and threshold value. The proposed methodology serves as an effective tool for geotechnical practitioners.

The multiple sources of a seismic slope response can be effectively determined using the multiple response surface functions, which are easily implemented within geotechnical engineering.

Sliding wear is a common phenomenon in the iron ore handling industry. Large-scale handling of iron ore bulk-solids causes a high amount of volume loss from the surfaces of bulk-solids-handling equipment. Predicting the sliding wear volume from equipment surfaces is beneficial for efficient maintenance of worn equipment. Recently, the discrete element method (DEM) simulations have been utilised to predict the wear by bulk-solids. However, the sensitivity of wear prediction subjected to DEM parameters has not been systemically investigated at single particle level. To ensure the wear predictions by DEM are accurate and stable, this study aims to conduct the sensitivity analysis at the single particle level.

In this research, pin-on-disc wear tests are modelled to predict the sliding wear by individual iron ore particles. The Hertz–Mindlin (no slip) contact model is implemented to simulate interactions between particle (pin) and geometry (disc). To quantify the wear from geometry surface, a sliding wear equation derived from Archard’s wear model is adopted in the DEM simulations. The accuracy of the pin-on-disc wear test simulation is assessed by comparing the predicted wear volume with that of the theoretical calculation. The stability is evaluated by repetitive tests of a reference case. At the steady-state wear, the sensitivity analysis is done by predicting sliding wear volumes using the parameter values determined by iron ore-handling conditions. This research is carried out using the software EDEM^® 2.7.1.

Numerical errors occur when a particle passes a joint side of geometry meshes. However, this influence is negligible compared to total wear volume of a wear revolution. A reference case study demonstrates that accurate and stable results of sliding wear volume can be achieved. For the sliding wear at steady state, increasing particle density or radius causes more wear, whereas, by contrast, particle Poisson’s ratio, particle shear modulus, geometry mesh size, rotating speed, coefficient of restitution and time step have no impact on wear volume. As expected, increasing indentation force results in a proportional increase. For maintaining wear characteristic and reducing simulation time, the geometry mesh size is recommended. To further reduce simulation time, it is inappropriate using lower particle shear modulus. However, the maximum time step can be increased to 187% T_R without compromising simulation accuracy.

The applied coefficient of sliding wear is determined based on theoretical and experimental studies of a spherical head of iron ore particle. To predict realistic volume loss in the iron ore-handling industry, this coefficient should be experimentally determined by taking into account the non-spherical shapes of iron ore particles.

The effects of DEM parameters on sliding wear are revealed, enabling the selections of adequate values to predict sliding wear in the iron ore-handling industry.

The accuracy and stability to predict sliding wear by using EDEM^® 2.7.1 are verified. Besides, this research accelerates the calibration of sliding wear prediction by DEM.

The aim of this paper is to expand the knowledge of buyer‐supplier relationships by investigating the extent to which organisational cultural fit between a buyer and supply chain participants influences performance.

The study was conducted in a FMCG supply chain. A cultural dimensions questionnaire was used in a focal organisation (the buyer) and it identified best and poorest performing supply chain. The results were analysed using a series of ANOVA's within the respective supply chains. The findings were then triangulated via qualitative methods.

The findings demonstrate that complementarity rather than congruence between the supply chain partners achieved successful performance outcomes. Organisations in the high‐performing supply chain had significantly different cultural profiles, reporting significant statistical differences across all six cultural dimensions. Organisations in the low‐performing supply chain had almost identical profiles across all six cultural dimensions with significantly lower mean scores across each dimension.

The deconstruction of organisational culture into its constituent dimensions in a supply chain provides insights for academics. Propositions are presented which provide a platform for further studies. Future studies could develop these findings by using a larger sample, over a longer period of time, and adding mediating variables that impact supply chain outcomes.

Managers should pay attention to cultural evaluation within the supplier selection process as well as finance or strategic evaluations. A shared supply chain culture of norm‐based trust and openness may yield better outcomes and reduced conflict and uncertainty throughout the supply chain.

This is one of the first papers to deconstruct and measure organisational cultural fit empirically in a supply chain context.

This paper aims to explore how firms enter or exit B Corp certification faced with the tension between local and B Corp institutions, providing a better understanding of the unique impact of institutional complexity on B Corps' decision-making.

This paper applies multi-case analysis to 20 Chinese firms in various stages of B Corp certification, including eight certified B Corps, six decertified firms and six candidates. The qualitative data was used to code separately for two research questions.

The study findings reveal that: (1) Participants who can obtain expected social and economic benefits by innovating their operational mode to efficiently deal with this tension attempt to continuously pursue B Corp certification. A self-renewal model was developed to show how firms hybridize the two institutional logics; (2) Participants who find it hard to mitigate this tension tend to compromise with the local institution and conform less with the B Corp institution due to high opportunity and accounting costs, low short-term benefits and collective culture.

By highlighting the different responses of firms to institutional complexity, this study contributes to B Corp research, social identity theory and institutional complexity, providing practical implications for B Lab strategies in China.

The purpose of this study is to propose the generalised integral transform technique to investigate the natural convection behaviour in a vertical cylinder under different boundary conditions, adiabatic and isothermal walls and various aspect ratios.

GITT was used to investigate the steady-state natural convection behaviour in a vertical cylinder with internal uniformed heat generation. The governing equations of natural convection were transferred to a set of ordinary differential equations by using the GITT methodology. The coefficients of the ODEs were determined by the integration of the eigenfunction of the auxiliary eigenvalue problems in the present natural convection problem. The ordinary differential equations were solved numerically by using the DBVPFD subroutine from the IMSL numerical library. The convergence was achieved reasonably by using low truncation orders.

GITT is a powerful computational tool to explain the convection phenomena in the cylindrical cavity. The convergence analysis shows that the hybrid analytical–numerical technique (GITT) has a good convergence performance in relatively low truncation orders in the stream-function and temperature fields. The effect of the Rayleigh number and aspect ratio on the natural convection behaviour under adiabatic and isothermal boundary conditions has been discussed in detail.

The present hybrid analytical–numerical methodology can be extended to solve various convection problems with more involved nonlinearities. It exhibits potential application to solve the convection problem in the nuclear, oil and gas industries.