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A new measurement device is proposed for the calibration of parallel manipulators that can be used to indentify all kinematic parameters with partial pose measurements. The device while restricting the motion of the end-effector to five degree-of-freedom measures three components of posture. A study is performed for a six degree-of-freedom fully parallel Hexa Slide Manipulator. Intrinsic inaccuracies of the measurement device are modeled with two additional identification parameters. Computer simulations show that all parameters, including the additional parameters, can be identified. Results show a significant error reduction, even with noisy measurements, and reveal that the identification is robust against errors in initial guess.

A novel adaptive electrode fabrication method using optically self-selected interfacial adhesion between a laser-processed metal layer and polymer film is introduced to fabricate cost-effectively a high-resolution arbitrary electrode with high conductivity. The quality is close to that from vacuum deposition on a highly heat sensitive polymer film, with active response to various design requirements. A highly conductive metal film (resistivity: 3.6 μΩ cm) below a 5 μm line width with a uniform stepwise profile and mirror surface quality (R(rms) : 5-6 nm) is fabricated on a cheap polymer film with a heat resistance limit of below 100 °C. Severe durability tests are successfully completed without using any adhesion promoters. Finally, a highly transparent and conductive electrode with a transparency above 95% and sheet resistance of less than 10 Ω sq⁻¹ is fabricated on a polymer film and on glass by using this method. These results can help realize a potential high-throughput, low-cost, solution-processable replacement for transparent conductive oxides.

This paper suggests the target tracking method improved for the collaboration of the quad rotor type UAV (Unmanned Aerial Vehicle) and omnidirectional Unmanned Ground Vehicle. If UAV shakes or UGV moves rapidly, the existing method generates a phenomenon that the tracking object loses the tracking target. To solve the problems, we propose an algorithm that can track continually when they lose the target. The proposed algorithm stores the vector of the landmark. And if the target was lost, the control signal was inputted so that the landmark could move continuously to the direction running out. Prior to the experiment, Proportional and integral control were used in 4 motors in order to calibrate the Heading value of the omnidirectional mobile robot. The landmark of UGV was recognized as the camera adhered to UAV and the target was traced through the proportional-integralderivative control. Finally, the performance of the target tracking controller and proposed algorithm was evaluated through the experiment.

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The present paper describes the advancement of displacement potential approach in relation to solution of plane problems of structural mechanics with mixed mode of boundary conditions. Both the conditions of the plane stress and the plane strain are considered for analyzing the displacement and stress fields of the structural problem. Using the finite difference technique based on the present displacement potential approach for the case of the plane stress and the plane strain conditions, firstly an elastic cantilever beam subjected to a pure shear at its tip is solved and these two solutions (plane stress and plane strain) are compared with Timoshenko and Goodier cantilever beam bending solutions (Theory of elasticity, 2nd edn. McGraw-Hill, New York, 1951); secondly the above-mentioned displacement potential approach for the case of the plane stress and the plane strain conditions are applied to solve a one-end fixed square plate subjected to a combined loading at its tip. Effects of plane stress and plane strain on the elastic field of the plate are discussed in a comparative fashion. Limitations of Timoshenko and Goodier cantilever beam bending solutions (Theory of elasticity, 2nd edn. McGraw-Hill, New York, 1951) over the displacement potential approach for the case of the plane stress and the plane strain conditions are not only discussed but also the superiority of the present displacement potential approach for the case of the plane stress and the plane strain conditions are reflected in the present research work.

We report a study on monocrystalline nickel thin films using the atomic force microscope (AFM) based scratching process to understand the associated wear mechanism. As for the nano level fabrication, better understanding of abrasive wear mechanism is a prerequisite. A three-dimensional molecular dynamics (MD) study has been performed and we have used a new parameter wear volume to distinguish between different wear zones. A reduced number of zones have been proposed to understand the wear mechanism during nanoscratching process. Also, centrosymmetry parameter has been used to validate the findings.

The permanent residual strain in aluminum (Al) alloy foams induced by compressive fatigue gradually increases with the increasing number of loading cycles. Consequently, the progressive shortening of Al-alloy foam degrades the dynamic material performance by the failure and ratcheting of multi-cells in the foam. In this paper, the dynamic properties of Al-alloy foams damaged by compressive fatigue were studied. The beam specimens with various residual strains were made by cyclic compression-compression stress. The dynamic bending modulus and loss factor were evaluated by using a beam transfer function method. As a result, the dynamic bending stiffness of Al-alloy foam turned out to be decreased due to damage while the loss factor was improved because of the increasing energy dissipation of such factors as cracked cell walls formed during the shortening process of the foam. The loss factor shows a manifest dependence on the fatigue residual strain.