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A New Qim-Based Image Watermarking Method And System, Wenming Lu, Wanqing Li, Reihaneh Safavi-Naini, Philip O. Ogunbona
A New Qim-Based Image Watermarking Method And System, Wenming Lu, Wanqing Li, Reihaneh Safavi-Naini, Philip O. Ogunbona
Associate Professor Wanqing Li
Embedding capacity, distortion and resilience to attacks are three key indicators to the performance of any image watermarking systems. Study has shown that Quantization Index Modulation (QIM) can in general achieve higher embedding capacity than Spread Spectrum (SS) systems at the same level of distortion. However, QIM is more sensitive to simple attacks such as Additive White Gaussian Noise (AWGN), Uniform Distribution Noise (UDN), and JPEG compression. This paper proposed a system to decompose the host signal into the embedding signal that is designed to be resilient to attacks and the correction signal. QIM is applied on the embedding signal …
Three-Dimensional Profilometry Based On Shift Estimation Of Projected Fringe Patterns, Jose F. Chicharo, Jiangtao Xi, Yingsong Hu, Zongkai Yang, Enbang Li
Three-Dimensional Profilometry Based On Shift Estimation Of Projected Fringe Patterns, Jose F. Chicharo, Jiangtao Xi, Yingsong Hu, Zongkai Yang, Enbang Li
Professor Joe F. Chicharo
This paper presents a new approach to fringe pattern profilometry. In this paper, a generalized model for describing the relationship between the projected fringe pattern and deformed fringe pattern is derived, where the projected fringe pattern can be arbitrary rather than being limited to be sinusoidal as those for the conventional approaches. Based on this model, a new approach is proposed to reconstruct the three-dimensional object surface by estimating the shift between the projected and deformed fringe patterns. Additionally, theoretical analysis and computer simulation results are presented, both of which show the proposed approach can significantly improve the measurement accuracy, …
Blind Source Separation Based On Time-Domain Optimization Of A Frequency-Domain Independence Criterion, Tiemin Mei, Jiangtao Xi, Fuliang Yin, A. Mertins, Jose F. Chicharo
Blind Source Separation Based On Time-Domain Optimization Of A Frequency-Domain Independence Criterion, Tiemin Mei, Jiangtao Xi, Fuliang Yin, A. Mertins, Jose F. Chicharo
Professor Joe F. Chicharo
A new technique for the blind separation of convolutive mixtures is proposed in this paper. Inspired by the works of Amari, Sabala , and Rahbar, we firstly start from the application of Kullback-Leibler divergence in frequency domain, and then we integrate Kullback-Leibler divergence over the whole frequency range of interest to yield a new objective function which turns out to be time-domain variable dependent. In other words, the objective function is derived in frequency domain which can be optimized with respect to time domain variables. The proposed technique has the advantages of frequency domain approaches and is suitable for very …
Cellular Neural Network Based Deformation Simulation With Haptic Force Feedback, Yongmin Zhong, Bijan Shirinzadeh, Gursel Alici, Julian Smith
Cellular Neural Network Based Deformation Simulation With Haptic Force Feedback, Yongmin Zhong, Bijan Shirinzadeh, Gursel Alici, Julian Smith
Gursel Alici
This paper presents a new methodology for deformable object modelling by drawing an analogy between cellular neural network (CNN) and elastic deformation. The potential energy stored in an elastic body as a result of a deformation caused by an external force is propagated among mass points by the non-linear CNN activity. An improved CNN model is developed for propagating the energy generated by the external force on the object surface in the natural manner of Poisson equation. The proposed methodology models non-linear materials with nonlinear CNN rather than geometric non-linearity in the most existing deformation methods. It can not only …
A Bio-Inspired Robotic Locomotion System Based On Conducting Polymer Actuators, Gursel Alici, Daniel Gunderson
A Bio-Inspired Robotic Locomotion System Based On Conducting Polymer Actuators, Gursel Alici, Daniel Gunderson
Gursel Alici
This paper presents the conceptual design and testing of a bio-inspired locomotion system activated through ionic-type conducting polymer actuators, which can operate both in dry and wet environments. The locomotion system is proposed for a mini autonomous crawling device for applications typified by pipe inspection, search, inspection and data gathering in confined spaces, which require mini-robotic systems. The locomotion system is based on the cilia, which has a simple planar bending motion. This type of motion can be provided by bending-type polymer actuators (one-end fixed and the other-end free cantilever beam). The actuators mounted on a printed circuit board and …
Motion Tracking Control Of Piezo-Driven Flexure-Based Mechanism Based On Sliding Mode Strategy, Hwee Choo Liaw, Bijan Shirinzadeh, Julian Smith, Gursel Alici
Motion Tracking Control Of Piezo-Driven Flexure-Based Mechanism Based On Sliding Mode Strategy, Hwee Choo Liaw, Bijan Shirinzadeh, Julian Smith, Gursel Alici
Gursel Alici
This paper presents a motion tracking control methodology based on sliding mode strategy for a flexure-based micro/nano manipulator driven by a piezoelectric actuator. This control methodology is proposed for tracking of desired motion trajectories in the presence of uncertain system parameters, non-linearities including the hysteresis effect, and external disturbances in the control system. In this paper, a four-bar link is investigated and a lumped parameter dynamic model is established for the formulation of the proposed sliding mode motion control methodology. The convergence of the position tracking error to zero is assured by the approach in the presence of the aforementioned …
Model-Based Adaptive Control Of Piezoelectric Actuation Systems, Hwee Choo Liaw, Denny Oetomo, Bijan Shirinzadeh, Gursel Alici
Model-Based Adaptive Control Of Piezoelectric Actuation Systems, Hwee Choo Liaw, Denny Oetomo, Bijan Shirinzadeh, Gursel Alici
Gursel Alici
This paper proposes a model-based adaptive control methodology for piezoelectric actuation systems to follow specified motion trajectories. This is motivated by a search for an effective control strategy to deal with the problem of parametric uncertainties such as disturbance and hysteresis effects. The proposed adaptive law is formulated by combining a parameter compensator and a conventional PD feedback control for a system to drive its position tracking error converging to zero. The fundamental concept lies in the properties of a quasinatural potential function, which allows a saturated position error function in the control formulation. Implementation of the control law requires …
Contact State Determination For Robotic-Based Cylindrical Pair Height Adjustment Under Dynamic Conditions, Prasan I. De Waas Tilakaratna, Bijan Shirinzadeh, Gursel Alici
Contact State Determination For Robotic-Based Cylindrical Pair Height Adjustment Under Dynamic Conditions, Prasan I. De Waas Tilakaratna, Bijan Shirinzadeh, Gursel Alici
Gursel Alici
This paper investigates fine motion strategies associated with the height adjustment manipulations of a cylindrical pair which can be utilised in dynamic assembly and reconfigurable workholding systems. The outer link of the cylindrical pair is held by the end-effector of a 6DOF serial articulated robot. The environment which holds the inner link can be dynamic. Formulations capable of identifying the type of contact between the links and parameters vital for control purposes based on the force and torque data provided by a wrist mounted F/T sensor are established for a generic spatial case. Experimental results indicate that the established methodology …
A Continuously-Stable Linear Actuation Based On Bending Type Artificial Muscles, Rahim Mutlu, Gursel Alici
A Continuously-Stable Linear Actuation Based On Bending Type Artificial Muscles, Rahim Mutlu, Gursel Alici
Gursel Alici
Electroactive polymer actuators, also known as artificial muscles, can operate both in wet and dry media under as small as 1 Volt potential difference. This paper reports on a multi-stable linear actuation mechanism articulated with artificial muscles. Kinematic and finite element analyses of the mechanism are studied to demonstrate the feasibility of the mechanism. Experiments were conducted on a real mechanism articulated with a multiple number (4 or 8) of electroactive polymer actuators, which had the dimensions of 12×2×0.17mm. The numerical and experimental results demonstrate that the angular displacement of the artificial muscles is accurately transformed into a rectilinear motion …
A New Qim-Based Image Watermarking Method And System, Wenming Lu, Wanqing Li, Reihaneh Safavi-Naini, Philip O. Ogunbona
A New Qim-Based Image Watermarking Method And System, Wenming Lu, Wanqing Li, Reihaneh Safavi-Naini, Philip O. Ogunbona
Professor Philip Ogunbona
Embedding capacity, distortion and resilience to attacks are three key indicators to the performance of any image watermarking systems. Study has shown that Quantization Index Modulation (QIM) can in general achieve higher embedding capacity than Spread Spectrum (SS) systems at the same level of distortion. However, QIM is more sensitive to simple attacks such as Additive White Gaussian Noise (AWGN), Uniform Distribution Noise (UDN), and JPEG compression. This paper proposed a system to decompose the host signal into the embedding signal that is designed to be resilient to attacks and the correction signal. QIM is applied on the embedding signal …
Microdroplet-Based Universal Logic Gates By Electrorheological Fluid, Mengying Zhang, Limu Wang, Xiang Wang, Jinbo Wu, Jiaxing Li, Xiuqing Gong, Jianhua Qin, Weihua Li, Weijia Wen
Microdroplet-Based Universal Logic Gates By Electrorheological Fluid, Mengying Zhang, Limu Wang, Xiang Wang, Jinbo Wu, Jiaxing Li, Xiuqing Gong, Jianhua Qin, Weihua Li, Weijia Wen
Professor Weihua Li
We demonstrate a uniquely designed microfluid logic gate with universal functionality, which is capable of conducting all 16 logic operations in one chip, with different input voltage combinations. A kind of smart colloid, giant electrorheological (GER) fluid, functions as the translation media among fluidic, electronic and mechanic information, providing us with the capability of performing large integrations either on-chip or off-chip, while the on-chip hybrid circuit is formed by the interconnection of the electric components and fluidic channels, where the individual microdroplets travelling in a channel represents a bit. The universal logic gate reveals the possibilities of achieving a large-scale …
Microdroplet-Based Universal Logic Gates By Electrorheological Fluid, Mengying Zhang, Limu Wang, Xiang Wang, Jinbo Wu, Jiaxing Li, Xiuqing Gong, Jianhua Qin, Weihua Li, Weijia Wen
Microdroplet-Based Universal Logic Gates By Electrorheological Fluid, Mengying Zhang, Limu Wang, Xiang Wang, Jinbo Wu, Jiaxing Li, Xiuqing Gong, Jianhua Qin, Weihua Li, Weijia Wen
Professor Weihua Li
We demonstrate a uniquely designed microfluid logic gate with universal functionality, which is capable of conducting all 16 logic operations in one chip, with different input voltage combinations. A kind of smart colloid, giant electrorheological (GER) fluid, functions as the translation media among fluidic, electronic and mechanic information, providing us with the capability of performing large integrations either on-chip or off-chip, while the on-chip hybrid circuit is formed by the interconnection of the electric components and fluidic channels, where the individual microdroplets travelling in a channel represents a bit. The universal logic gate reveals the possibilities of achieving a large-scale …
Characterization Of Conducting-Polymer-Based Bimorph Vibration Sensors, Weihua Li, Geoffrey M. Spinks, Lianbin Zhao, Yanzhe Wu, Dezhi Zhou, G G. Wallace
Characterization Of Conducting-Polymer-Based Bimorph Vibration Sensors, Weihua Li, Geoffrey M. Spinks, Lianbin Zhao, Yanzhe Wu, Dezhi Zhou, G G. Wallace
Professor Weihua Li
This paper presents theoretical and experimental investigation of mechanical-electrical properties of conducting polymers based bimorph sensors. A material parameter, hCP , is proposed to represent linear relationship between induction charge and the applied external deformation. Based on this assumption, a constitutive equation for bimorph sensors under steady-state external loadings are constructed and then solved. Mechanical-electrical properties of bimorph sensors are experimentally studied using both vibration-amplitude sweep mode and frequency sweep mode. The material parameter hCP , is identified by comparing theoretical analysis and experimental results. The applications of conducting polymers based bimorph sensors in smart structures are also discussed.