Shape memory polymer adhesive gripper for pick-and-place applications

Over the past few years, shape memory polymers (SMPs) have been extensively studied in term of their remarkable reversible dry adhesive properties and related smart adhesive applications. However, these exceptional properties of SMPs have not been exploited for pick-and-place applications, which would otherwise advance the robotic manipulation. This work explores the use of SMPs to design an adhesive gripper which pick and place target solid objects relying on reversible dry adhesion of SMP. Compared with common finger or soft grippers, the SMP adhesive gripper interacts with a single surface of a target object for pick-and-place. Furthermore, it is easy and inexpensive to manufacture and applicable to various surfaces since it involves reversible dry adhesion. In this paper, associated physical mechanisms and temperature analyses are studied and conducted. Also, the study includes manufacturing of a dual SMP and a release tip which substantially enhances the adhesion strength and considerably minimizes the releasing force. Finally, the versatility and utility of the SMP adhesive gripper are demonstrated through pick-and-place experiments

Orbital-selective Mott and Peierls transition in HxVO2

Materials displaying metal-insulator transitions (MITs) as a function of external parameters such as temperature, pressure, or composition are most intriguing from the fundamental point of view and also hold high promise for applications. Vanadium dioxide (VO2) is one of the most prominent examples of MIT having prospective applications ranging from intelligent coatings, infrared sensing, or imaging, to Mott memory and neuromorphic devices. The key aspects conditioning possible applications are the controllability and reversibility of the transition. Here we present an intriguing MIT in hydrogenated vanadium dioxide, HxVO2. The transition relies on an increase of the electron occupancy through hydrogenation on the transition metal vanadium, driving the system insulating by a hybrid of two distinct MIT mechanisms. The insulating phase observed in HVO2 with a nominal d2 electronic configuration contrasts with other rutile d2 systems, most of which are metallic. Using spectroscopic tools and state-of-the-art many-body electronic structure calculations, our investigation reveals a correlation-enhanced Peierls and a Mott transition taking place in an orbital-selective manner cooperate to stabilize an insulating phase. The identification of the hybrid mechanism for MIT controlled by hydrogenation opens the way to radically design strategies for future correlated oxide devices by controlling phase reversibly while maintaining high crystallinity

Tuning orbital-selective phase transitions in a two-dimensional Hund's correlated system

Hund's rule coupling ($\textit{J}$) has attracted much attention recently for its role in the description of the novel quantum phases of multi orbital materials. Depending on the orbital occupancy, $\textit{J}$ can lead to various intriguing phases. However, experimental confirmation of the orbital occupancy dependency has been difficult as controlling the orbital degrees of freedom normally accompanies chemical inhomogeneities. Here, we demonstrate a method to investigate the role of orbital occupancy in $\textit{J}$ related phenomena without inducing inhomogeneities. By growing SrRuO$_3$ monolayers on various substrates with symmetry-preserving interlayers, we gradually tune the crystal field splitting and thus the orbital degeneracy of the Ru \textit{t_2_g$}$ orbitals. It effectively varies the orbital occupancies of two-dimensional (2D) ruthenates. Via in-situ angle-resolved photoemission spectroscopy, we observe a progressive metal-insulator transition (MIT). It is found that the MIT occurs with orbital differentiation: concurrent opening of a band insulating gap in the $\textit{d$_x_y} band and a Mott gap in the \textit{d_x$$_z$$_/$$_y$$_z} bands. Our study provides an effective experimental method for investigation of orbital-selective phenomena in multi-orbital materials

Development and evaluation of open-source IEEE 1547.1 test scripts for improved solar integration

Distributed Energy Resources (DERs) equipped with standardized, interoperable, grid-support functionality have the capability to provide a range of services for power system operators. These requirements have been recently codified in the 2018 revision of the American DER interconnection and interoperability standard, IEEE Std. 1547, as well as the revised Canadian interconnection standard, CSA C22.3 No. 9. Currently, the IEEE standards committee is drafting a new revision of the IEEE Std. 1547.1 test standard, which outlines the test procedures for certifying equipment compliant to IEEE Std. 1547. In addition, it is often referenced as a test standard in CSA C22.3 No. 9. This draft test standard has not been fully exercised yet to identify mistakes, redundancies, and/or implementation challenges. In this work, an international community of research laboratories developed open-source IEEE Std. 1547.1 test scripts. The scripts are used to evaluate grid-support functions – such as constant-power-factor, volt-var, volt-watt, and frequency-watt functions – of several DER devices to the draft standard, EEE1547.1. Sample test results are presented and discussed, and recommendations are offered to improve the draft standard during the balloting process

Shape memory polymer adhesive gripper for pick-and-place applications

Over the past few years, shape memory polymers (SMPs) have been extensively studied in term of their remarkable reversible dry adhesive properties and related smart adhesive applications. However, these exceptional properties of SMPs have not been exploited for pick-and-place applications, which would otherwise advance the robotic manipulation. This work explores the use of SMPs to design an adhesive gripper which pick and place target solid objects relying on reversible dry adhesion of SMP. Compared with common finger or soft grippers, the SMP adhesive gripper interacts with a single surface of a target object for pick-and-place. Furthermore, it is easy and inexpensive to manufacture and applicable to various surfaces since it involves reversible dry adhesion. In this paper, associated physical mechanisms and temperature analyses are studied and conducted. Also, the study includes manufacturing of a dual SMP and a release tip which substantially enhances the adhesion strength and considerably minimizes the releasing force. Finally, the versatility and utility of the SMP adhesive gripper are demonstrated through pick-and-place experiments.LimitedAuthor requested closed access (OA after 2yrs) in Vireo ETD syste

A Shape Memory Polymer Adhesive Gripper for Pick-and-Place Applications

Over the past few years, shape memory polymer (SMP) has been extensively studied in terms of its remarkable reversible dry adhesive properties and related smart adhesive applications. However, its exceptional properties have not been exploited for further opportunities such as pick-and-place applications, which would otherwise advance the robotic manipulation. This work explores the use of an SMP to design an adhesive gripper that picks and places a target solid object employing the reversible dry adhesion of an SMP. Compared with other single surface contact grippers including vacuum, electromagnetic, electroadhesion, and gecko grippers, the SMP adhesive gripper interacts with not only flat and smooth dry surfaces but also moderately rough and even wet surfaces for pick-and-place with high adhesion strength (> 2 atmospheres). In this work, associated physical mechanisms, SMP adhesive mechanics, and thermal conditions are studied. In particular, the numerical and experimental study elucidates that the optimal compositional and topological SMP design may substantially enhance its adhesion strength and reversibility, which leads to a strong grip force simultaneously with a minimized releasing force. Finally, the versatility and utility of the SMP adhesive gripper are highlighted through diverse pick-and-place demonstrations.1

The Removal Performance of an Electrostatic Precipitator at a Manufacturing Site Using a Wet-porous Electrode Array

In this study, to eliminate the ultrafine particles and gaseous pollutants generated in the manufacturing site and supply clean air to the working chamber of the injection molding machine, we analyzed the concentrations and size distributions of ultrafine particles, as well as their chemical components and morphologies, in the injection molding process applied in a machine used for manufacturing disposable medical devices. The concentrations of water-soluble gases such as sulfur dioxide (SO2), which is an undesirable emission, were also measured during the manufacturing process. Furthermore the WPE- ESP (Electrostatic precipitator with wet-porous electrode arrays) was modified and optimized for a mounting system so that it could be applied for the injection molding process that is used to manufacture high-precision devices. The generated ESP system had a high collection efficiency of > 99.5% under laminar flow conditions (flowrate > 0.4 m/s) and removed up to 92.5% the water-soluble SO2 gas that was generated in the manufacturing process. In particular, the proposed system promotes energy efficiency when used over a long period because of the low pressure drop

Is There a Difference in Innovation Performance Depending on the Investment in Each Stage of Development Process? Evidence From Medical Device Industry

Though innovation is essential to achieve competitiveness in the medical device industry, it is difficult for most firms in developing countries to invest sufficient resources in research and development (R&D) activities due to their small firm size. Therefore, it is necessary to evaluate a company’s R&D performance based on the R&D efficiency, which is R&D output to input, rather than the output itself. Although medical device development (MDD) process in the medical device industry is divided into several stages, moreover, the impact of R&D activities in each MDD stage on R&D performance is still unanswered. This study verifies the difference in R&D efficiency according to three business types: both manufacturing and import, manufacturing only, and import only. The effect of the R&D activities in each MDD phase on R&D efficiency is also verified. The results prove that import-only companies tend to achieve higher level of R&D efficiency than firms engaging in manufacturing-only or both manufacturing and import. However, the difference in R&D efficiency between manufacturing-only companies and both manufacturing and import companies has not been verified. Furthermore, it is also verified that the impact of investment in each MDD stage on R&D efficiency varies depending on business types