Manipulation Scheme Research Articles

Position and inclination control of a passive disk based on cyclic motion generation

We propose a position and inclination controlling method for a passive object using an active plate. Previously, we proposed a novel manipulation scheme that can control a passive object’s orientation using an active plate. In the work, stable plate cyclic motion is designed and inclination control of the object is realized. However, the object’s position is not considered, so there is a possibility that the object could move. Using our plate trajectory design we can control not only the passive object’s inclination but also its position. We verify that the designed plate motion can control both the object’s inclination and its position through dynamics simulation. A stability analysis around a fixed point is conducted using a Poincaré return map, demonstrating that fixed points are asymptotically stable.

Adaptive Neural Output Feedback Control for Uncertain Robot Manipulators with Input Saturation

This paper presents an adaptive neural output feedback control scheme for uncertain robot manipulators with input saturation using the radial basis function neural network (RBFNN) and disturbance observer. First, the RBFNN is used to approximate the system uncertainty, and the unknown approximation error of the RBFNN and the time-varying unknown external disturbance of robot manipulators are integrated as a compounded disturbance. Then, the state observer and the disturbance observer are proposed to estimate the unmeasured system state and the unknown compounded disturbance based on RBFNN. At the same time, the adaptation technique is employed to tackle the control input saturation problem. Utilizing the estimate outputs of the RBFNN, the state observer, and the disturbance observer, the adaptive neural output feedback control scheme is developed for robot manipulators using the backstepping technique. The convergence of all closed-loop signals is rigorously proved via Lyapunov analysis and the asymptotically convergent tracking error is obtained under the integrated effect of the system uncertainty, the unmeasured system state, the unknown external disturbance, and the input saturation. Finally, numerical simulation results are presented to illustrate the effectiveness of the proposed adaptive neural output feedback control scheme for uncertain robot manipulators.

Zeroing dynamics based motion control scheme for parallel manipulators

Zeroing dynamics (ZD), as a powerful method proposed for time-varying problems solving, has found successful applications in motion control of serial manipulators. Compared with serial manipulators, parallel manipulators possess some attractive advantages such as high carrying capacity and high operation accuracy. However, the inherent differences between parallel and serial manipulators set great difficulties on the applications of ZD to the control of parallel manipulators. Making progress along this direction, the first ZD based motion controller of parallel manipulators is proposed and the design procedure of the ZD based scheme is presented. As a typical application, the proposed scheme is utilised to control a Stewart platform for tracking a quatrefoil-shaped path, which illustrates the effectiveness of the ZD based scheme.

Transfer Pricing in Argentina 1932-2015

This document provides a review of the Argentine tax authority’s structure for dealing with transfer pricing in Argentina; a chronological review of the legislative transfer pricing framework; and a very extensive listing of the transfer pricing cases that have reached different court levels. The document also summarises some of the difficulties encountered in relation to the application of the arm’s length principle in Argentina; coordination with foreign tax authorities; and the regulatory changes expected following the reports resulting from the G20/OECD BEPS Action Plan. Argentine transfer pricing legislation has taken several turns over time, moving from a more restrictive pricing of exports and imports for income tax purposes to what is today internationally known as the Sixth Method for commodity valuation; and from an application of what is locally known as the ‘economic reality’ principle, a principle attempting to consider the economic substance over the contractual forms, to a transplantation into local legislation of the Organisation for Economic Co-operation and Development’s Transfer Pricing Guidelines based on the arm’s length principle. The consequences of these regulatory changes have been that lately more and more cases are being disputed at different court levels, and tax authorities seem to find it increasingly difficult to challenge multinational entities’ transfer pricing manipulation schemes and support their arguments in courts of law.

Experimental Realization of a Thermal Squeezed State of Levitated Optomechanics.

We experimentally squeeze the thermal motional state of an optically levitated nanosphere by fast switching between two trapping frequencies. The measured phase-space distribution of the center of mass of our particle shows the typical shape of a squeezed thermal state, from which we infer up to 2.7dB of squeezing along one motional direction. In these experiments the average thermal occupancy is high and, even after squeezing, the motional state remains in the remit of classical statistical mechanics. Nevertheless, we argue that the manipulation scheme described here could be used to achieve squeezing in the quantum regime if preceded by cooling of the levitated mechanical oscillator. Additionally, a higher degree of squeezing could, in principle, be achieved by repeating the frequency-switching protocol multiple times.

Cooling phonons with phonons: Acoustic reservoir engineering with silicon-vacancy centers in diamond

We study a setup where a single negatively-charged silicon-vacancy center in diamond is magnetically coupled to a low-frequency mechanical bending mode and via strain to the high-frequency phonon continuum of a semi-clamped diamond beam. We show that under appropriate microwave driving conditions, this setup can be used to induce a laser cooling like effect for the low-frequency mechanical vibrations, where the high-frequency longitudinal compression modes of the beam serve as an intrinsic low-temperature reservoir. We evaluate the experimental conditions under which cooling close to the quantum ground state can be achieved and describe an extended scheme for the preparation of a stationary entangled state between two mechanical modes. By relying on intrinsic properties of the mechanical beam only, this approach offers an interesting alternative for quantum manipulation schemes of mechanical systems, where otherwise efficient optomechanical interactions are not available.

Slipping through the Cracks: Detecting Manipulation in Regional Commodity Markets

Between 2010 and 2014, the regional price of aluminum in the United States (Midwest premium) increased threefold. We argue that the Midwest premium was likely manipulated during this period through the exercise of market power in the aluminum storage market. We first use a difference-in-differences model to show that there was a statistically significant increase of $0.07 per pound in the regional price of aluminum relative to the regional price of a production complement, copper. We then use several instrumental variables to show that this increase was driven by a single financial company’s accumulation of an unprecedented level of aluminum inventories in Detroit. Since this scheme targeted the regional price of aluminum, regulators who monitored only spot and futures prices would not have noticed anything peculiar. We therefore present an algorithm for real-time detection of similar manipulation schemes in regional commodity markets. The algorithm confirms the existence of a structural break in the U.S. aluminum market in late 2011. Using the algorithm, regulators could have detected the scheme as early as December 2012, more than six months before it was publicized by an article in The New York Times. We also apply the algorithm to another suspected case of regional price manipulation in the European aluminum market and find a similar break in 2011, suggesting the scheme may have been implemented beyond the United States.

Mathematical modeling of the dynamics of manipulation system for mobile transport and technological machine with reference to the elasticity of elements

The approaches to modeling the dynamics of mobile manipulators of transport and technological machines with reference to the elastic compliance of elements are shown. The equations of motion of the manipulator units are recorded using the method of Lagrange multipliers. As the main origin for each element were taken four Rodrigues-Hamilton parameters, coordinates of the element position as absolutely rigid body and elastic movements. The equations take into account the impact of external and internal elastic and quadratic forces. Internal elastic forces are calculated on the basis of the stiffness matrix, which formation is made through calculation of the manipulator by finite element method. To set the join couplings the required number of constraint equations is built. The methods of creating of widespread kinematic schemes of manipulators of cylindrical and prismatic joints using set of constraints involving mutual perpendicular vectors, which belong to articulated elements. Using the developed model the dynamics of articulated manipulator crane ACT-4-A was calculated. It was found that the inclusion of elements elasticity reveals oscillatory behavior of the kinematic and power factors of the process and, thus, increase the adequacy of modeling of manipulation system operation during machine use. Elastic elements causes their oscillations with a frequency, which is commensurable with the first lower natural frequency of metal manipulation system itself, that indicates the desirability of its test for the absence of resonance and, if necessary, the development of positive measures to improve the dynamic reliability of the manipulation system. It has been shown that to calculate manipulators for some machines the chassis dynamics should be taken into account.

Milestones Toward Majorana-Based Quantum Computing

We introduce a scheme for preparation, manipulation, and readout of Majorana zero modes in semiconducting wires with mesoscopic superconducting islands. Our approach synthesizes recent advances in materials growth with tools commonly used in quantum-dot experiments, including gate-control of tunnel barriers and Coulomb effects, charge sensing, and charge pumping. We outline a sequence of milestones interpolating between zero-mode detection and quantum computing that includes (1) detection of fusion rules for non-Abelian anyons using either proximal charge sensors or pumped current; (2) validation of a prototype topological qubit; and (3) demonstration of non-Abelian statistics by braiding in a branched geometry. The first two milestones require only a single wire with two islands, and additionally enable sensitive measurements of the system's excitation gap, quasiparticle poisoning rates, residual Majorana zero-mode splittings, and topological-qubit coherence times. These pre-braiding experiments can be adapted to other manipulation and readout schemes as well.

Optical pulling using evanescent mode in sub-wavelength channels

Optical evanescent wave in total internal reflection has been widely used in efficient optical manipulation, where the object is trapped by the intrinsic intensity gradient of the evanescent wave while transported by the scattering force along the orthogonal direction. Here, we propose a distinct optical manipulation scheme using the attenuated modes in subwavelength optical channels, where both the trapping and transportation forces are along the channel direction. We create such a mode in a sub-wavelength photonic crystal waveguide and quantitatively obtain the net pushing and pulling forces, which can overcome the Brownian motion within a critical length. Due to the presence of the physical channel, subwavelength trapping on the transverse direction is natural, and manipulation along bend trajectories is also possible without the assistance of the self-acceleration beams provided a channel is adopted. This optical manipulation method can be extended to any other channels that support attenuation mode, and may provide an alternate way for flexible optical manipulation.

A frequency-control particle separation device based on resultant effects of electroosmosis and dielectrophoresis

Particle separation plays an important role in microfluidic sample preparation for various biomedical applications. In this paper, we report a particle manipulation and separation scheme using a microfluidic device based on low-volume/low-voltage electrokinetic frequency modulation. Utilizing a circular micro-electrode array, both electroosmosis and dielectrophoresis can be contributed to manipulate particles in the device by controlling the frequency of applied sinusoidal travelling wave signals. Theoretical simulations based on finite-element methods are employed to establish fundamental understanding of the developed scheme. For experimental demonstration, polystyrene beads (6 μm in diameter) and human promyelocytic leukaemia cells (HL-60) are used to validate the frequency-modulation effect. Furthermore, different diameter polystyrene beads (6 μm and 10 μm in diameter) are mixed to show potentials of precise particle separations (∼90% efficiency) by the reported frequency-controlled electrokinetic device. The developed technique can be exploited as an actuation scheme and particle manipulation method for microfluidic sample preparations of low ionic concentration samples.

Frequency-domain waveform modelling and inversion for coupled media using a symmetric impedance matrix

To simulate the seismic signals that are obtained in a marine environment, a coupled system of both acoustic and elastic wave equations is solved. The acoustic wave equation for the fluid region simulates the pressure field while minimizing the number of degrees of freedom of the impedance matrix, and the elastic wave equation for the solid region simulates several elastic events, such as shear waves and surface waves. Moreover, by combining this coupled approach with the waveform inversion technique, the elastic properties of the earth can be inverted using the pressure data obtained from the acoustic region. However, in contrast to the pure acoustic and elastic cases, the complex impedance matrix for the coupled media does not have a symmetric form because of the boundary (continuity) condition at the interface between the acoustic and elastic elements. In this study, we propose a manipulation scheme that makes the complex impedance matrix for acoustic–elastic coupled media to take a symmetric form. Using the proposed symmetric matrix, forward and backward wavefields are identical to those generated by the conventional approach; thus, we do not lose any accuracy in the waveform inversion results. However, to solve the modified symmetric matrix, LDLT factorization is used instead of LU factorization for a matrix of the same size; this method can mitigate issues related to severe memory insufficiency and long computation times, particularly for large-scale problems.

Design and construction of a reaction system for cyclohexane catalytic aerobic oxidation using cobalt in SBA-3

In this work, a reaction system was designed and built to carry out the aerobic oxidation reaction of cyclohexane to obtain cyclohexanol and cyclohexanone using cobalt incorporated in SBA-3 materials as catalysts, which were tested on this reaction using the system. The design comprehended the determination of the wall thickness of the reactor in order for it to perform at 140°C and 8 MPa. It also included the installation of an aeration system which also used to agitate the catalyst in the fluid bulk, the installation of temperature control and monitoring components, a scheme of delivery, measuring and manipulation of airflow, and a condensation of cyclohexane compound at the exit of the reactor. The reaction was carried out at the mentioned conditions during one hour, using two cobalt incorporated SBA-3 catalysts, synthetized previously by doping and incipient wetness impregnation respectively, in a theoretical molar Si/Co ratio of 25. The resulting conversions obtained with the materials were 0.81% and 0.20% for the doped and the impregnated material respectively.

Dynamic Manipulation of Charged Lipids in Model Membrane for Bio-Microarrays.

We describe the dynamic manipulation of the charged lipids in a confined geometry where two dispersive factors arising from the random diffusion-based Brownian motion and the field-induced drift of target lipids compete with each other. It is found that the lateral distribution of the target lipids is well controlled through a combined effect of an external electric field and the geometric restrictions by the confinement. The dynamic manipulation scheme for the charged lipids in two-dimension would be useful for understanding the spatial organization of membrane components in a supported lipid membrane mimicking a real cell membrane and for producing membrane-based microarrays.

Continuity of Monolayer-Bilayer Junctions for Localization of Lipid Raft Microdomains in Model Membranes.

We show that the selective localization of cholesterol-rich domains and associated ganglioside receptors prefer to occur in the monolayer across continuous monolayer-bilayer junctions (MBJs) in supported lipid membranes. For the MBJs, glass substrates were patterned with poly(dimethylsiloxane) (PDMS) oligomers by thermally-assisted contact printing, leaving behind 3 nm-thick PDMS patterns. The hydrophobicity of the transferred PDMS patterns was precisely tuned by the stamping temperature. Lipid monolayers were formed on the PDMS patterned surface while lipid bilayers were on the bare glass surface. Due to the continuity of the lipid membranes over the MBJs, essentially free diffusion of lipids was allowed between the monolayer on the PDMS surface and the upper leaflet of the bilayer on the glass substrate. The preferential localization of sphingomyelin, ganglioside GM1 and cholesterol in the monolayer region enabled to develop raft microdomains through coarsening of nanorafts. Our methodology provides a simple and effective scheme of non-disruptive manipulation of the chemical landscape associated with lipid phase separations, which leads to more sophisticated applications in biosensors and as cell culture substrates.

Simultaneous fault diagnosis for robot manipulators with actuator and sensor faults

This paper studies a model-based fault detection and isolation (FDI) scheme for robot manipulators with actuator and sensor faults. Without adding redundant joint sensor measurements, the multiple faults simultaneously occurring in the actuators and sensors of the manipulator are detected, estimated and isolated. Considering Lipschitz-like nonlinearities and modeling uncertainties, a nonlinear adaptive observer is presented to estimate the faulty parameters with a pre-specified estimation error bound. The performances of the proposed FD scheme, including the robustness of observers to the uncertainties, the accuracy of fault estimation and the rapidity of fault diagnosis, are rigorously analyzed. The proposed approach is verified by a simulation of Integrated Motion Inc. (IMI) two-link, revolute, direct-drive robot manipulator.

Integrated Microfluidic Isolation of Aptamers Using Electrophoretic Oligonucleotide Manipulation.

We present a microfluidic approach to integrated isolation of DNA aptamers via systematic evolution of ligands by exponential enrichment (SELEX). The approach employs a microbead-based protocol for the processes of affinity selection and amplification of target-binding oligonucleotides, and an electrophoretic DNA manipulation scheme for the coupling of these processes, which are required to occur in different buffers. This achieves the full microfluidic integration of SELEX, thereby enabling highly efficient isolation of aptamers in drastically reduced times and with minimized consumption of biological material. The approach as such also offers broad target applicability by allowing selection of aptamers with respect to targets that are either surface-immobilized or solution-borne, potentially allowing aptamers to be developed as readily available affinity reagents for a wide range of targets. We demonstrate the utility of this approach on two different procedures, respectively for isolating aptamers against a surface-immobilized protein (immunoglobulin E) and a solution-phase small molecule (bisboronic acid in the presence of glucose). In both cases aptamer candidates were isolated in three rounds of SELEX within a total process time of approximately 10 hours.

Harvesting, Coupling, and Control of Single-Exciton Coherences in Photonic Waveguide Antennas.

We perform coherent nonlinear spectroscopy of individual excitons strongly confined in single InAs quantum dots (QDs). The retrieval of their intrinsically weak four-wave mixing (FWM) response is enabled by a one-dimensional dielectric waveguide antenna. Compared to a similar QD embedded in bulk media, the FWM detection sensitivity is enhanced by up to 4 orders of magnitude, over a broad operation bandwidth. Three-beam FWM is employed to investigate coherence and population dynamics within individual QD transitions. We retrieve their homogenous dephasing in a presence of low-frequency spectral wandering. Two-dimensional FWM reveals off-resonant Förster coupling between a pair of distinct QDs embedded in the antenna. We also detect a higher order QD nonlinearity (six-wave mixing) and use it to coherently control the FWM transient. Waveguide antennas enable us to conceive multicolor coherent manipulation schemes of individual emitters.

Transport studies of LPA electron beam towards the FEL amplification at COXINEL

Laser Plasma Acceleration (LPA) [1] is an emerging concept enabling to generate electron beams with high energy, high peak current and small transverse emittance within a very short distance. The use of LPA can be applied to the Free Electron Laser (FEL) [2] case in order to investigate whether it is suitable for the light amplification in the undulator. However, capturing and guiding of such beams to the undulator is very challenging, because of the large divergence and high energy spread of the electron beams at the plasma exit, leading to large chromatic emittances.A specific beam manipulation scheme was recently proposed for the COXINEL (Coherent X-ray source inferred from electrons accelerated by laser) setup, which makes an advantage from the intrinsically large chromatic emittance of such beams [3]. The electron beam transport is studied using two simulation codes: a SOLEIL in-house one and ASTRA [4]. The influence of the collective effects on the electron beam performance is also examined.

Approach to the Study of Kinematics and Modeling Grip of 22 DOF Anthropomorphic Gripping Manipulator

The results of analysis and study the kinematic model of the anthropomorphic arm with 22 degrees of freedom are given. Describes how to use the package GraspIt! virtual simulation and experimental study of the grasping efficiency of various items. Applications submitted technique enables to compare different versions of kinematic schemes of manipulators and to determine the adequacy of the choice of a particular kinematic scheme for the optimal grasp of a known set of objects. This approach is relevant in the development of manipulators grip, especially in the presence of restrictions on the number of controlled degrees of freedom. For example, when developing bionic prostheses hands actual task of reducing weight and, correspondingly, the number of degrees of freedom. The paper compared the two kinematic schemes to capture the geometric primitives example, so-called human scheme - when the thumb is opposed to the little finger, and monkey scheme - when the thumb is opposed to the middle finger. It is shown that to perform the grasp of large objects appropriate to use human scheme.