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The purpose of this paper is to develop and test control methods for real‐time automatic presser‐foot force control in industrial sewing machines. In this work, a closed‐loop controller that controls presser‐foot maximum vertical displacement is presented and compared to existing solutions that adjust force depending on sewing speed. Automatic force control can reduce problems such as stitch irregularity, stitch distortions and material damage, besides making material handling easier.

An electromagnetic force actuator was integrated in an industrial lockstitch machine. A computer‐based control system was designed implementing either speed‐variable force control, closed‐loop control, or emulating a traditional constant‐force system. Maximum presser‐foot displacement values were measured and analysed in relevant sewing situations, and seam quality was assessed.

Constant‐force control does not allow optimal force setting at all speeds. Speed‐variable force control is an improvement, but requires empirical setting of the speed‐force relation, not always assuring optimal operation. Closed‐loop control adapts force to the requirement of each sewing situation more precisely. Sewing quality is good and material handling is eased.

The actuator has to be optimised regarding response time and maximum force. Some aspects in the behaviour of the control system and actuator have to be further studied.

The proposed control system enables the automatic setting and adaptation of force to all sewing situations, making material handling easier at low speeds without compromising feeding performance at high speed. The closed‐loop controller may be used as a teach‐in system for speed‐dependent control.

This is the first prototype of a closed‐loop control system for presser‐foot force on a lockstitch sewing machine and the first comparative study of control methods for presser‐foot force control.

The motivation for robotics research in the agricultural field has sparked in consequence of the increasing world population and decreasing agricultural labor availability. This paper aims to analyze the state of the art of pruning and harvesting manipulators used in agriculture.

A research was performed on papers that corresponded to specific keywords. Ten papers were selected based on a set of attributes that made them adequate for review.

The pruning manipulators were used in two different scenarios: grapevines and apple trees. These manipulators showed that a light-controlled environment could reduce visual errors and that prismatic joints on the manipulator are advantageous to obtain a higher reach. The harvesting manipulators were used for three types of fruits: strawberries, tomatoes and apples. These manipulators revealed that different kinematic configurations are required for different kinds of end-effectors, as some of these tools only require movement in the horizontal axis and others are required to reach the target with a broad range of orientations.

This work serves to reduce the gap in the literature regarding agricultural manipulators and will support new developments of novel solutions related to agricultural robotic grasping and manipulation.

The purpose of this paper is to construct a numerical model for the numerical analysis of the hydraulic transient profile in Trabalhador channel for filling and emptying maneuvers and to determine the water level in time. Model results support operational managers in the decision-making process.

Physical data were provided for the construction and calibration of the numerical model. The equations of Saint-Venant were approximated by a finite difference scheme and the numerical model was written in Fortran. The results of filling and emptying of the channel simulations were compared with the measured water levels.

Measured water levels and those simulated by the numerical model have shown good correlation. The time recorded for the filling and emptying of the canal was also close between the measured and simulated data. The simulation design flow pointed to inundation in the channel banks. Simulation water levels were slightly higher than those measured.

In this model, the combination of canals and pressure conduits was not considered.

The findings confirm the measured time for filling and emptying of the canal, as well as inundation of canal banks for the maximum design flow. These results help in the management process.

This paper presents a numerical model for hydraulic transient analysis in channels with good agreement with the field data.

This paper aims to propose a translation library capable of generating robots proprietary code after their offline programming has been performed in a software application, named AdaptPack Studio, running over a robot simulation and offline programming software package.

The translation library, named AdaptPack Studio Translator, is capable to generate proprietary code for the Asea Brown Boveri, FANUC, Keller und Knappich Augsburg and Yaskawa Motoman robot brands, after their offline programming has been performed in the AdaptPack Studio application.

Simulation and real tests were performed showing an improvement in the creation, operation, modularity and flexibility of new robotic palletizing systems. In particular, it was verified that the time needed to perform these tasks significantly decreased.

The design and setup of robotics palletizing systems are facilitated by an intuitive offline programming system and by a simple export command to the real robot, independent of its brand. In this way, industrial solutions can be developed faster, in this way, making companies more competitive.

The effort to build a robotic palletizing system is reduced by an intuitive offline programming system (AdaptPack Studio) and the capability to export command to the real robot using the AdaptPack Studio Translator. As a result, companies have an increase in competitiveness with a fast design framework. Furthermore, and to the best of the author’s knowledge, there is also no scientific publication formalizing and describing how to build the translators for industrial robot simulation and offline programming software packages, being this a pioneer publication in this area.

This paper aims to propose an automated framework for agile development and simulation of robotic palletizing cells. An automatic offline programming tool, for a variety of robot brands, is also introduced.

This framework, named AdaptPack Studio, offers a custom-built library to assemble virtual models of palletizing cells, quick connect these models by drag and drop, and perform offline programming of robots and factory equipment in short steps.

Simulation and real tests performed showed an improvement in the design, development and operation of robotic palletizing systems. The AdaptPack Studio software was tested and evaluated in a pure simulation case and in a real-world scenario. Results have shown to be concise and accurate, with minor model displacement inaccuracies because of differences between the virtual and real models.

An intuitive drag and drop layout modeling accelerates the design and setup of robotic palletizing cells and automatic offline generation of robot programs. Furthermore, A* based algorithms generate collision-free trajectories, discretized both in the robot joints space and in the Cartesian space. As a consequence, industrial solutions are available for production in record time, increasing the competitiveness of companies using this tool.

The AdaptPack Studio framework includes, on a single package, the possibility to program, simulate and generate the robot code for four different brands of robots. Furthermore, the application is tailored for palletizing applications and specifically includes the components (Building Blocks) of a particular company, which allows a very fast development of new solutions. Furthermore, with the inclusion of the Trajectory Planner, it is possible to automatically develop robot trajectories without collisions.

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

The objective of this study is to propose a sequence of implementation of the core characteristics of reconfigurability: modularity, integrability, diagnosability, adaptability and customization. For this purpose, the relationships among the core characteristics and Industry 4.0 technologies are analyzed as well as the impacts of one core characteristic on another.

This study presented tests and validated two hypothesized models based on the literature. This paper was based on a questionnaire survey. Portuguese manufacturing companies were the sampling frame. In total, 600 questionnaires were distributed and a total of 112 responses were eligible for statistical processing, representing a response rate of 18.7%. Structural equation modeling (SEM) was used to hypothesize the sequence of implementation of the core characteristics of reconfigurability.

The findings presented a roadmap to implement reconfigurability, which implies significant managerial contributions on how to make the transition from conventional to reconfigurable manufacturing systems (RMSs). This highlights the importance of the sequence of implementation of the core characteristics in order to make the most of each to achieve reconfigurability.

Implementing reconfigurability is crucial to manufacturing companies to respond to changes in production requirements and market fluctuations quickly. However, there is a gap between theory and practice in regard to achieve reconfigurability in existing manufacturing systems. This gap includes (1) understanding the type of relationships among the core characteristics of reconfigurability, (2) understanding the influence that one core characteristic has on another and (3) establishing a sequence of implementation for the core characteristics. This study makes a contribution to fill this gap in the research area.

The livestock sector contributes significantly to the Brazilian economy, but also creates many environmental and social issues. To mitigate these problems and help counteract the effects of the growing production demand, it is essential to address the prevention of food loss and waste (FLW). Therefore, the aim of the present study is to identify the causes of FLW, model their interrelationships and determine their root causes for the Brazilian beef supply chain (SC).

16 causes are analysed using an integrated interpretive structural modelling (ISM) and matrix impact of cross-multiplication applied to classification (MICMAC) methodology. ISM identified interrelationships among the causes and MICMAC determined the root causes of FLW.

The ISM highlights the “Lack of transportation infrastructures”, “Inadequate handling”, “Poor operational performance”, “Variety of products available in supermarkets” and “Unhealthy animals and outbreaks of disease” as the most influential causes and the MICMAC classifies them as the root causes of FLW in the Brazilian beef SC.

The results provide fundamental insights for researchers, practitioners and policymakers, by exploring which causes are more influential and which are the root causes, thereby assisting the SC members in the definition of suitable strategies to mitigate FLW.

This is the first empirical analysis of the interdependencies between the causes of FLW in the beef SC.

The purpose of this paper is to investigate the current level of reconfigurability implementation and its impact on manufacturing systems’ operational performance empirically.

This study is based on a questionnaire survey. Statistical analysis procedures were adopted to accomplish its objectives, namely, clustering methods based on cluster centroids. An ANOVA analysis was used to test for cluster differences among the variables.

The results show that the manufacturing companies surveyed can be divided into three clusters, with different levels of reconfigurability implemented. The implementation of the core characteristics of reconfigurability depends on the product’s complexity and demand variability, in terms of volume and product mix, as these have an impact on the operational performance, in terms of quality, delivery and flexibility.

The data for this survey were collected from manufacturing companies based in Portugal. Therefore, the replication of this questionnaire in other countries is recommended for future research to confirm its findings.

The questionnaire developed could be used by managers to assess the level of reconfigurability of their production systems and for internal/external benchmarking. The findings may help managers to decide which core characteristics should be implemented in their manufacturing systems.

The majority of the research addressing performance issues in reconfigurable manufacturing systems has been applied to case studies. This research reports an empirical investigation using a questionnaire-based methodology to provide generalisable empirical evidence.