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ARS Journal - Abstracts.

  • Volume 5 Number 1 March 2008

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  • Human-Robot Collaboration: A Literature Review and Augmented Reality Approach in Design, Page 01-18
    Scott A. Green; Mark Billinghurst; XiaoQi Chen and J. Geoffrey Chase

    Abstract: NASA's vision for space exploration stresses the cultivation of human-robotic systems. Similar systems are also envisaged for a variety of hazardous earthbound applications such as urban search and rescue. Recent research has pointed out that to reduce human workload, costs, fatigue driven error and risk, intelligent robotic systems will need to be a significant part of mission design. However, little attention has been paid to joint human-robot teams. Making human-robot collaboration natural and efficient is crucial. In particular, grounding, situational awareness, a common frame of reference and spatial referencing are vital in effective communication and collaboration. Augmented Reality (AR), the overlaying of computer graphics onto the real worldview, can provide the necessary means for a human-robotic system to fulfill these requirements for effective collaboration. This article reviews the field of human-robot interaction and augmented reality, investigates the potential avenues for creating natural human-robot collaboration through spatial dialogue utilizing AR and proposes a holistic architectural design for human-robot collaboration.
    Keywords: augmented reality, collaboration, communication, human-computer interaction, human-robot collaboration, human-robot interaction, robotics.

    On Pose Estimation for Human-Robot Symbiosis, Page 19-30
    Md. Al-Amin Bhuiyan; Chang Hong Liu and Haruki Ueno

    Abstract: This paper presents a vision based pose estimation system using knowledge based approach for human-robot symbiosis. The system is based on visual information of the face by connected component analysis of the skin color segmentation of images in HSV color model and is commenced with the face recognition and pose classification scheme using subspace PCA based pattern-matching strategies. With the knowledge of the known user's profile, face poses are then classified by multilayer perceptron. Based on the frame-based knowledge representation approach, face poses are being interpreted using the Software Platform for Agent and Knowledge (SPAK) management. On face pose recognition, robot is then instructed to perform some specific tasks by issuing pose commands. Experimental results demonstrate that the subspace method is better than that of the standard PCA method for face pose classification. The system has been demonstrated with the implementation of the algorithm to interact with an entertainment robot named, AIBO for human-robot symbiotic relationship.
    Keywords: AIBO, face recognition, human-robot symbiosis, PCA, HSV color model.

    Cooperation of Humanoid Robots using Teleoperation for Transferring an Object, Page 31-40
    Muhammad Usman Keerio; Weimin Zhang and Ali Raza Jafri

    Abstract: In this paper, a method is proposed for humanoid robots performing object transfering task in a teleoperated cooperative paradigm. The cooperative task is accomplished using simple communication among two humanoid robots and then switch between modes according to the situation. In case of object passing with two humanoid robots, mutual position shifts may occur while they are moving. Therefore, it is necessary to correct the position in a real-time manner.To control the arm and hand of the robot remotely we use master arm and hand while it carries and passes the object, the dynamic stability during the execution of walking is ensured by incorporating the ZMP criterion and the desired spacing between the robots is controlled by Leader follower type control .Object passing cooperation for two humanoid robots is based on computer control, wireless LAN, vision, cooperative handling control and text commands. The method is applied as key software of the system. The effectiveness of the proposed methodology for performing cooperatively real time tasks is discussed.
    Keywords: cooperation, teleoperation, real time task.

    Fruit Detachment and Classification Method for Strawberry Harvesting Robot, Page 41-48
    Guo Feng; Cao Qixin and Nagata Masateru

    Abstract: Fruit detachment and on-line classification is important for the development of harvesting robot. With the specific requriements of robot used for harvesting strawberries growing on the ground, a fruit detachment and classification method is introduced in this paper. OHTA color spaces based image segmentation algorithm is utilized to extract strawberry from background; Principal inertia axis of binary strawberry blob is calculated to give the pose information of fruit. Strawberry is picked selectively according to its ripeness and classified according to its shape feature. Histogram matching based method for fruit shape judgment is introduced firstly. Experiment results show that this method can achieve 93% accuracy of strawberry's stem detection, 90% above accuracy of ripeness and shape quality judgment on black and white background. With the improvement of harvesting mechanism design, this method has application potential in the field operation.
    Keywords: machine vision, stem detection, histogram matching, strawberry harvesting robot.

    Ant Intelligence in Robotic Soccer, Page 49-58
    R. Geetha Ramani; P. Viswanath and B. Arjun

    Abstract: Robotic Soccer is a multi-agent test bed, which requires the designer to address most of the issues of multi-agent research. Social insect behaviors observed in nature when adopted to solve problems they are giving promissing results. The domains like computers, electronics, electrical, mechanical etc., are inspired in adopting these behaviors. This paper addresses the ant intelligence in robotic soccer to evolve the best team of players. The simulation team evolved (PUTeam) was tested with teams of soccerbots in teambots (a simulation tool for Robotic Soccer) and the experimental results clearly shows the performance of the evolved team against the opponent teams are more effective.
    Keywords: robotic soccer, social insect behaviors, ant intelligence, learning methods, stigmergy, self-organization.

    Evolving Connectionist System Based Role Allocation for Robotic Soccer, Page 59-62
    L. Huang; Q. Song and N. Kasabov

    Abstract: Robotic soccer is an intelligent system where a group of mobile robots are controlled to perform soccer play (http://www.fira.net). The allocation of a suitable role for each robot in a team is a key for the success of the play. The paper treats this issue as one of pattern classification, and solves it with an Evolving classification function (ECF), a special evolving connectionist system (ECOS). A robot's role is determined by and evolves with the states of system ( robots and target ) in real time. The software and hardware platforms are set up for data collection and learning. The effectiveness of the proposed approach is verified by the experimental studies.
    Keywords: robotic soccer, mobile robots, evolving connectionist systems.

    A Visibility-based Algorithm for Multi-robot Boundary Coverage, Page 63-68
    Linan Jiao and Zhenmin Tang

    Abstract: Cell decomposition is often used in autonomous area coverage. We propose a visibility-based decomposition algorithm for single robot boundary coverage and a corresponding multi-robot algorithm in unknown environment. A graph data structure is exploited for completeness of coverage and incremental description of partially observed world. Visibility-based decomposition facilitates the construction of graph and algorithms operated on it. In the context of multi-robot, a dynamically selected highest priority robot is in charge of information share and synchrony through communication, polygon set operations provide tools for environmental information mergence, a distributed algorithm for multi-robot boundary coverage is proposed based on those technologies. Finally the experimental results show the relationships between robot number and traversable gate number, some future subjects of researches are introduced.
    Keywords: multi-robot, boundary coverage, cell decomposition, visibility, graph.

    Stability on Adaptive NN Formation Control with Variant Formation Patterns and Interaction Topologies, Page 69-82
    Xin Chen and Yangmin Li

    Abstract: The formation task achieved by multiple robots is a tough issue in practice, because of the limitations of the sensing abilities and communicating functions among them. This paper investigates the decentralized formation control in case of parameter uncertainties, bounded disturbances, and variant interactions among robots. To design decentralized controller, a formation description is firstly proposed, which consists of two aspects in terms of formation pattern and interaction topology. Then the formation control using adaptive neural network (ANN) is proposed based on the relative error derived from formation description. From the analysis on stability of the formation control under invariant/variant formation pattern and interaction topology, it is concluded that if formation pattern is of class , , and interaction graph is connected and changed with finite times, the convergence of the formation control is guaranteed, so that robots must form the formation described by the formation pattern.
    Keywords: adapted neural network control, interaction topology, Lyapunov theorem for nonsmooth systems, switched system.

    Robust Control of Wheeled Mobile Manipulators Using Hybird Joints, Page 83-90
    Zhijun Li; Weidong Chen and Hong Liu

    Abstract: In this paper, robust force/motion control strategies are presented for mobile manipulators under both holonomic and nonholonomic constraints in the presence of uncertainties and disturbances. The proposed control strategies guarantee that the system motion converges to the desired manifold with prescribed performance, and constraint force control is developed using the passivity of hybrid joint rather than force feedback control. Experiment results validate that not only the states of the system asymptotically converge to the desired trajectory, but also the constraint force asymptotically converges to the desired force.
    Keywords: wheeled mobile manipulators, motion/force control, hybrid joints.

    Time Optimal Hybrid Sliding Mode-PI Control for an Autonomous Underwater Robot, Page 91-98
    Theerayuth Chatchanayuenyong and Manukid Parnichkun

    Abstract: This paper presents an underwater robot control system using combination principle among sliding mode control (SMC), Pontryagin maximum principle and linear PI control. The SMC switches according to the Pontryagin's time optimal control principle, in which the solution is obtained by using neural network approach to yield a time optimal response at its reaching phase. PI control is used in place of the SMC at the switching phase to avoid high undesired control activity. Performance of the proposed controller is compared with various classical SMCs and conventional linear control systems. Such comparisons ensure the implementation success and prove it as a real time-optimal controller. The results show the controller's good abilities to deal with plant nonlinearity and parameter uncertainties. The controller yields a time optimal control response without high control chattering.
    Keywords: Autonomous Underwater Robot, Time optimal control, Neural network, Hybrid control.

    On Algorithms for Planning S-curve Motion Profiles, Page 99-106
    Kim Doang Nguyen; Teck-Chew Ng and I-Ming Chen

    Abstract: Although numerous researches on s-curve motion profiles have been carried out, up to date, no systematic investigation on the general model of polynomial s-curve motion profiles is considered. In this paper, the model of polynomial s-curve motion profiles is generalized in a recursive form. Based on that, a general algorithm to design s-curve trajectory with time-optimal consideration is proposed. In addition, a special strategy for planning s-curve motion profiles using a trigonometric model is also presented. The algorithms are implemented on a linear motor system. Experimental results show the effectiveness and promising application ability of the algorithms in s-curve motion profiling.
    Keywords: Motion control, s-curve motion profile, trajectory planning algorithm, linear motor.

    Kinematic Design of a Radius-Variable Gripper with 1-D.O.F. used in High-voltage Hot-line Cleaning Robot, Page 107-114
    Yi Gu; Xinhua Weng; Ruqing Yang and Tao Song

    Abstract: This paper presents the design of a novel radius-variable-gripper (RVG) for use as end-effector of high-voltage hot-line cleaning robot (HVCR). A eight-bar linkage mechanism is proposed to obtain the aim of 1-dof acutuation. According to the shape of insulators, the dimension design and kinematic analysis of RVG have been carried out. The optimization is performed to locate the joint points of arm segments, on which the brushes are mounted, approximately on the position circles in the whole opening-and-closing process of RVG. The prototype has been given finally, and it is showed that RVG is feasible to this special application.
    Keywords: Kinematics, optimum design, gripper, hot-line cleaning robot.

    Dynamic Modeling and Inverse Dynamic Analysis of Flexible Parallel Robots, Page 115-122
    Du Zhaocai and Yu Yueqing

    Abstract: This paper presents a method for the dynamic modeling of parallel robots with flexible links and rigid moving platform based on finite element theory. The relation between elastic displacements of links is investigated, taking into consideration the coupling effects of elastic motion and rigid motion. The kinematic and dynamic constraint conditions of elastic displacements of flexible parallel robots are presented. The Kineto-Elastodynamics theory and Timoshenko beam theory are employed to derive the equations of motion, considering the effects of distributed mass, lumped mass, rotary inertia, shearing deformation, bending deformation, lateral deformations and all the dynamic coupling terms. The dynamic behavior due to flexibility of links is well illustrated through numerical simulation. Compared with the results of SAMCEF software simulation, the numerical simulation results show good coherence and the advantages of the method. The flexibility of links is demonstrated to have significant impact on system performance and stability. A method for the inverse dynamic analysis of flexible parallel robots is presented.
    Keywords: flexible parallel robot, flexible link, dynamic modeling, inverse dynamic analysis.

    Mechatronic Model Based Computed Torque Control of a Parallel Manipulator, Page 123-128
    Zhiyong Yang; Jiang Wu; Jiangping Mei; Jian Gao and Tian Huang

    Abstract: With high speed and accuracy the parallel manipulators have wide application in the industry, but there still exist many difficulties in the actual control process because of the time-varying and coupling. Unfortunately, the present-day commercial controlles cannot provide satisfying performance for its single axis linear control only. Therefore, aimed at a novel 2-DOF (Degree of Freedom) parallel manipulator called Diamond 600, a motor-mechanism coupling dynamic model based control scheme employing the computed torque control algorithm are presented in this paper. First, the integrated dynamic coupling model is deduced, according to equivalent torques between the mechanical structure and the PM (Permanent Magnetism) servomotor. Second, computed torque controller is described in detail for the above proposed model. At last, a series of numerical simulations and experiments are carried out to test the effectiveness of the system, and the results verify the favourable tracking ability and robustness.
    Keywords: Parallel manipulator, Motor-mechanism coupling dynamic model, Computed torque control.