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The purpose of this paper is to investigate the process of fused filament fabrication (FFF) of a compliant gripper (CG) using thermoplastic polyurethane (TPU) material. The paper studies the applicability of different CG designs and the efficiency of some design parameters.

After reviewing a number of different papers, two designs were selected for a number of exploratory experiments. Using design of experiments (DOE) techniques to identify important design parameters. Finally, the efficiency of the parts was investigated.

The research finds that a simpler design sacrifices some effectiveness in exchange for a remarkable decrease in production cost. Decreasing infill percentage of previous designs and 3D printing them, out of TPU, experimenting with different parameters yields functional products. Moreover, the paper identified some key parameters for further optimization attempts of such prototypes.

The cost of conducting FFF experiments for TPU increases dramatically with product size, number of parameters studied and the number of experiments. Therefore, all three of these factors had to be kept at a minimum. Further confirmatory experiments encouraged.

This paper addresses an identified need to investigate applications of FFF and TPU in manufacturing functional efficient flexible mechanisms, grippers specifically. While most research focused on designing for increased performance, some research lacks discussion on design philosophy, as well as manufacturing issues. As the needs for flexible grippers vary from high-performance grippers to lower performance grippers created for specific functions/conditions, some effectiveness can be sacrificed to reduce cost, reduce complexity and improve applicability in different robotic assemblies and environments.

Fully-actuated unmanned aerial vehicles (UAVs) are a growing and promising field of research, which shows advantages for aerial physical interaction. The purpose of this paper is to construct a force sensor-denied control method for a fully-actuated hexarotor to conduct aerial interaction with accurate force exerted outward.

First, by extending single-dimension impedance model to the fully-actuated UAV model, an impedance controller is designed for compliant UAV pose/force control. Then, to estimate the interaction force between UAV end-effector and external environment accurately, combined with super-twisting theory, a nonlinear force observer is constructed. Finally, based on impedance controller and estimated force from observer, an interaction force regulation method is proposed.

The presented nonlinear observer-based impedance control approach is validated in both simulation and environments, in which the authors try to use a fully-actuated hexarotor to accomplish the task of aerial physical interaction finding that a specified force is able to be exerted to environment without any information from force sensors.

A solution of aerial physical interaction for UAV system enabling accurate force exerted outward without any force sensors is proposed in this paper.

In this study, we explored factors driving evidence-based management (EBM) decision-making in Poland which has experienced changes from state-controlled market environments to more competitive ones. Evidence-based management requires the critical use and adaptability to information to deal with complex problems.

In total, 422 Polish managers responded to a telephone survey measuring their perceptions about decision-making culture, styles, competence, and their use of specific sources to derive the evidence to enable them to make evidence-based decisions. Informed by theoretical principles, we used Hayes’ PROCESS macro (Model 4) to examine whether each factor produced direct effects on EBM decision-making and the mediating influence of competence and style in the relationship between culture and perceived evidence-based decision-making.

All three factors correlated positively with perceived evidence-based decision-making. Moreover, style was not predictive of EBM decision-making compared to competence and culture while culture had an imposing effect on decision-making both as a direct effect and indirectly through competence.

This study provides important insights into the perceptual state of EBM among Polish managers. It emphasizes the importance of embracing diverse cultures and improving critical thinking to help managers make more evidence-based decisions during significant changes in the business world.

As the demand for human–robot collaboration in manufacturing applications grows, the necessity for collision detection functions in robots becomes increasingly paramount for safety. Hence, this paper aims to improve the existing method to achieve efficient, accurate and sensitive robot collision detection.

The external torque is estimated by momentum observers based on the robot dynamics model. Because the state of the joints is more accessible to distinguish under the action of the suppression operator proposed in this paper, the mutated external torque caused by joint reversal can be accurately attenuated. Finally, time series analysis (TSA) methods can continuously generate dynamic thresholds based on external torques.

Compared with the collision detection method based only on TSA, the invalid time of the proposed method is less during joint reversal. Although the soft-collision detection accuracy of this method is lower than that of the symmetric threshold method, it is superior in terms of detection delay and has a higher hard-collision detection accuracy.

Owing to the mutated external torque caused by joint reversal, which seriously affects the stability of time series models, the collision detection method based only on TSA cannot detect continuously. The consequences are disastrous if the robot collides with people or the environment during joint reversal. After multiple experimental verifications, the proposed method still exhibits detection capabilities during joint reversal and can implement real-time collision detection. Therefore, it is suitable for various engineering applications.

Harmonic drives are used widely in aviation, robotics and instrumentation due to their benefits including high transmission ratio, compact structure and zero backlash. One of the common faults of a harmonic drive is the axial movement of the input shaft. In such a case, its input shaft moves in the axial direction relative to the body of the harmonic drive. The purpose of this study is to propose two fault diagnosis methods based on the current signal of the driving servomotor for the axial movement failure in terms of input shafts of harmonic drives.

In the two proposed fault diagnosis methods, the wavelet threshold algorithm is firstly used for filtering noises of the motor current signal. Then, the feature of the denoised current signal is extracted by the empirical mode decomposition (EMD) method and the wavelet packet energy-entropy (WPEE) theory, respectively, obtaining two kinds of feature sets. After a deep learning model based on the deep belief network (DBN) is constructed and trained by using these feature sets, we finally identify the normal harmonic drives and the ones with the axial movement fault.

In contrast to the traditional back propagation (BP) neural network model and support vector machine (SVM) model, the fault diagnosis methods based on the combination of the EMD (as well as the WPEE) and the DBN model can obtain higher accuracy rates of fault diagnosis for axial movement of harmonic drives, which can be greater than or equal to 97% based on the data of the performed experiment.

The authors propose two fault diagnosis methods based on the current signal of the driving servomotor for the axial movement failure in terms of input shafts of harmonic drives, which are verified by the experiment. The presented study may be beneficial for the development of self-diagnosis and self-repair systems of different robots and precision machines using harmonic drives.

Recent technological advancements, often linked to Industry 4.0, require organizations to be more agile and innovative. Blockchain technology (BT) holds immense potential in driving organizations to achieve efficiency and transparency in supply chains. However, there exist some insurmountable challenges associated with the adoption of BT in organizational supply chains (SC). This paper attempts to categorically identify and systematize the most influential challenges in the implementation of BT in SC.

This study resorts to an extensive literature review and consultations with experts in the field of supply chain management (SCM), information technology and academia to identify, categorize and prioritize the major challenges using VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) and Combined Compromise Solution method (CoCoSo).

The top three classes of challenges revealed in this study are privacy challenges (PC), infrastructure challenges (IC) and transparency challenges (TC). Maintaining a balance between data openness and secrecy and rectification of incorrect/erroneous input are the top two challenges in the PC category, integration of BT with sustainable practices and ensuring legitimacy are the top two challenges in the IC category, and proper and correct information sharing in organizations was the top most challenge in the TC category.

Future scholars and industry professionals will be guided by the importance of the challenges identified in this study to develop an economical and logical approach for integrating BT to increase the efficiency and outcome of supply chains across several industrial sectors.

Pupil ‘voice’ is heralded as a key tenet of education policy, practice and research; however, ensuring that voice is authentically heard in the spaces that children occupy remains a challenge. Models of participation – relating to the degree of power either shared or transferred – range from tokenistic approaches to true pupil–teacher partnerships in which pupils initiate ideas and share decision-making with adults. Shier’s (2001) five-step Pathway to Participation model is considered and practitioners are invited to reflect on their own position and identify necessary steps to increase pupil involvement in their local setting. For guidance, a philosophy club intervention for early years and primary-age children is presented as a real-world example of facilitating voice on both group and individual levels. This chapter argues the case for schools to genuinely embrace and utilise pupil voice as part of a whole-school approach to enhance mental health and wellbeing within learning communities.

This study aims to show the complexities of engagement between students - Venezuelan and Brazilian - and their teachers. This qualitative ethnographic study documents the everyday pedagogies and practices that take place in elementary schools with high levels of refugee and immigrant children. While Brazilian law ensures the basic right to public education, forbidding discrimination based on nationality or immigration status (Lei de Diretrizes e Bases da Educação, 1996), the barriers remain. Through the frameworks of multicultural (USA) and intercultural (Brazil) education, this paper shows how Brazilian teachers and students of Venezuelan and Brazilian backgrounds engage, learn from one another and build welcoming spaces, but also how stereotypes are reinforced inside classrooms and schools.

This qualitative study uses ethnography to understand how recent Venezuelan migratory flow influences Brazilian and Venezuelan children’s educational experiences in elementary education. Participants were Venezuelan (N = 57) and Brazilian (N = 76) children in two elementary schools in the city of Boa Vista. Data sources for the study are school observations in four elementary classrooms (1st and 2nd grade) and semi-structured interviews with caregivers, teachers, administrators and other educators. This paper also collected children’s drawings and writings and documents like curricula, strategic planning, guidelines, policies, grades, reports and any other textual or photographic material made available at the city level.

In the field of education, there is a critical need for understanding children’s education experiences. This paper focuses on the experiences of teachers and students in two elementary schools in Brazil. This paper focus on two findings: first that teachers promote the learning of Portuguese to show care toward their Venezuelan students. Second, children in the classroom show solidarity with one another and resist some of the more rigid Portuguese-only practices enacted by teachers. This work uses the frameworks of intercultural (more commonly used in Brazil) and multicultural education to inform the analysis.

In this study, this paper puts these frameworks of interculturalism, multiculturalism, language use and solidarity into conversation to understand the dynamics of two elementary classrooms in the city of Boa Vista, Brazil. While this paper shows the shortcomings of a seemingly multicultural and multilanguage classroom, it also shows how children actively resist the rigidity of teaching and learning in elementary schooling.

This study is a response both to the increasing South–South migration trend in Latin America and its consequences on public education systems. Through multicultural and intercultural lenses, this research highlighted the complexity of interactions within multicultural classrooms by delving into a two-year ethnographic study conducted in Boa Vista, Brazil, focusing on Venezuelan and Brazilian children in two local elementary schools. This paper focused on two main observations this paper refers to as “Teaching Portuguese as a Way of Caring” and “Children's Solidarity Work.” Teachers primarily centered their instruction on teaching Portuguese to migrant children, believing it to lead to quicker integration in the classroom and beyond – thus as a way of caring for their migrant students.

This study aims to formulate a user-friendly pre-design model that could be a decision support tool for green wall systems to assist designers in selecting an optimal green wall system aligned with specified performance criteria while concurrently addressing project requirements linked to social and economic parameters. This approach seeks to enhance overall project satisfaction for the designer and the owner.

A correlation between the green wall context and design requirements and its performance on the buildings have been defined by considering its social and economic parameters, which represented the owner preferences to ensure the most satisfaction from installation as it achieves the required performance that is defined by the designer such as maximizing thermal insulation, improving indoor air quality, reducing the needed heating and cooling loads, etc. and also to achieve the satisfaction in social and economic requirements defined by the owner such as system installation cost, system maintenance cost, adding beauty value, etc.

The research developed an easy pre-design model to be a tool for green wall system decision-making for the most suitable system, which contains three main steps: the first one is defining the required performance of the green wall (designer requirements), the second step is limiting the context of the project which is made by designer and the owner requirements and finally the third step is choosing the system components that ensures achieving the requirements of both owners and designer, related to the building and climate context.

The added value lies in developing a green wall decision-making tool, essentially a pre-design model. This model considers the correlation between the project’s context, encompassing climate and building conditions. It provides a structured approach for decision-making in the early stages of green wall design. It offers valuable insights into the optimal choices related to system type, installation methods and plant characteristics. This enhanced decision-making tool contributes to more informed and efficient design processes, considering each project’s specific needs and conditions.

The present numerical investigation examines the magnetohydrodynamic (MHD) double diffusion natural convection of power-law non-Newtonian nano-encapsulated phase change materials (NEPCMs) in a trapezoidal cavity.

The governing Navier-Stokes, energy and concentration equations based on the Cartesian curvilinear coordinates are solved using the collocated grid arrangement’s finite volume method. The in-house FORTRAN code is validated with the different benchmark problems. The NEPCM nanoparticles consist of a core-shell structure with Phase Change Material (PCM) at the core. The enclosure, shaped as a trapezoidal hollow, features a warmed (T_h) left wall and a cold (T_c) right wall. Various parameters are considered, including the power law index (0.6 ≤ n ≤ 1.4), Hartmann number (0 ≤ Ha ≤ 30), Rayleigh number (10⁴ ≤ Ra ≤ 10⁵) and fixed variables such as buoyancy ratio (Br = 0.8), Prandtl number (Pr = 6.2), Lewis number (Le = 5), fusion temperature (Θ_f = 0.5) and volume fraction (ϕ = 0.04).

The findings indicate a decrease in local Nusselt (Nu) and Sherwood (Sh) numbers with increasing Hartmann numbers (Ha). Additionally, for a shear-thinning fluid (n = 0.6) results in the maximum local Nu and Sh values. As the Rayleigh number (Ra) increases from 10⁴ to 10⁵, the structured vortex in the streamline pattern is disturbed. Furthermore, for different Ra values, an increase in n from 0.6 to 1.4 leads to a 67.43% to 76.88% decrease in average Nu and a 70% to 77% decrease in average Sh.

This research is for two-dimensioal laminar flow only.

PCMs represent a class of practical substances that behave as a function of temperature and have the innate ability to absorb, release and store heated energy in the form of hidden fusion enthalpy, or heat. They are valuable in these systems as they can store significant energy at a relatively constant temperature through their latent heat phase change.

As per the literature review and the authors’ understanding, an examination has never been conducted on MHD double diffusion natural convection of power-law non-Newtonian NEPCMs within a trapezoidal enclosure. The current work is innovative since it combines NEPCMs with the effect of magnetic field Double diffusion Natural Convection of power-law non-Newtonian NEPCMs in a Trapezoidal enclosure. This outcome can be used to improve thermal management in energy storage systems, increasing safety and effectiveness.