Energy harvesting technologies that can convert wasted various energy into usable electrical energy have been widely investigated to overcome the limitation of batteries for the powering of IoT sensors and small electronic devices. Hybrid energy harvesting is known as a technology that enhances the output power of single energy harvesting device by housing two or more various energy harvesting mechanisms. In this study, we introduce a hybrid MME (Magneto-Mechano-Electric) generator coupled with the triboelectric effect. Through FEA modeling, four triboelectric materials, including PI (Polyimide), PFA(Teflon), Cu, and Al, were selected and compared with the expected triboelectric potentials. The effect of surface morphology was investigated as well. Among various combination of triboelectric materials and surface morphologies, PFA-Al combination with the surface morphology having nano-scale square projections showed highest output potential under triboelectrification. It is also experimentally confirmed that output voltage and power of the hybrid MME generator with triboelectric material combinations.

A newly proposed T-shape piezoelectric actuator, composed of piezoelectric benders, was designed and studied. This actuator has four legs, and can walk in both forward and backward directions. The piezoelectric actuator has a simple structure and can be easily fabricated. It consists of a piezoelectric bender and a joint. The piezoelectric bender is composed of carbon and ceramic materials. Therefore, there is an advantage in that it can be fabricated on a very small scale. Elliptical displacements of the piezoelectric actuators were analyzed by finite element analysis. Elliptical motion at the tip occurred at two voltages having a 90-degree phase difference. Based on the finite element analysis results, prototype actuators with maximum displacements were fabricated, and the characteristics of their movements were characterized.

Recently, energy harvesting technology is increasing due to the fossil fuel shortages. Energy harvesting is generating electrical energy from wasted energies as sunlight, wind, waves, pressure, and vibration etc. Energy harvesting is one of the alternatives of fossil fuel. One of the energy harvesting technologies, the piezoelectric energy harvesting has been actively studied. Piezoelectric generating uses a positive piezoelectric effect which produces electrical energy when mechanical vibration is applied to the piezoelectric device. Piezoelectric energy harvesting has an advantage in that it is relatively not affected by weather, area and place. Also, stable and sustainable energy generation is possible. However, the output power is relatively low, so in this paper, newly designed honeycomb shaped piezoelectric energy harvesting device for increasing a generating efficiency. The output characteristics of the piezoelectric harvesting device were analyzed according to the change of parameters by using the finite element method analysis program. One model which has high output voltage was selected and a prototype of the honeycomb shaped piezoelectric harvesting device was fabricated. Experimental results from the fabricated device were compared to the analyzed results. After the AC-DC converting, the power of one honeycomb shaped piezoelectric energy harvesting device was measured 2.3[mW] at road resistance 5.1[KΩ]. And output power was increased the number of harvesting device when piezoelectric energy harvesting device were connected in series and parallel.

This paper describes the development of a piezoelectric flextensional transducer, which aims toeffectively degrade the TCE contained in aqueous solution. In order to adjust the 1st flextensionalresonant frequency and output displacement of the flextensional transducer, the effect of the geometricalvariations on performance was analyzed using the finite element analysis (FEM). The results indicatedthat the effect of external shell`s thickness and curvature were most significant, and experimentalfabrication and characterization of a transducer was performed to confirm the results. To prove the capacity to degrade the TCE contained in aqueous solution, 50 and 100 ppm of TCE were prepared in sealed chamber, and investigated the removal rate of TCE through the time and initial concentration.

In this study, novel ultrasonic rotary motor of hexadecagon shape stator was proposed. Statorof the hexadecagon ultrasonic motor was composed of an elastic ring and ceramics. The elastic ring hadsixteen sides and sixteen angular points. Eight ceramics were attached on the outer surface of the eightsides of the ring. When rotor of cylindrical shaft was inserted inside of the ring stator, central lines of thesixteen sides of the stator hold the shaft by the slight pressures(frictions). This slight pressure was apreload of the motor and it could be controlled by radius and thickness of the ring. When two sinusoidalvoltages which have 90 degree phase difference were applied to each four ceramics, elliptical displacementsof inner surface of the ring were obtained. These elliptical displacements of the inner surface rotated theshaft rotor through the frictions. The proposed hexadecagon ultrasonic motor was designed and analyzedby using the finite element method (FEM), depending on materials of the elastic ring. Based on the FEMresults, one model of motor which showed maximum displacement at contact points was chosen andfabricated. And characteristics of the motor were compared with simulated results. When the motor wasfabricated with these results, EL20ET0.5CT0.5CW2 model showed 115[rpm] speed about input voltage of60[Vrms] at 65.6[kHz]. And the maximum torque of 6[gfcm] was obtained. From these results, thehexadecagon shaped ultrasonic motor can be used to actuator for optical device which needs detailedposition control. Also it can be used to medical and portable device by reducing size and weight.

To evaluate whether or not their product is in conformity with its drawing, today`s factories manufacturing rubber and/or plastic products use manual process. In manual conformity inspection process, a person decides conformity as comparing drawing to image of product with his eyes. The manual process is tedious and time-consuming in addition that it is impossible to automatically record various informations related to inspection. To solve such problems, this paper proposes automatic drawing conformity inspection system based on computer vision technologies such as image feature matching and bilinear interpolation. The test results show that proposed system is a lot faster when comparing with manual system.

In a real-time indoor place recognition system using image features detection, specific markers included in input image should be detected exactly and quickly. However because the same markers in image are shown up differently depending to movement, direction and angle of camera, it is required a method to solve such problems. This paper proposes a technique to extract the features of object without regard to change of the object scale. To support real-time operation, it adopts SURF(Speeded up Robust Features) which enables fast feature detection. Another feature of this system is the user mark designation which makes possible for user to designate marks from input image for location detection in advance. Unlike to use hardware marks, the feature above has an advantage that the designated marks can be used without any manipulation to recognize location in input image.

A novel design of a simple square-frame USM (ultrasonic motor) was proposed. The stator of the motor consists of a square-frame shape elastic body and four rectangular plate ceramics. The four ceramics were attached to inner surfaces of the square frame elastic body. The same phase voltages were applied to the ceramics on horizontal surfaces, and 90 degree phase difference voltage were applied to the ceramics on vertical surfaces. To find a model that generates elliptical motion at outside of the stator, the finite element analysis program ATILA was used. The analyzed results were compared to the experimental results. As result, the model EL10EH3ET0.5CL4 which generates the maximum elliptical displacement was chosen by analyzing the resonance mode according to changes in frequency.