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The purpose of this paper is to present a programming by demonstration (PbD) system based on 3D stereoscopic vision and inertial sensing that provides a cost-effective pose tracking system, even during error-prone situations, such as camera occlusions.

The proposed PbD system is based on the 6D Mimic innovative solution, whose six degrees of freedom marker hardware had to be revised and restructured to accommodate an IMU sensor. Additionally, a new software pipeline was designed to include this new sensing device, seeking the improvement of the overall system’s robustness in stereoscopic vision occlusion situations.

The IMU component and the new software pipeline allow the 6D Mimic system to successfully maintain the pose tracking when the main tracking tool, i.e. the stereoscopic vision, fails. Therefore, the system improves in terms of reliability, robustness, and accuracy which were verified by real experiments.

Based on this proposal, the 6D Mimic system reaches a reliable and low-cost PbD methodology. Therefore, the robot can accurately replicate, on an industrial scale, the artisan level performance of highly skilled shop-floor operators.

To the best of the authors’ knowledge, the sensor fusion between stereoscopic images and IMU applied to robot PbD is a novel approach. The system is entirely designed aiming to reduce costs and taking advantage of an offline processing step for data analysis, filtering and fusion, enhancing the reliability of the PbD system.

Since proposed by Darwin, evolution is considered to be dependent on a source of genetic variability that must be constrained by environmental conditions in order to generate stable (adapted) phenotypes. Several sources and causes of this variability have been proposed so far. This paper aims to posit that ambiguity of fuzzy grammars is the main source of genetic variability on which natural selection operates.

Formal grammars (FG) were proposed as the tool to deal with human and artificial languages. Fuzzy formal grammars (FFGs) are the extension of the formalism in the Theory of Fuzzy Logic and are ambiguous grammars. Here, the ambiguity of the ordered set of chemical interactions – the so‐called signal transduction pathways (stp), linking membranes events to DNA reading and protein synthesis – is assumed as an inner source of variability that must be constrained by environmental conditions. Fuzzy formal languages (FFL) theory is used to mathematically formalize the biology concept of stp.

The genome variability is the result of the constraints imposed by the environment on the grammar intrinsic ambiguity.

The formalism of this model provides a new way to analyze and interpret the findings of the different genome sequencing projects.

The theoretical framework developed here provides a new perspective of understanding the code of life and evolution.

This second part of a companion paper seeks to extend the theory proposed to apply the hierarchy of fuzzy formal language to cope with the three major phenomenon of life: replication, control and shuffling of genetic information.

In order to cope with the proposal, three new classes of FFG are proposed: replicating grammars: to formalize properties and consequences of DNA duplication; self‐controlled grammars: to provide the tools to control the grammar ambiguity and to improve adaptability, and recombinant grammars: to formalize properties and consequences of the sexual reproduction to life evolution. Considering all these facts, FFG are proposed as the key instrument to formalize the basic properties of the chemical transactions supporting life.

The formalism of the model provides a new way to analyze and interpret the findings of the different genome sequencing projects.

The theoretical framework developed here provides a new perspective of understanding the code of life and evolution.

Social movement research often focusses on phases of success and large protest events. By contrast, taking an interest in the question of how organizational change occurs within social movements, this study points out the importance of phases of low protest activity. The organizational structure of the Portuguese anti-austerity protests provides a thought-provoking case, as large protests organized by civil society actors other than the trade unions were a novelty in 2011. Furthermore, there are long periods of absence of large protests, and the organizational structure of the protests has undergone significant changes. Based on fieldwork in Portugal between September 2011 and March 2013, I differentiate between four phases in the organization of protests against austerity. I argue that it is mainly times of low degrees of activism – times that are rarely taken into account by social movement research – that lead to radical changes in the organizational structure of a social movement. The impact of the following factors on the direction of change is analyzed: (a) strategic choice; (b) values and normative commitments; (c) (potential) alliances and participants; (d) inspiration from other cases of social movement activism; and (e) learning processes, the history of social movements and the impact of memory.

This study aims to evaluate two bacterial cellulose (BC) films as an alternative textile surface suitable for use in the manufacture of clothing prototypes.

A combination of experiments for the production and characterization of BC films with traditional techniques for sewing fabrics was carried out. BC films were produced from the bacterum Gluconacetobacter hansenii UCP1619 and from Kombucha, a consortium of microorganisms grown on sugared tea. The BC films were then purified, characterized by scanning electron microscopy (SEM) and evaluated for mechanical strength. Two clothing prototypes were developed by combining BC films with a flat fabric composed of 70% linen and 30% polyester to assess the viability of the garment for future clothing making using biomaterials.

The results showed that the combination of flat fabric with BC-based biomaterials is a viable alternative for the innovative use of BC films in the manufacture of apparel products, especially after optimizing the mechanical properties of the artefact.

BC application studies in the textile industry are still in their early stages, although they are attracting more and more the attention of researchers around the world. The experiments carried out in this research provide new information on the handling and application of this material in innovative products for the textile industry.

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.

Two kinds of time integration methods; the dynamic explicit method and the static implicit method, have been compared, especially with emphasis on the shell formulations and the stress integration methods. Two methods have been applied to the benchmark problem named the S‐rail stamping process, provided by NUMISHEET’96 committee, in order to compare their numerical results with each other and with the average values of the experiments as well. Based on the comparisons, it is shown that both time integration methods can be successfully applied to industrial sheet metal stamping simulations. In detail, the static implicit method is advantageous over the dynamic explicit method in terms of accuracy, while the latter is known to be more efficient than the former in terms of computation efficiency.