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In precision robotic assembly visual sensing techniques have been widely used since they can detect large misalignments and also part's shape at a distance. Develops two novel visual sensing methodologies.

Both systems consist of four components: an inside mirror and an outside mirror, a pair of plane mirrors and a camera with a collecting lens. The difference between the two is that system A adopts a pyramidal mirror configuration, while system B employs a conic one. Owing to this configuration difference, system A can detect three‐dimensional measurements of objects with only one image capture, while in addition to this functionality system B is shown to be capable of detecting two omni‐directional image. The measurement principles are described in detail and compared with each other.

The image acquiring process is shown to easily detect the in situ status of each assembly action, while the recognition method is found to be effective to identify instantaneous misalignment between the peg and the hole. The results obtained from a series of experiments show that the proposed visual sensing methods are an effective means of detecting misalignment between mating parts even in the presence of self‐occlusion.

The proposed sensing methods will dramatically increase the rate of success when actually utilized in assembly processes.

Describes the development of two novel visual sensing methodologies.

The purpose of this paper is to investigate, theoretically and experimentally, a concave mirror‐based fiber optic displacement sensor performance for three‐axes directional measurements.

Mathematical model is constructed based on spherical mirror properties of the concave mirror and the simulated result is found to be in good agreement with the experimental results.

Both theoretical and experimental results show that the focal length and radius of the concave mirror make significant influence to the displacement response. In the x‐axes measurement, six linear slopes are obtained with four of them are located in the vicinity of the position, two times of the focal length. The maximum measurement range of about 20 mm is obtained using a focal length of 10 mm. In the y‐ and z‐axes displacement measurements, the linear range increases as the diameter of concave mirror increases. The longest linear range of 8 mm is achieved at mirror radius of 10 mm.

This is the first demonstration of three axes directional displacement measurements using a concave mirror as a target

The purpose of this paper is to present the need, and a potential solution, for in‐plane routing of optical signals for optical‐enabled circuit boards.

Multimode waveguides and integrated 45° in‐plane mirror structures were made in a low loss acrylate‐based photopolymer using excimer laser ablation. The fabrication of multimode waveguides and mirrors was carried out in a single laser system which minimised alignment issues.

It was established that in‐plane mirror fabrication using laser ablation can be achieved and can potentially be used to define mirrors in waveguides made by other methods such as photolithography.

While the concept (integrated in‐plane mirror) was demonstrated, the viability of its deployment will depend on the results of optical loss measurements for which further research is required.

The paper gives an overview of the design concept and fabrication steps for an in‐plane embedded mirror.

It is a huge technical and engineering challenge to realize the precise assembly of thousands of large optics in high power solid-state laser system. Using the 400-mm aperture-sized transport mirror as a case, this paper aims to present an intelligent numerical computation methodology for mounting performance analysis and modeling of large optics in a high-power laser system for inertial confinement fusion (ICF).

Fundamental principles of modeling and analysis of the transport mirror surface distortion are proposed, and a genetic algorithm-based computation framework is proposed to evaluate and optimize the assembly and mounting performance of large laser optics.

The stringent specifications of large ICF optics place very tight constraints upon the transport mirror’s assembly and mounts. The operational requirements on surface distortion [peak-to-valley and root mean square (RMS)] can be met as it is appropriately assembled by the close loop of assembly-inspection-optimization-fastening. In the end, the experimental study validates the reliability and effectiveness of the transport mirror mounting method.

In the assembly design and mounting performance evaluation of large laser optics, the whole study has the advantages of accurate evaluation and intelligent optimization on nano-level optical surface distortion, which provides a fundamental methodology for precise assembly and mounting of large ICF optics.

To extend to electromagnetism the acoustic wave reflections on time reversal mirrors used in medical imaging, nondestructive testing and underwater acoustics.

Recent works (1993‐2004) analyse the reflection of acoustic waves on time reversal mirror. To perform the same job in electromagnetism, the behaviour of the electromagnetic field tensor under the space and time inversions of the referential is investigated and also, when in addition an exchange of two coordinates exists. All these reflections are supposed obtained from perfect but unconventional mirrors.

Electromagnetic reflections on unconventional mirrors have remarquable features since some of them give birth to a real twin source of the incident source with an opposite polarization.

The techniques used in acoustic to manufacture time reversal mirrors can be used in electromagnetism with possible applications of such mirrors for instance in cameras to avoid reversed photographs but no information on practical realizations has appeared in the open literature.

Extends research on electromagnetism.

The present paper aims to propose a basic current mirror-sensing circuit as an alternative to the traditional Wheatstone bridge circuit for the design and development of high-sensitivity complementary metal oxide semiconductor (CMOS)–microelectromechanical systems (MEMS)-integrated pressure sensors.

This paper investigates a novel current mirror-sensing-based CMOS–MEMS-integrated pressure-sensing structure based on the piezoresistive effect in metal oxide field effect transistor (MOSFET). A resistive loaded n-channel MOSFET-based current mirror pressure-sensing circuitry has been designed using 5-μm CMOS technology. The pressure-sensing structure consists of three identical 10-μm-long and 50-μm-wide n-channel MOSFETs connected in current mirror configuration, with its input transistor as a reference MOSFET and output transistors are the pressure-sensing MOSFETs embedded at the centre and near the fixed edge of a silicon diaphragm measuring 100 × 100 × 2.5 μm. This arrangement of MOSFETs enables the sensor to sense tensile and compressive stresses, developed in the diaphragm under externally applied pressure, with respect to the input reference transistor of the mirror circuit. An analytical model describing the complete behaviour of the integrated pressure sensor has been described. The simulation results of the pressure sensor show high pressure sensitivity and a good agreement with the theoretical model has been observed. A five mask level process flow for the fabrication of the current mirror-sensing-based pressure sensor has also been described. An n-channel MOSFET with aluminium gate was fabricated to verify the fabrication process and obtain its electrical characteristics using process and device simulation software. In addition, an aluminium gate metal-oxide semiconductor (MOS) capacitor was fabricated on a two-inch p-type silicon wafer and its CV characteristic curve was also measured experimentally. Finally, the paper presents a comparative study between the current mirror pressure-sensing circuit with the traditional Wheatstone bridge.

The simulated sensitivities of the pressure-sensing MOSFETs of the current mirror-integrated pressure sensor have been found to be approximately 375 and 410 mV/MPa with respect to the reference transistor, and approximately 785 mV/MPa with respect to each other. The highest pressure sensitivities of a quarter, half and full Wheatstone bridge circuits were found to be approximately 183, 366 and 738 mV/MPa, respectively. These results clearly show that the current mirror pressure-sensing circuit is comparable and better than the traditional Wheatstone bridge circuits.

The concept of using a basic current mirror circuit for sensing tensile and compressive stresses developed in micro-mechanical structures is new, fully compatible to standard CMOS processes and has a promising application in the development of miniaturized integrated micro-sensors and sensor arrays for automobile, medical and industrial applications.

The purpose of the present paper is to propose a full model‐based method for distance‐mapping calibration for the non‐SVP (non‐single viewpoint) catadioptric camera of the soccer robot. The method should be easy to operate, efficient, accurate, and scalable to fit larger field sizes.

The distance‐mapping model was first constructed based on the imaging principle. The authors then calibrated the internal parameters using the mirror boundary and used the mirror center to choose the correct pose from two possible solutions. The authors then proposed a three‐point method based on a unique solution case of the non‐SVP P3P (perspective‐three‐point) problem to solve the external parameters. Lastly, they built the distance mapping by back‐projection.

The simulation experimental results have shown that the authors' method is very accurate even when there is severe misalignment between the mirror and the camera and that all calibration operations, except the calibration of a standard camera, can be completed in 1 min. The result of the comparison with the traditional calibration method shows that the authors' method is superior to the traditional method in terms of accuracy and efficiency.

The proposed calibration method is scalable to larger fields because it only uses the boundary of the mirror and three feature points on the field, and does not need additional calibration objects. Additionally, an automatic calibration method that can be used during the game can be easily developed based on this method. Moreover, the proposed mirror‐pose‐selection method and a unique solution to the non‐SVP P3P problem are especially useful for a non‐SVP catadioptric camera.

This qualitative study was an exploration on the process of self-reflection on identity. The purpose of this paper is to see how mirrors could be used as a therapeutic tool and a meta-physical bridge to one's inner consciousness.

An intergenerational expressive arts group (n=12) was organized around the question of identity. Following an open-discussion around the topic of identity, participants were asked to decorate a mirror with words, images, and/or symbols while reflecting on the question, “Who am I?” A post-session interview was conducted regarding participant's experiences during the creative process.

The results indicated that mirrors can be used to connect to one's inner thoughts and feelings on the question of identity. Three core themes in the process of self-reflection on identity were revealed which included introspection and self-concern, connection and attachment to something or someone other than self, and taking action to help others.

This study was limited not only in size, but also in cultural diversity and disparity of age range. Although this study was limited, it provided a useful indicator for identifying core themes in the process of self-reflection on identity.

While there have been no studies on the therapeutic use of mirrors as a tool for self-reflection and limited intergenerational studies with pre-adolescent and adolescent students and older adults, results from this study will add to the body of expressive arts literature by providing a new metaphor for mirrors as a therapeutic tool for self-reflection on identity.

The purpose of this paper is to analyse the interaction between a profit maximising mortgagor and a newcomer to a mortgage market with Bertrand competition where the newcomer has a populistic entry strategy and undercuts mortgage market rates. The intention of the paper is to relate the populistic entry strategy to mortgage market characteristics and the strategic market position of both the established mortgagor and the newcomer in question.

The paper analyses a mortgage market by combining the behaviour of a profit maximising mortgagor with that of a newcomer to the mortgage market which has a populistic entry strategy and does not maximise profits. The short-run market solution provides comparative statics on the strategic market position of both the established mortgagor and the newcomer to the mortgage market during the entry phase both related to product differentiation and to price mirroring and undercutting of mortgage rates.

The model finds a mortgage market solution where a lower mortgage rate helps the newcomer gain a customer base. As the newcomer's strategy to mirror prices makes it unable to pass-through funding cost to its mortgage rate, the strategy is unsustainable over time. The established mortgagor has a strategically beneficial position as the mortgage market rates only relate to its funding cost. Unless the newcomer has a funding cost advantage, the established mortgagor has a higher interest rate margin. Differentiation impacts the newcomers’ interest rate margin positively. If the newcomer lacks a funding cost advantage, there is a critical mirroring rate that ensures it a higher interest rate margin. The higher the newcomers’ own funding cost, the higher is the upper bound for price mirroring, relating market entry to a small undercutting of mortgage rates and a mortgage market with weak competition. The funding cost of the established mortgagor pulls pricing in the opposite direction, allowing for a lower mirroring rate and tougher mortgage market competition during entry.

The paper aims to contribute to the understanding of market equilibrium in the absence of profit maximising behaviour. Framing a mortgage market in terms of a duopoly where a newcomer enters with a populistic entry strategy offering a lower mortgage rate and a mortgage product with a different loan-to-value (LTV) ratio, a novel mortgage market case comes about. The populistic entry strategy produces an augmented reaction curve, crucial for the mortgage market rates.

The purpose of this paper is to properly calibrate the laser tracking system (LTS) prior to using it for metrology and improving the measuring accuracy of LTS.

A kinematics model that describes not only the motion but also geometric variations of LTS is developed. Effects of tracking mirror mechanism dimension errors on measured coordinates and target reflector alignment errors on sensor reading are investigated.

Through error analysis of the proposed model, it is claimed that gimbals axis misalignments and tracking mirror center offset are the key contributors to measure errors of LTS. Intensive simulation studies are conducted to check the validity of the theoretical results and various practical issues are also explored in the simulations. The simulation results demonstrate that under realistic conditions the 10‐parameter model is the minimal and complete model.

This model, together with its error model which is also presented in this paper, can be used for design, calibration, and control of LTS.

This paper develops a kinematics model that describes not only the motion but also geometric variations of LTS, and demonstrates that gimbals axis misalignments and tracking mirror center offset is the key contributor to measuring errors of LTS.