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The purpose of this paper is to put forward a nvew reconfigurable multi-mode walking-rolling robot based on the single-loop closed-chain four-bar mechanism, and the robot can be changed to different modes according to the terrain.

Based on the topological analysis, singularity analysis, feasibility analysis, gait analysis and the motion strategy based on motor time-sharing control, the paper theoretically verified that the robot can switch between the four motion modes.

The robot integrates four-bar walking, self-deforming and four-bar and six-bar rolling modes. A series of simulation and prototype experiment results are presented to verify the feasibility of multiple motion modes of the robot.

The work presented in this paper provides a good theoretical basis for further exploration of multiple mode mobile robots. It is an attempt to design the multi-mode mobile robot based on single loop kinematotropic mechanisms. It is also a kind of exploration of the new unknown movement law.

This study aims to develop a four-dimensional (4D) textile composite that self-forms upon thermal stimulation while eliminating thermomechanical programming steps by using fused deposition modeling (FDM) 3D printing technology, and tries to refine the product development path for this composite.

Polylactic acid (PLA) printing filaments were deposited on prestretched Lycra-knitted fabric using desktop-level FDM 3D printing technology to construct a three-layer structure of thermally responsive 4D textiles. Subsequently, the effects of different PLA thicknesses and Lycra knit fabric relative elongation on the permanent shape of thermally responsive 4D textiles were studied. Finally, a simulation program was written, and a case in this study demonstrates the usage of thermally responsive 4D textiles and the simulation program to design a wrist support product.

The constructed three-layer structure of PLA and Lycra knitted fabric can self-form under thermal stimulation. The material can also achieve reversible transformation between a permanent shape and multiple temporary shapes. Thinner PLA deposition and higher relative elongation of the Lycra-knitted fabric result in the greater curvature of the permanent shape of the thermally responsive 4D textile. The simulation program accurately predicted the permanent form of multiple basic shapes.

The proposed method enables 4D textiles to directly self-form upon thermal, which helps to improve the manufacturing efficiency of 4D textiles. The thermal responsiveness of the composite also contributes to building an intelligent human–material–environment interaction system.

This paper aims to investigate the potential for 4D deformation of the smallest building blocks of the material extrusion additive manufacturing (MEAM) process: single extrudates produced with a single material. In contrast to previous 4D printing approaches where property-variations are realised across multiple layers or with complex composites, this study hypothesises that residual strain varies from top-to-bottom within a single printed extrudate and that this offers an opportunity to achieve controllable 4D printing with the smallest possible resolution (single lines in a single layer).

The influences of bed temperature, printing temperature, printing speed, extrusion width, extrusion thickness and activation temperature are quantified in terms of residual strain and 4D curvature.

An almost fourfold variation in curvature was achieved, printing speed and layer thickness greatly affected 4D deformation: the maximum curvature was increased by >600% compared to the minimum curvature when varying printing speed. In addition to rigorous parametric characterisation, a case study demonstrates the 4D deformation of a flat single-layer lattice into a 3D self-formed stent structure comprised of intricate single-extrudate struts. A separate case study demonstrates the resilience of the method by showing results to translate to alternative materials, with alternative printing hardware and with a different 4D activation procedure.

This study successfully proves a new way to achieve intricate 3D structures with the MEAM process, which would be impossible without 4D deformation due to their intricacy and the need for support material. The findings are also relevant to research into undesired warping due to the quantification of residual strain.

The current crisis of sociological theory is due to our failure to do sociology as a positive science‐our failure to accept both explanation and prediction as the goal of theorizing, and to use predictive power as the primary criterion for assessing theories. It is argued that sociology as a positive science can advance sociological theory. It is also argued that a positive science of sociology is possible by correcting four major fallacies‐i.e., fallacies concerning controlled experiments, realism of assumptions, subjectivity, and complexity.

The introduction in Italy in July 2021 of the “COVID-19 Green Certification”, known as the “Green Pass”, was a particularly important moment in the political and social history of the country. While its use for health reasons is debatable both logically and scientifically, its effects should be measured at the general sociological level. The “Green Pass” allowed Italian social life to be shaped according to a social and political profile that can be traced back to a “society of control”. This paper aims to discuss the aforementioned issue.

This paper, of a theoretical nature, intends to verify such an interpretation through a critical survey of Gilles Deleuze's well-known Post-scriptum sur les sociétés de contrôle (1990) and relating the theories to it from cybernetic science, sociology of social systems and the continental philosophy, specifically Michel Foucault. After a short introduction on the history of the instrument's introduction, the paper, divided into parts reflecting the set-up of Deleuze's text, examines the systemic social effects of the “Green Pass” with regard to its logic, and concludes with a reflection on the program of the instrument's future developments.

The “Green Pass” put into practice a model of a society of control as anticipated by Deleuze, verified with particular reference to some instances of Luhmann's theory of social systems, and in the perspective of a Foucault's “normalizing society” in the process of definition and affirmation.

The “Green Pass” has been a controversial tool that has caused forms of social discrimination and exclusion and has seriously questioned the architecture of the rule of law. The conceptual paper tries to reflect on the premises and implications of this instrument.

The approach to the problem both in a critical key and according to concepts and theories of the sociology of social systems, cybernetics and continental philosophy.

This paper aims to present an innovative approach to fabricating an electrically responsive shape memory polymer (SMP).

Polymers that change shape over time when a stimulus is applied are known as SMPs. It uses polylactic acid (PLA) as the base material and carbon nanotubes (CNTs) as conductive additives. Instead of blending CNT with PLA, they were coated on the surface of the samples. The coating consisted of a mixture of CNT/ polycaprolactone. The samples were made using fused deposition modeling, an additive manufacturing method and the shape memory properties of the samples were analyzed under various parameters, including infill angle, coating layers and applied voltage. The voltage generates the Joule heating effect and results in the recovery of SMP to the original shape.

The highest conductivity of samples belongs to three coating layers, whose conductivity is equal to 0.51 S/cm. Under different parameter settings, the highest recorded shape recovery ratio reached 71.47% at voltage 60, infill angle 0 / 90 and two coating layers. This value emphasizes the remarkable ability of the developed material to return to its original shape. Furthermore, the maximum shape recovery speed observed was 0.3593 degree/s, providing valuable information about shape recovery speed under optimal conditions.

This paper presents the surface coating method and the effects of process parameters for activating shape memory using electric current. Compared to previous techniques, this method offers higher speed and requires less material, making it suitable for use in various industries.

The purpose of this paper is the theoretical presentation of tensorial formulation with surface mobility forces and numerical verification of Reynolds thermal transpiration law in a contemporary experiment with nanoflow.

The velocity profiles in a single microchannel are calculated by solving the momentum equations and using thermal transpiration force as the boundary conditions. The mass flow rate and pressure of unstationary thermal transpiration modeling of the benchmark experiment has been achieved by the implementation of the thermal transpiration mobility force closure for the thermal momentum accommodation coefficient.

An original and easy-to-implement method has been developed to numerically prove that at the final equilibrium, i.e. zero-flow state, there is a connection between the Poiseuille flow in the center of channel and counter thermal transpiration flow on the surface. The numerical implementation of the Reynolds model of thermal transpiration has been performed, and its usefulness for the description of the benchmark experiment has been verified.

The simplified procedure requires the measurement or assumption of the helium-glass slip length.

The procedure can be very useful in the design of micro-electro-mechanical systems and nano-electro-mechanical systems, especially for accommodation pumping.

The paper discussed possible constitutive equations in the transpiration shell-like layer. The new approach can be helpful for modeling phenomena occurring at a fluid–solid phase interface at the micro- and nanoscales.