Selective Assembly Research Articles

A novel method of optimized selective assembly for remanufactured products

A novel method of optimized selective assembly for remanufactured products

Foldaxane-Based Switchable [c2]Daisy Chains.

Artificial molecular muscles are highly attractive in the field of molecular machinery due to their unique properties of contraction and stretching motion. However, the synthesis of molecular muscles poses formidable challenges as it is hindered by undesirable yields and poor selectivity. Herein, we present a procedure for the dynamic assembly of foldaxane-based [c2]daisy chains, wherein the hermaphroditic sequences consisting of aromatic helices and peptide rods are interlocked through inter-strand hydrogen-bonding interactions. The binding complementarity facilitates a selective and efficient assembly of [c2]daisy chain structures, inhibiting the creation of by-products. Introducing multiple recognition sites confers the system with contraction and stretching motion actuated by chemical stimuli. The rate of this muscle-like motion is calculated to be 0.8 s-1, which is 107 times faster than that of complex dissociation.

Foldaxane‐Based Switchable [c2]Daisy Chains

AbstractArtificial molecular muscles are highly attractive in the field of molecular machinery due to their unique properties of contraction and stretching motion. However, the synthesis of molecular muscles poses formidable challenges as it is hindered by undesirable yields and poor selectivity. Herein, we present a procedure for the dynamic assembly of foldaxane‐based [c2]daisy chains, wherein the hermaphroditic sequences consisting of aromatic helices and peptide rods are interlocked through inter‐strand hydrogen‐bonding interactions. The binding complementarity facilitates a selective and efficient assembly of [c2]daisy chain structures, inhibiting the creation of by‐products. Introducing multiple recognition sites confers the system with contraction and stretching motion actuated by chemical stimuli. The rate of this muscle‐like motion is calculated to be 0.8 s−1, which is 107 times faster than that of complex dissociation.

Complete Kinematics/Dynamics Modeling and Performance Analysis of a Novel SCARA Parallel Manipulator Based on Screw Theory

Abstract In this paper, a novel Selective Compliance Assembly Robot Arm (SCARA) high-speed parallel manipulator that can realize three-translation and one-rotation motion is proposed, and an accurate dynamic modeling methodology is investigated. The mechanism is composed of four limbs with a double parallelogram structure and a single moving platform. The high bearing capacity and high dynamic response of the novel mechanism make it a viable alternative choice for this kind of automation equipment. The degree-of-freedom (DOF) of the mechanism is analyzed by the screw theory. At the same time, the velocity mapping model of the mechanism is established by the twist screw and the actuated Jacobian matrix. Then, the acceleration mapping model of the mechanism, including the generalized kinematic pairs, is established by reduced acceleration state, the modified Lie screw, and the acceleration Hessian matrix. On this basis, the complete dynamic model with a compact form of the mechanism is deduced by the combination of screw theory and virtual work principle, and the correctness of the developed model is verified by multibody simulation software. Finally, considering the inertial characteristics of the mechanism, the dynamic performance distribution in the reachable workspace of the mechanism is analyzed by the Joint-Reflected Inertia (JRI) index and Coefficient of Variation of joint-space Inertia (CVI) index, and some areas are selected as the task workspace using the above index to guarantee good dynamic performance.

A second-order tolerance analysis approach to statistical virtual assembly for rigid parts

Virtual assembly has become a popular trend in recent years and is used for various purposes, including selective assembly and adaptive tooling. Monte Carlo approaches based on Finite Element Method (FEM) simulations are commonly used for production applications. However, during the design phase, when testing different configurations and design options, a variational method is more suitable. This paper aims to test different implementations of the Method of System Moments applied to the second-order tolerance analysis method when actual distributions, which are non-centered and non-normal, are used as input for the simulation. The study reveals that the simulation results can significantly vary depending on the simulation settings in some cases. As a result, a series of best practices are highlighted to improve the accuracy and reliability of the simulation outcomes.

Revisiting the chaperonin T-complex protein-1 ring complex in human health and disease: A proteostasis modulator and beyond.

Disrupted protein homeostasis (proteostasis) has been demonstrated to facilitate the progression of various diseases. The cytosolic T-complex protein-1 ring complex (TRiC/CCT) was discovered to be a critical player in orchestrating proteostasis by folding eukaryotic proteins, guiding intracellular localisation and suppressing protein aggregation. Intensive investigations of TRiC/CCT in different fields have improved the understanding of its role and molecular mechanism in multiple physiological and pathological processes. In this review, we embark on a journey through the dynamic protein folding cycle of TRiC/CCT, unraveling the intricate mechanisms of its substrate selection, recognition, and intriguing folding and assembly processes. In addition to discussing the critical role of TRiC/CCT in maintaining proteostasis, we detail its involvement in cell cycle regulation, apoptosis, autophagy, metabolic control, adaptive immunity and signal transduction processes. Furthermore, we meticulously catalogue a compendium of TRiC-associated diseases, such as neuropathies, cardiovascular diseases and various malignancies. Specifically, we report the roles and molecular mechanisms of TRiC/CCT in regulating cancer formation and progression. Finally, we discuss unresolved issues in TRiC/CCT research, highlighting the efforts required for translation to clinical applications, such as diagnosis and treatment. This review aims to provide a comprehensive view of TRiC/CCT for researchers to inspire further investigations and explorations of potential translational possibilities.

Design and development of dual-extruder food 3D printer based on selective compliance assembly robot arm and printing of various inks

Recent research in food 3D printing mainly focuses on ink materials, with relatively limited research on printer equipment development. Furthermore, the development of traditional food three-axis 3D printer is high cost and low productivity. In this study, we developed a dual extruder for food 3D printing, and designed a dual-extruder system based on Selective Compliance Assembly Robot Arm (SCARA) equipment. The productivity was determined by measuring significance analysis on the physical dimensions and the texture characteristics of the printed products using single/dual-extruder. A variety of food inks were experimented and various self-developed print paths were experimented with. The results of the two sets of significance analyses on physical dimensions and texture characteristics lead to the conclusion that the development of the dual-extruder system based on the SCARA machine arm successfully improved productivity. This also verified the broad adaptability of the device's inks, which operate on the principle of air pressure extrusion. We believe that this finding provides a new research direction for 3D printing of food products.

Assembly and Utility of a Drawstring-Mimetic Supramolecular Complex.

Inspired by the drawstring structure in daily life, here we report the development of a drawstring-mimetic supramolecular complex at the molecular scale. This complex consists of a rigid figure-of-eight macrocyclic host molecule and a flexible linear guest molecule which could interact through three-point non-covalent binding to form a highly selective and efficient host-guest assembly. The complex not only resembles the drawstring structure, but also mimics the properties of a drawstring with regard to deformations under external forces. The supramolecular drawstring can be utilized as an interlocked crosslinker for poly(methyl acrylate), and the corresponding polymer samples exhibit comprehensive enhancement of macroscopic mechanical performance including stiffness, strength, and toughness.

Precise and selective macroscopic assembly of a dual lock-and-key structured hydrogel.

Macroscopic assembly offers immense potential for constructing complex systems due to the high design flexibility of the building blocks. In such assembly systems, hydrogels are promising candidates for building blocks due to their versatile chemical compositions and ease of property tuning. However, two major challenges must be addressed to facilitate application in a broader context: the precision of assembly and the quantity of orthogonally matching pairs must both be increased. Although previous studies have attempted to address these challenges, none have successfully dealt with both simultaneously. Here, we propose topology-based design criteria for the selective assembly of hydrogel building blocks. By introducing the dual lock-and-key structures, we demonstrate highly precise assembly exclusively between the matching pairs. We establish principles for selecting multiple orthogonally matching pairs and achieve selective assembly involving simple one-to-one matching and complex assemblies with multiple orthogonal matching points. Moreover, by harnessing hydrogel tunability and the abundance of matching pairs, we synthesize complementary single-stranded structures for programmable assembly and successfully assemble them in the correct order. Finally, we demonstrate a hydrogel-based self-assembled logic gate system, including a YES gate, an OR gate, and an AND gate. The output is generated only when the corresponding inputs are provided according to each logic.

Selective assembly and insertion of ubiquicidin antimicrobial peptide in lipid monolayers.

Antimicrobial-resistant bacteria pose a significant threat to humans, prompting extensive research into developing new antimicrobial peptides (AMPs). The biomembrane is the first barrier of a biological cell, hence, comprehending the interaction and self-assembly of AMPs in and around such membranes is of great importance. In the present study, several biophysical techniques have been applied to explore the self-assembly of ubiquicidin (29-41), an archetypical AMP, in and around the phospholipid monolayers formed at air-water interface. Such a monolayer mimics one of the leaflets of a lipid bilayer. The surface pressure-area isotherm exhibits the strongest interaction with a negatively charged lipid, 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) (DPPG). The weakest affinity was towards the zwitterionic lipid, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Another zwitterionic lipid, 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE), shows an intermediate affinity. This affinity was quantified by analyzing alterations in the effective mean molecular area of the lipid, the in-plane compressional modulus of the assembly, and the electrostatic potential induced by the presence of peptides. The precise organization of the peptide around the lipid monolayer at a sub-nanometre length scale was revealed using synchrotron-based X-ray reflectivity measurements from the air-water interface. Information about the selective interaction of the peptide with lipids and their varied orientation at the lipid-water interface could be useful in understanding the selectivity of AMP in developing new antibiotics.

Topological control in paddlewheel metal-organic cages via ligand length variation.

Varying the length of phenanthrene-derived ligands switches the selective assembly of MIInLn metal-organic cages (MOCs, n = 6 or 8) between tetrahedral, square, or triangular architectures. The limit of this approach is explored for both Cu2 and Rh2 paddlewheel MOCs, and supported by solution, solid-state and computational analysis.

Direct Imaging of "Patch-Clasping" and Relaxation in Robust and Flexible Nanoparticle Assemblies.

Polymer patching on inorganic nanoparticles (NPs) enables multifunctionality and directed self-assembly into nonclosely packed optical and mechanical metamaterials. However, experimental demonstration of such assemblies has been scant due to challenges in leveraging patch-induced NP-NP attractions and understanding NP self-assembly dynamics. Here we use low-dose liquid-phase transmission electron microscopy to visualize the dynamic behaviors of tip-patched triangular nanoprisms upon patch-clasping, where polymer patches interpenetrate to form cohesive bonds that connect NPs. Notably, these bonds are longitudinally robust but rotationally flexible. Patch-clasping is found to allow highly selective tip-tip assembly, interconversion between dimeric bowtie and sawtooth configurations, and collective structural relaxation of NP networks. The integration of single particle tracking, polymer physics theory, and molecular dynamics simulation reveals the macromolecular origin of patch-clasping-induced NP dynamics. Our experiment-computation integration can aid the design of stimuli-responsive nanomaterials, such as topological metamaterials for chiral sensors, waveguides, and nanoantennas.

Desain Sistem Mekanik Robot SCARA untuk Internet Nuclear Instrumentation Laboratory

Radiation protection training requires a robotic arm as a radiation shield regulator that can be controlled remotely to reduce radiation risk. The required robot is a Selective Compliance Assembly Robot Arm (SCARA) type robotic arm. This research aims to design a mechanical system for the SCARA robot for the Internet Nuclear Instrumentation Laboratory (INIL). The research method for making robots begins with a 3D CAD design followed by manufacturing and assembly. Robot control using the Arduino IDE application. Robotic arm testing using stress analysis from Autodesk Inventor software and movement and accuracy testing. The results of the research have successfully designed robotic arms with dimensions of 50.8 cm high, 14 cm wide, and 56 cm long. The robot's work area is 189 cm2, with the farthest range being 30 cm. Keywords: radiation protection, mechanical design, SCARA robot, robotic arm, NPP, INIL

SCARA TIPI 3D YAZICI TASARIMI VE İMALİ

This study designed and produced a Selective Compliance Assembly Robot Arm (SCARA)-type three-dimensional Fused Deposition Modelling (FDM) printer with three degrees of freedom based on kinematic and dynamic analyses. The dynamic capability of a SCARA robot and the FDM production method were combined, and a unique printer system was obtained by using open-source software. The Kinematic Calculations were achieved by analytical methods by using geometrical equations. An open-loop control system was created by inputting forward kinematic and inverse kinematic equations to the control software. The printing processes of the Cube and Prism samples were carried out with the SCARA-type three-dimensional printer. The data obtained from the analytical calculations and the results obtained from the experiments were compared, and the error rates in the desired and obtained prints and findings that were obtained based on print quality were shared. Academic studies on SCARA in the literature have usually focused on the dynamic calculations, design and control of SCARA robots, and especially in recent years, implementation of nature-inspired algorithms. A unique printer system was obtained by using open-source software. Prints were taken from cube and prism samples, and the samples were compared to the data obtained from the analytical results.This study implemented a form of a hybrid printer model where the movement capability of a SCARA robot was combined with FDM-type three-dimensional printer production technology. The SCARA-type three-dimensional printer was produced after making kinematic and kinetic calculations.

Ligand-modulated nickel-catalyzed regioselective silylalkylation of alkenes

Organosilicon compounds have shown tremendous potential in drug discovery and their synthesis stimulates wide interest. Multicomponent cross-coupling of alkenes with silicon reagents is used to yield complex silicon-containing compounds from readily accessible feedstock chemicals but the reaction with simple alkenes remains challenging. Here, we report a regioselective silylalkylation of simple alkenes, which is enabled by using a stable Ni(II) salt and an inexpensive trans−1,2-diaminocyclohexane ligand as a catalyst. Remarkably, this reaction can tolerate a broad range of olefins bearing various functional groups, including alcohol, ester, amides and ethers, thus it allows for the efficient and selective assembly of a diverse range of bifunctional organosilicon building blocks from terminal alkenes, alkyl halides and the Suginome reagent. Moreover, an expedient synthetic route toward alpha-Lipoic acid has been developed by this methodology.

On-Demand Assembly of Nanocrystals into a Superstructure Library in Co(OH)2 Single-Walled Nanotubes.

The hierarchical self-assembly of colloidal particles facilitates the bottom-up manufacturing of metamaterials with synergistically integrated functionalities. Here, we define a modular assembly methodology that enables multinary co-assembly of nanoparticles in one-dimensional confined space. A series of isotropic and anisotropic nanocrystals such as plasmonic, metallic, visible, and near-infrared responsive nanoparticles as well as transition-metal phosphides can be selectively assembled within the single-walled Co(OH)2 nanotubes to achieve various increasingly sophisticated assembly systems, including unary, binary, ternary, and quaternary superstructures. Moreover, the selective assembly of distinct functional nanoparticles produces different integrated functional superstructures. This generalizable methodology provides predictable pathways to complex architectures with structural programming and customization that are otherwise inaccessible.

The impact of primary colonizers on the community composition of river biofilm.

As a strategy for minimizing microbial infections in fish hatcheries, we have investigated how putatively probiotic bacterial populations influence biofilm formation. All surfaces that are exposed to the aquatic milieu develop a microbial community through the selective assembly of microbial populations into a surface-adhering biofilm. In the investigations reported herein, we describe laboratory experiments designed to determine how initial colonization of a surface by nonpathogenic isolates from sturgeon eggs influence the subsequent assembly of populations from a pelagic river community, into the existing biofilm. All eight of the tested strains altered the assembly of river biofilm in a strain-specific manner. Previously formed isolate biofilm was challenged with natural river populations and after 24 hours, two strains and two-isolate combinations proved highly resistant to invasion, comprising at least 80% of the biofilm community, four isolates were intermediate in resistance, accounting for at least 45% of the biofilm community and two isolates were reduced to 4% of the biofilm community. Founding biofilms of Serratia sp, and combinations of Brevundimonas sp.-Hydrogenophaga sp. and Brevundimonas sp.-Acidovorax sp. specifically blocked populations of Aeromonas and Flavobacterium, potential fish pathogens, from colonizing the biofilm. In addition, all isolate biofilms were effective at blocking invading populations of Arcobacter. Several strains, notably Deinococcus sp., recruited specific low-abundance river populations into the top 25 most abundant populations within biofilm. The experiments suggest that relatively simple measures can be used to control the assembly of biofilm on the eggs surface and perhaps offer protection from pathogens. In addition, the methodology provides a relatively rapid way to detect potentially strong ecological interactions between bacterial populations in the formation of biofilms.

Visible and selective gel assembly via covalent click chemistry

AbstractThis study marks the birth of visible and selective click covalent assembly. It is achieved by amplifying orthogonal alkyne−azide click chemistry through interfacial multisite interactions between azide/alkyne functionalized polymer hydrogels. Macroscopic assembly of hydrogels via host−guest chemistry or noncovalent interactions such as electrostatic interactions has been reported. Unlike macroscopic supramolecular assembly, here we report visible and selective “click” covalent assembly of hydrogels at the macroscale. LEGO‐like hydrogels modified with alkyne and azide groups, respectively, can click together via the formation of covalent bonds. Monomer concentration‐dependent assembly and selective covalent assembly have been studied. Notably, macroscopic gel assembly clearly elucidates click preferences and component selectivity not observed in the solution reactions of competing monomers.

Collision Avoidance for a Selective Compliance Assembly Robot Arm Manipulator Using Topological Path Planning

Industrial applications with robotic manipulators have grown and made production systems increasingly efficient. However, there are still some limitations that can delay production, causing losses. Several factors, such as accidents and collisions of manipulator robots with operators and other machines, can cause unforeseen stops. Thus, this work aims to develop a trajectory planning method to avoid collisions applied to a selective compliance assembly robot arm (SCARA) robotic manipulator in the context of collaborative robotics. The main contribution of this paper is a path planning method based on mathematical morphology, named topological path planning (TPP). Through some evaluation metrics such as the number of path points, computing time, distance, standard deviation of the joint acceleration, and maximum acceleration rate along the path, we show that TPP is a collision-free, deterministic, and predictable route planning. In our experiments, our proposal presented better results for applications in industrial robotic manipulators when compared to the probabilistic roadmap method (PRM) and TPP*, a particular case of TPP that is similar to the generalized Voronoi diagram (GVD).

Patterning-Based Self-Assembly of Specific and Functional Structures

In this study, we developed a system for selective self-assembly of millimeter-scale components differentiated by adhesive patterns. This was achieved by designing concentric circular patterns having different radii but the same total length of peripheries. Small polymer sheets having solder adhesive patterns in these designs were simply attached to the millimeter-scale components to be assembled in a stirring container. This strategy was effective in avoiding an overlap between different patterns and enforcing the selective bonds between identical patterns among three types of components. Finally, the selective assembly of a functional structure (i.e., poly(N-isopropylacrylamide) gel actuator) was demonstrated.