Browsing by Author "Cheng, Chiao-Hua"

Now showing 1 - 11 of 11

3D-Printed Linear Positioner with Micrometer Accuracy
(2017-01-01)
Kuo, Yin-Yen
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Cheng, Chiao-Hua
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Hung, Shao-Kang
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機械工程學系
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Department of Mechanical Engineering
This article presents a positioner, whose flexure main body is made by a commercial 3D printer. Using this method, manufacturing a positioner can be cost efficient and much easier to customize. Integrating a laser displacement sensor, an electromagnetic actuator, and a feedback controller, this positioning system has 100 micron translational stroke with 1 micron resolution. Experiments also demonstrate sinusoidal motions at different frequencies. Using the method developed by this article, micro-positioners with customized specifications can be implemented rapidly, iteratively, and cost-effectively.
A Piezoelectric Two-Degree-of-Freedom Nanostepping Motor with a Positioning Sensor
(2018-01-01)
Cheng, Chiao-Hua
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Hung, Shao-Kang
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機械工程學系
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Department of Mechanical Engineering
The design of the proposed piezoelectric two-degree-of-freedom nanostepping motor is driven by the principle of stick-slip. The proposed design not only improves the control of clamping force when the stick-slip cycle is working but adds a position sensing detector (PSD) to record translational distance and rotational angle simultaneously. In general, one degree of freedom needs one sensor to record position information, but a PSD can measure two degrees of freedom simultaneously in this paper. Due to the photosensing element PSD, more applications can be applied in future, such as feedback control for precise positioning.
A Piezoelectric Two-Degree-of-Freedom Nanostepping Motor With Parallel Design
(2016-08)
Cheng, Chiao-Hua
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Hung, Shao-Kang
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機械工程學系
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Department of Mechanical Engineering
This letter proposes a parallel design for a piezoelectric two-degree-of-freedom nanostepping motor, which performs translation or rotation while its two piezoelectric elements are driven in-phase or out-of-phase electrically. Compared to serialmechanism, parallel designs are more compact, stiffer, and have better dynamical characteristics. Experimental results show that this device works stably. The stepping resolution/stroke values of translation and rotation are 100 nm/6 mm and 0.04 degrees/infinite, respectively.
A range-extended displacement sensor using a quartz tuning fork
(2010)
Lu, Yi
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Cheng, Chiao-Hua
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Chen, Li-Kang
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Hung, Shao-Kang
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機械工程學系
A quartz tuning fork is a kind of piezoelectric resonators. Quartz tuning forks can be modified as sensors to measure various properties, such as force, acceleration, displacement, and many other ones. A method to extend the measurable range of a quartz tuning fork based displacement sensor is devised in this paper. The experimental results demonstrate that the linear measurable range of the proposed displacement sensor is 17.6 mu m.
Automatic assembly of quartz tuning fork and microcantilever
(2012)
Cheng, Chiao-Hua
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Chen, Jian-Hua
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Shieh, Jen-Yu
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Hung, Shao-Kang
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機械工程學系
Conventional atomic force microscopes (AFMs) detect microcantilever deflection using an optical lever system. However, the complex mechanism of the optical lever system and the alignment of the laser spot on the microcantilever prevent such AFM systems from scanning large samples. AFM systems using a quartz tuning fork (QTF) as a force sensor have been proven feasible, and enhance compactness of the AFM system. This paper presents the automatic assembly of the QTF sensor and the microcantilever of commercial AFM probe using a visual servo method.
Automatic-Patterned Sapphire Substrate Nanometrology Using Atomic Force Microscope
(2015-03-01)
Hung, Shao-Kang
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Cheng, Chiao-Hua
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Chen, Cheng-Lung
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機械工程學系
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Department of Mechanical Engineering
Light emitting diodes become brighter because of the contribution of patterned sapphire substrates (PSS). The dimensions of PSS crucially affect its performance. The most suitable instrument to measure PSS is atomic force microscope, which provides three-dimensional surface profiles. This paper proposes an automatic method to analyze AFM-collected raw data and produce characteristic parameters of PSS, including height, diameters, pitch, and side angles. Experimental results show that this method has good repeatability of 1.2 and 6.3 nm on measuring height and bottom diameter, respectively. This nanometrology method will be extensively applicable for similar nanostructures with periodic patterns.
Design and Analysis of a 2-DOF Planar Nano-positioner with Low Parasitic Rotation
(2014)
Lin, Hung-Ruei
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Hung, Shao-Kang
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Cheng, Chiao-Hua
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機械工程學系
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Department of Mechanical Engineering
This paper presents the design processes and performance of a new piezoactuated nano-positioner with low parasitic rotation. The flexure-based stage is composed of two symmetric flexure guiding mechanisms and two piezo stack actuators (PSAs) which have a 45 degree angle with X and Y directions. By analyzing the layout of the stage with kinematics and finite element analysis (FEA) results, it shows that this novel design offers a characteristic of low parasitic rotation. Analytical models of PSAs and stage are derived to assess the performances and to decide the parameters of geometry sizes of the hinge and the stage, total stroke, maximum von-Mises stress, and lifetime. A prototype of the stage is then fabricated, and its performances are tested. Two laser displacement sensors and PID control method are used to achieve a feedback control of the system. Experimental results reveal that the stage has stroke of 500 mu m x 500 mu m, resolution of 10 nm, and maximum parasitic rotation of 0.48 arc sec under stroke of +/- 50 mu m.
Design and quasi-static characteristics study on a planar piezoelectric nanopositioner with ultralow parasitic rotation
(2015-10-01)
Lin, Hung-Ruei
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Cheng, Chiao-Hua
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Hung, Shao-Kang
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機械工程學系
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Department of Mechanical Engineering
This paper presents a particular mechanism design which is inherently inclined to have no parasitic rotation. The flexure-based stage comprises symmetric flexure guiding mechanism and two piezoelectric stack actuators. The layout of the stage is evaluated by finite element analysis, and the results indicate that the proposed design exhibits ultralow parasitic rotation. A prototype of the stage is then fabricated, and its performance is tested. Experimental results show that the stage has a stroke of 500 mu m x 500 mu m and the crosstalk is less than 1%. The maximum parasitic rotation is +/- 1.2 arcsec at a stroke of 500 mu m. (C) 2015 Elsevier Ltd. All rights reserved.
Design of a dual-probe profilometer
(2014)
Cheng, Chiao-Hua
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Hung, Shao-Kang
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Lin, Chih-Hsien
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機械工程學系
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Department of Mechanical Engineering
This paper proposes a design of a dual-probe profilometer, which successfully utilizes a compensation method with two probe modules to scan a 200 nm step height standard sample with 5% scanning error. Compared with traditional profilometers, this design possesses high scanning precise performance without using large and heavy optical flats to increase the flatness when sample stage is moving. The experimental results show the compensation method is valid and can be applied in nano-scale scanning.
The design and characteristic research of a dual-mode inertia motor
(2011)
Cheng, Chiao-Hua
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Hung, Shao-Kang
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機械工程學系
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Department of Mechanical Engineering
The design of a dual-mode inertia motor involves an actuator that can generate translational and rotational motion without connecting the actuators serially. Traditionally, translational or rotational actuators should be stacked serially to have multi-axis degrees-of-freedom. The experimental results of this study display performance characteristics such as linearity, resolution, velocity and the most excellent operating frequency.
Transforming an Optical Pick-up-Head into an Accelerometer With UltraHigh Sensitivity
(2014-03-01)
Hung, Shao-Kang
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Cheng, Chiao-Hua
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Chiang, Ming-Li
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Chieh, Jih-Wei
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機械工程學系
This paper proposes an accelerometer based on a commercial optical pick-up-head (PUH). An optical PUH is used to be part of an accelerometer by transforming the astigmatic measuring mechanism, the suspending wires, and the objective lens as the displacement sensor, the spring, and the seismic mass, respectively. Instead of adding an extra mass-damper-spring subsystem into the system in previous works, in our design we utilize the four suspending metal wires and the objective lens in an optical PUH. Thus, no extra component is needed and the system is more compact and easy to implement. Experimental results demonstrate that this cost-effective accelerometer has excellent linearity, ultrahigh sensitivity of 114 V/g, and an operating frequency of 20 Hz.