Browsing by Author "Chen-Chien Hsu"

Now showing 1 - 20 of 68

2-Dimenional Localization Based on Tilt Photographing of a Single CCD Camera
(2009-02-12) Ming-Yu Cheng; Chen-Chien Hsu; Pei-Jun Lee
This paper provides an image-based localization method based on tilt photographing of a single CCD camera. Image captured by the CCD camera is pre-processing to locate the target object in the picture in terms of pixel count deviation from the CCD camera. By using an established formula based on relationship between tilt angle of the CCD camera and distance, coordinate of the target object can be calculated. Experiment results have demonstrated that the feasibility of the proposed approach with satisfactory accuracy in determining the position of the target object.
Design of an Optimal Fuzzy Controller for Mobile Robots via an Evolutionary Approach
(2009-06-03) Chen-Chien Hsu; June-Wei Huang; Hung-Chih Teng
Design of Infrared Electronic-Toll-Collection Systems with Extended Communication Areas and Performance of Data Transmission
(IEEE Intelligent Transportation Systems Society, 2011-03-01) Wern-Yarng Shieh; Chen-Chien Hsu; Shen-Lung Tung; Po-Wen Lu; Ti-Ho Wang; Shyang-Lih Chang
Based on our previous works in the design of an infrared emitter for electronic-toll-collection (ETC) applications, we use the unidirectional cosinen functions to approximate the irregular radiation pattern for typical infrared low-cost commercial light-emitting diodes (LEDs) with a half-intensity angle Φ1/2 = 10°. With the aid of this approximation, the main characteristics of the performance of an infrared ETC system utilizing this type of LED as the emitter can be investigated based on the received signal strength of the system. For on-off keying, a simple model connecting the received signal strength and the bit error rate (BER) of the system is further established. From the calculated or the measured received signal strength of the system, it is not difficult to estimate the system performance in terms of the BER by this simple model. Roughly speaking, for a typical setting of the circuit parameters and a typical uplink and downlink data-transmission protocol, the data transmission can be very successful in terms of a very low BER if the received signal strength is 1.3 times stronger than the signal strength received at the communication boundary. The emitter presented in this paper is able to produce a relatively extended communication area in the vehicle-traveling direction, resulting in longer communication time interval for the data transmission between the onboard unit (OBU) and the roadside unit (RSU) than conventional emitters. Furthermore, the design presented in this paper is validated by experimental measurement to demonstrate its effectiveness.
Diameter and Depth Measurement of Holes by a Single Camera
(World Scientific and Engineering Academy and Society (WSEAS), 2007-05-01) Chin-Tun Chuang; Ming-Chih Lu; Chen-Chien Hsu; Yin-Yu Lu
Digital redesign of interval systems via particle swarm optimization
(2008-08-15) Chen-Chien Hsu; Chun-Hwui Gao
Digital redesign of uncertain interval systems based on extremal gain/phase margins via a hybrid particle swarm optimizer
(Elsevier, 2010-03-01) Chen-Chien Hsu; Wern-Yarng Shieh; Chun-Hwei Kao
In this paper, a hybrid optimizer incorporating particle swarm optimization (PSO) and an enhanced NM simplex search method is proposed to derive an optimal digital controller for uncertain interval systems based on resemblance of extremal gain/phase margins (GM/PM). By combining the uncertain plant and controller, extremal GM/PM of the redesigned digital system and its continuous counterpart can be obtained as the basis for comparison. The design problem is then formulated as an optimization problem of an aggregated error function in terms of deviation on extremal GM/PM between the redesigned digital system having an interval plant and its continuous counterpart, and subsequently optimized by the proposed optimizer to obtain an optimal set of parameters for the digital controller. Thanks to the performance of the proposed hybrid optimizer, frequency-response performances of the redesigned digital system using the digital controller evolutionarily derived by the proposed approach bare a far better resemblance to its continuous-time counter part in comparison to those obtained using existing open-loop discretization methods.
Digital redesign of uncertain interval systems based on frequency-response resemblance via a hybrid particle swarm optimizer
(2008-07-20) Chen-Chien Hsu; Chun-Hwui Gao
Digital redesign of uncertain interval systems based on time-response resemblance via particle swarm optimization
(2008-06-27) Chen-Chien Hsu; Geng-Yu Lin
In this paper, a novel design approach based on time-response resemblance of the closed-loop system via particle swarm optimization is proposed to improve performance of the redesigned digital system for continuous-time uncertain interval systems. The design rationale of the proposed approach is to derive a digital controller for the redesigned digital system so that step response sequences corresponding to the extremal sequence energy closely match those of their continuous counterpart under the perturbation of the plant parameters. By suitably formulating the design problem as an optimization problem, an evolution framework incorporating three PSOs (particle swarm optimizations) is presented to derive a set of optimal parameters for the digital controller. Computer simulations have shown that time responses of the redesigned digital system having an interval plant have a better resemblance to their continuous-time counter part in comparison those obtained using existing open-loop discretization methods.
Digital redesign of uncertain interval systems based on time-response resemblance via particle swarm optimization
(Elsevier, 2009-07-01) Chen-Chien Hsu; Geng-Yu Lin
In this paper, a particle swarm optimization (PSO) based approach is proposed to derive an optimal digital controller for redesigned digital systems having an interval plant based on time-response resemblance of the closed-loop systems. Because of difficulties in obtaining time-response envelopes for interval systems, the design problem is formulated as an optimization problem of a cost function in terms of aggregated deviation between the step responses corresponding to extremal energies of the redesigned digital system and those of their continuous counterpart. A proposed evolutionary framework incorporating three PSOs is subsequently presented to minimize the cost function to derive an optimal set of parameters for the digital controller, so that step response sequences corresponding to the extremal sequence energy of the redesigned digital system suitably approximate those of their continuous counterpart under the perturbation of the uncertain plant parameters. Computer simulations have shown that redesigned digital systems incorporating the PSO-derived digital controllers have better system performance than those using conventional open-loop discretization methods.
Digital redesign of uncertain interval systems via a hybrid particle swarm optimizer
(Inderscience, 2008-07-01) Chen-Chien Hsu; Chun-Hwei Kao
In this paper, a hybrid optimiser incorporating particle swarm optimisation (PSO) and an enhanced NM simplex search method is proposed to derive an optimal digital controller for uncertain interval systems having an interval plant based on frequency-response resemblance. By combining the uncertain plant and controller, extremal systems for the redesigned digital system and its continuous counterpart can be obtained as the basis for comparison. The design problem is then formulated as an optimisation problem of an aggregated error function in terms of frequency-response deviation between the redesigned digital system and its continuous counterpart, and subsequently optimised by the proposed optimiser to obtain an optimal set of parameters for the digital controller. Thanks to the performance of the proposed hybrid optimiser, frequency envelope of the redesigned digital system using the digital controller evolutionarily derived by the proposed approach bare a better resemblance to its continuous-time counterpart in comparison to those obtained using existing open-loop discretisation methods.
Digital redesign of uncertain interval systems via particle swarm optimization
(World Academy of Science, Engineering and Technology (WASET), 2008-07-01) Chen-Chien Hsu; Chun-Hwui Gao
In this paper, a PSO-based approach is proposed to derive a digital controller for redesigned digital systems having an interval plant based on resemblance of the extremal gain/phase margins. By combining the interval plant and a controller as an interval system, extremal GM/PM associated with the loop transfer function can be obtained. The design problem is then formulated as an optimization problem of an aggregated error function revealing the deviation on the extremal GM/PM between the redesigned digital system and its continuous counterpart, and subsequently optimized by a proposed PSO to obtain an optimal set of parameters for the digital controller. Computer simulations have shown that frequency responses of the redesigned digital system having an interval plant bare a better resemblance to its continuous-time counter part by the incorporation of a PSO-derived digital controller in comparison to those obtained using existing open-loop discretization methods.
Discrete Modelling of Continuous-Time Systems Having Interval Uncertainties Using Genetic Algorithms
(Institute of Electronics, Information and Communication Engineers, 2008-01-01) Chen-Chien Hsu; Tsung-Chi Lu; Heng-Chou Chen
In this paper, an evolutionary approach is proposed to obtain a discrete-time state-space interval model for uncertain continuous-time systems having interval uncertainties. Based on a worst-case analysis, the problem to derive the discrete interval model is first formulated as multiple mono-objective optimization problems for matrix-value functions associated with the discrete system matrices, and subsequently optimized via a proposed genetic algorithm (GA) to obtain the lower and upper bounds of the entries in the system matrices. To show the effectiveness of the proposed approach, roots clustering of the characteristic equation of the obtained discrete interval model is illustrated for comparison with those obtained via existing methods.
Distance and Angle Measurement of Distant Objects on an Oblique Plane Based on Pixel Number Variation of CCD Images
(Institute of Electrical and Electronics Engineers (IEEE), 2011-05-01) Chen-Chien Hsu; Ming-Chih Lu; Yin-Yu Lu
This paper presents an image-based system for measuring target objects on an oblique plane based on pixel number variation of charge-coupled device images for digital cameras by referencing to two arbitrarily designated points in the image frame. Based on an established relationship between the displacement of the camera movement along the photographing direction and the variation in pixel counts between the reference points in the images, photographic distance and incline angle for objects lying on an oblique plane can be calculated via the proposed method. As a real-case application of the proposed approach, 2-D localization of target objects in robot soccer competitions is also demonstrated to show the effectiveness of the proposed approach. To allow the use of widely available digital zoom cameras for ranging and localization by the proposed method, a parameter equivalent to the displacement due to the camera movement is also investigated and derived in this paper.
Distance and Angle Measurement of Distant Objects on an Oblique Plane Based on Pixel Variation of CCD Image
(2010-05-06) Ming-Chih Lu; Chen-Chien Hsu; Yin-Yu Lu
This paper presents an image-based system for measuring target objects on an oblique plane based on pixel variation of CCD images for digital cameras by referencing to two arbitrarily designated points in image frames. Based on an established relationship between the displacement of the camera movement along the photographing direction and the difference in pixel counts between reference points in the images, photographing distance between the camera and an object on the oblique target plane can be calculated via the proposed method.
Distance Measurement Based on Pixel Variation of CCD Images
(2009-02-12) Chen-Chien Hsu; Ming-Chih Lu; Ke-Wei Chin
This paper presents a distance measurement method based on pixel number variation of images for digital cameras by referencing to two arbitrarily designated points in image frames. Based on an established relationship between the displacement of the camera movement along the photographing direction and the difference in pixel counts between reference points in the images, distance from an object can be calculated via the proposed method. To integrate the measuring functions into digital cameras, circuit design implementing the proposed measuring system in selecting reference points, measuring distance, and displaying measurement results on CCD panel of the digital camera is proposed in this paper. In comparison to pattern recognition or image analysis methods, the proposed measuring approach is simple and straightforward for practical implementation into digital cameras. Experiment results have demonstrated that the proposed method is capable of yielding satisfactory measurement results in a very responsive way.
Distance Measurement Based on Pixel Variation of CCD Images
(Elsevier, 2009-10-01) Chen-Chien Hsu; Ming-Chih Lu; Wei-Yen Wang; Yin-Yu Lu
This paper presents a distance measurement method based on pixel number variation of CCD images by referencing to two arbitrarily designated points in the image frames. By establishing a relationship between the displacement of the camera movement along the photographing direction and the difference in pixel count between reference points in the images, the distance from an object can be calculated via the proposed method. To integrate the measuring functions into digital cameras, a circuit design implementing the proposed measuring system in selecting reference points, measuring distance, and displaying measurement results on CCD panel of the digital camera is proposed in this paper. In comparison to pattern recognition or image analysis methods, the proposed measuring approach is simple and straightforward for practical implementation into digital cameras. To validate the performance of the proposed method, measurement results using the proposed method and ultrasonic rangefinders are also presented in this paper.
Distance Measurement Using a Digital Camera
(2006-11-11) Ti-Ho Wang; Ming-Chih Lu; Chen-Chien Hsu; Cheng-Pei Tsai; Cheng-chuan Chen
Dual-Circle Self-Localization Algorithm for Omnidirectional Vision Robots
(Harbin Institute of Technology, 2008-07-01) Chen-Chien Hsu; Ching-Chang Wong; Hung-Chih Teng
This paper proposes a new self-localization algorithm, called dual-circle self-localization algorithm, for use in omnidirectional vision robots. When an autonomous robot navigates in the field, it senses the environment by an omnidirectional vision device fitted on the robot. The landmarks information is acquired by using image processing and pattern recognition techniques. Robot position on the field can be estimated with the proposed method by using these landmarks information. Comparing with other self-localization methods, the dual-circle self-localization algorithm requires only three landmarks information in the image for identifying the robot position, which is very efficient for image processing. Practical experiments on an autonomous robot have demonstrated that the proposed algorithm can achieve a satisfactory performance to locate the robot.
Dual-Circle Self-Localization of Autonomous Soccer Robots with Omnidirectional Vision Robotics and Autonomous Systems
(Taylor & Francis, 2012-06-01) Chen-Chien Hsu; Ching-Chang Wong; Hung-Chih Teng; Cheng-Yao Ho
A self-localization method entitled Dual-Circle Self-Localization (DCSL) for mobile robots in a soccer robot game filed is proposed in this paper. To evaluate the performance of the proposed localization method, an omnidirectional vision device is installed on top of the robot to capture images for recognizing objects in the environment via a hybrid scanning method. Three reliable objects recognized are then chosen as landmarks to calculate the position of the robot in the game field via the proposed DCSL based on relative positions between the robot and landmarks in the omnidirectional images. Because simple geometric manipulations are only required via the DCSL algorithm, localization efficiency can be significantly improved while maintaining a relatively smaller mean error in comparison to Monte Carlo Localization techniques as demonstrated in both simulation results and practical experiments in this paper.
Global Optimization Using Novel Randomly Adapting Particle Swarm Optimization Approach
(2011-10-12) Nai-Jen Li; Wen-June Wang; Chen-Chien Hsu; Chih-Min Lin
This paper proposes a novel randomly adapting particle swarm optimization (RAPSO) approach which uses a weighed particle in a swarm to solve multi-dimensional optimization problems. In the proposed method, the strategy of the RAPSO acquires the benefit from a weighed particle to achieve optimal position in explorative and exploitative search. The weighed particle provides a better direction of search and avoids trapping in local solution during the optimization process. The simulation results show the effectiveness of the RAPSO, which outperforms the traditional PSO method, cooperative random learning particle swarm optimization (CRPSO), genetic algorithm (GA) and differential evolution (DE) on the 6 benchmark functions.