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Robotics, IEEE Transactions on

Issue 5 • Date Oct. 2005

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  • Table of contents

    Publication Year: 2005 , Page(s): c1
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  • IEEE Transactions on Robotics publication information

    Publication Year: 2005 , Page(s): c2
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  • Dynamic characteristics of a novel self-drive pipeline pig

    Publication Year: 2005 , Page(s): 781 - 789
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB) |  | HTML iconHTML  

    This paper presents a dynamic model for a novel self-drive pipeline robot or "pig," which obtains its power from the kinetic energy of fluid flow in a pipe via a turbine and a reverse-traverse screw mechanism. The new robot is designed to move both against and with the flowing fluid, which makes it different from conventional "pigs", which can only move with the flowing fluid. This bidirectional capability makes it very valuable to many industries, especially the oil and gas industries. Based on the model, the dynamic behavior of the new robot under different conditions has been analyzed in detail. In order to verify the validity of the dynamic model, a prototype machine and pipe-loop test rig was built, and experimental data obtained compared well with the theoretical analyses. Both the theoretical and experimental results validated the practicability of this novel robot structure. Furthermore, detailed analysis has been carried out, and the conclusions that have been drawn provide basic design principles for this new pipeline robot, and will assist in the aim of optimizing details of its design. View full abstract»

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  • Application of a multi-DOF ultrasonic servomotor in an auditory tele-existence robot

    Publication Year: 2005 , Page(s): 790 - 800
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1232 KB) |  | HTML iconHTML  

    A multi-degree-of-freedom (DOF) ultrasonic motor can rotate in three DOFs and does not generate noise. In addition, with an appropriate preloading mechanism, it can generate high torque for its size. The multi-DOF ultrasonic motor is, therefore, anticipated for use as a servomotor in the next generation of robots. However, for several reasons, there have been few applications of multi-DOF ultrasonic motors. One reason is the difficulty in designing a proper preloading mechanism for the motor and the limitation of the size of the stators. Another is the difficulty in developing a control algorithm, due to the motor's complex and changing dynamical characteristics, and the serious jaggy motion caused by its very quick response. This paper proposes a preloading mechanism and control algorithm for a multi-DOF ultrasonic motor, considering the motor's application to an actual auditory tele-existence robot, TeleHead. TeleHead is an elaborate dummy head robot that has a 3-DOF neck mechanism. The proposed methods achieve smooth and fast multi-DOF rotating motion of the dummy head with little time delay. In the preloading method, tensioned springs generate high preloading force and make up for the lack of torque by compensating for the resistance torque generated by the inclining motion of the dummy head. In the control algorithm, high-DOF motion is managed by high-frequency switching of the rotating axis, and smooth and quick trajectory tracking motion is achieved by introducing feed-forward control using an inverse model, with multiresolution acquired by feedback-error learning. Experimental results verify the high performance of these methods. View full abstract»

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  • A fingerprint pointing device utilizing the deformation of the fingertip during the incipient slip

    Publication Year: 2005 , Page(s): 801 - 811
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1888 KB) |  | HTML iconHTML  

    In this paper, a novel pointing device is proposed that utilizes the deformation of the fingertip. When a fingertip is pressed and slightly slid on a rigid plate, a partial slip, called an "incipient slip", occurs on the contact surface. While the deformation around the center of the contact area is small during the incipient slip, the boundary region moves to the sliding direction of the fingertip. The deformation changes depending on the sliding distance of the fingertip and the exerted force on the contact surface. The velocity of the pointer can be determined by the estimated distance and force based on the measurement of the deformation. In this study, the correlation between the sliding distance of the fingertip and the deformation and between the exerted force and the deformation are investigated. The degree of the deformation due to the sliding motion can be estimated based on the detected fingerprint center. The group delay spectrum tracking method is proposed for the detection of the fingerprint center. A prototype pointing device is developed to evaluate the operationality of the proposed device. Comparative experiments with conventional pointing devices are conducted. The validity of the proposed device is confirmed by the experiments. View full abstract»

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  • Generating classes of locally orthogonal Gough-Stewart platforms

    Publication Year: 2005 , Page(s): 812 - 820
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (456 KB) |  | HTML iconHTML  

    This paper develops methods for generating classes of orthogonal Gough-Stewart platforms (OGSPs). First, a new, two-parameter class of six-strut OGSPs which leads to isotropic manipulators are found. Next, this class is extended to include redundant Gough-Stewart platforms (GSPs). For an even number of struts, the same algorithm used to generate the six-strut case can be employed. For an odd number of struts, similar essential concepts are used to derive seven-strut and nine-strut OGSPs. Maximization of fault tolerance is implemented for a nine-strut isotropic OGSP. By exploiting invariant properties of the inverse Jacobian, new methods for favorably altering the center of gravity, strut attachment surface, and strut spatial distribution are developed. View full abstract»

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  • Design of reactionless 3-DOF and 6-DOF parallel manipulators using parallelepiped mechanisms

    Publication Year: 2005 , Page(s): 821 - 833
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1288 KB) |  | HTML iconHTML  

    In this paper, the design of reactionless 3-degree-of-freedom (DOF) and 6-DOF parallel manipulators is presented. At first, the design and dynamic balancing of a novel 3-DOF parallel mechanism referred to as the parallelepiped mechanism are addressed. Two types of actuation schemes of the mechanism are considered, and the two corresponding mechanical structures are designed. The balancing equations are derived by imposing that the center of mass of the mechanism is fixed and that the total angular momentum is constant with respect to a fixed point. Optimization is performed to determine the counterweights and counter-rotations based on the balancing conditions. Numerical examples of reactionless 3-DOF parallelepiped mechanisms are given. The dynamic simulation software ADAMS is used to simulate the motion of the mechanisms and to verify that the mechanisms are reactionless at all times and for arbitrary trajectories. Finally, the 3-DOF parallelepiped mechanisms are used as legs to synthesize reactionless 6-DOF parallel manipulators. View full abstract»

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  • A unified approach for inverse and direct dynamics of constrained multibody systems based on linear projection operator: applications to control and simulation

    Publication Year: 2005 , Page(s): 834 - 849
    Cited by:  Papers (29)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (664 KB) |  | HTML iconHTML  

    This paper presents a unified approach for inverse and direct dynamics of constrained multibody systems that can serve as a basis for analysis, simulation, and control. The main advantage of the dynamics formulation is that it does not require the constraint equations to be linearly independent. Thus, a simulation may proceed even in the presence of redundant constraints or singular configurations, and a controller does not need to change its structure whenever the mechanical system changes its topology or number of degrees of freedom. A motion-control scheme is proposed based on a projected inverse-dynamics scheme which proves to be stable and minimizes the weighted Euclidean norm of the actuation force. The projection-based control scheme is further developed for constrained systems, e.g., parallel manipulators, which have some joints with no actuators (passive joints). This is complemented by the development of constraint force control. A condition on the inertia matrix resulting in a decoupled mechanical system is analytically derived that simplifies the implementation of the force control. Finally, numerical and experimental results obtained from dynamic simulation and control of constrained mechanical systems, based on the proposed inverse and direct dynamics formulations, are documented. View full abstract»

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  • Geometric integration on Euclidean group with application to articulated multibody systems

    Publication Year: 2005 , Page(s): 850 - 863
    Cited by:  Papers (29)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (632 KB) |  | HTML iconHTML  

    Numerical integration methods based on the Lie group theoretic geometrical approach are applied to articulated multibody systems with rigid body displacements, belonging to the special Euclidean group SE(3), as a part of generalized coordinates. Three Lie group integrators, the Crouch-Grossman method, commutator-free method, and Munthe-Kaas method, are formulated for the equations of motion of articulated multibody systems. The proposed methods provide singularity-free integration, unlike the Euler-angle method, while approximated solutions always evolve on the underlying manifold structure, unlike the quaternion method. In implementing the methods, the exact closed-form expression of the differential of the exponential map and its inverse on SE(3) are formulated in order to save computations for its approximation up to finite terms. Numerical simulation results validate and compare the methods by checking energy and momentum conservation at every integrated system state. View full abstract»

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  • Discrete abstractions for robot motion planning and control in polygonal environments

    Publication Year: 2005 , Page(s): 864 - 874
    Cited by:  Papers (66)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (712 KB) |  | HTML iconHTML  

    In this paper, we present a computational framework for automatic generation of provably correct control laws for planar robots in polygonal environments. Using polygon triangulation and discrete abstractions, we map continuous motion planning and control problems, specified in terms of triangles, to computationally inexpensive problems on finite-state-transition systems. In this framework, discrete planning algorithms in complex environments can be seamlessly linked to automatic generation of feedback control laws for robots with underactuation constraints and control bounds. We focus on fully actuated kinematic robots with velocity bounds and (underactuated) unicycles with forward and turning speed bounds. View full abstract»

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  • Randomized pursuit-evasion in a polygonal environment

    Publication Year: 2005 , Page(s): 875 - 884
    Cited by:  Papers (46)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB) |  | HTML iconHTML  

    This paper contains two main results. First, we revisit the well-known visibility-based pursuit-evasion problem, and show that in contrast to deterministic strategies, a single pursuer can locate an unpredictable evader in any simply connected polygonal environment, using a randomized strategy. The evader can be arbitrarily faster than the pursuer, and it may know the position of the pursuer at all times, but it does not have prior knowledge of the random decisions made by the pursuer. Second, using the randomized algorithm, together with the solution to a problem called the "lion and man problem" as subroutines, we present a strategy for two pursuers (one of which is at least as fast as the evader) to quickly capture an evader in a simply connected polygonal environment. We show how this strategy can be extended to obtain a strategy for a polygonal room with a door, two pursuers who have only line-of-sight communication, and a single pursuer (at the expense of increased capture time). View full abstract»

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  • Roadmap-based motion planning in dynamic environments

    Publication Year: 2005 , Page(s): 885 - 897
    Cited by:  Papers (43)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1456 KB) |  | HTML iconHTML  

    In this paper, a new method is presented for motion planning in dynamic environments, that is, finding a trajectory for a robot in a scene consisting of both static and dynamic, moving obstacles. We propose a practical algorithm based on a roadmap that is created for the static part of the scene. On this roadmap, an approximately time-optimal trajectory from a start to a goal configuration is computed, such that the robot does not collide with any moving obstacle. The trajectory is found by performing a two-level search for a shortest path. On the local level, trajectories on single edges of the roadmap are found using a depth-first search on an implicit grid in state-time space. On the global level, these local trajectories are coordinated using an A*-search to find a global trajectory to the goal configuration. The approach is applicable to any robot type in configuration spaces with any dimension, and the motions of the dynamic obstacles are unconstrained, as long as they are known beforehand. The approach has been implemented for both free-flying and articulated robots in three-dimensional workspaces, and it has been applied to multirobot motion planning, as well. Experiments show that the method achieves interactive performance in complex environments. View full abstract»

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  • Motion planning for multitarget surveillance with mobile sensor agents

    Publication Year: 2005 , Page(s): 898 - 908
    Cited by:  Papers (39)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (824 KB) |  | HTML iconHTML  

    In the surveillance of multiple targets by mobile sensor agents (MSAs), system performance relies greatly on the motion-control strategy of the MSAs. This paper investigates the motion-planning problem for a limited resource of M MSAs in an environment of N targets (M View full abstract»

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  • Using PCA in time-of-flight vectors for reflector recognition and 3-D localization

    Publication Year: 2005 , Page(s): 909 - 924
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3784 KB) |  | HTML iconHTML  

    This paper presents a reflector recognition and localization technique in three-dimensional (3-D) environments, using only times-of-flight (TOFs) data obtained from ultrasonic transducers. The recognition and localization technique is based on the principal component analysis applied to the TOF vectors originating from a sensor that contains two emitting transducers and several receivers. The two emitters simultaneously transmit two coded pulses that are detected later on and discriminated by the receivers, after being reflected in the environment. The proposed technique allows for the possibility of not only recognizing the reflectors, but also estimating approximately its localization referred to the sensor. This technique has been tested with three types of reflectors in 3-D environments: planes, edges, and corners. The achieved results are very satisfactory for reflectors located in the range 50-350 cm. View full abstract»

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  • Contact impedance estimation for robotic systems

    Publication Year: 2005 , Page(s): 925 - 935
    Cited by:  Papers (79)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1288 KB) |  | HTML iconHTML  

    In this paper, the problem of online estimation of the mechanical impedance during the contact of a robotic system with an unknown environment is considered. This problem is of great interest when controlling a robot in an unstructured and unknown environment, such as in telemanipulation tasks, since it can be easily shown that the exploitation of the knowledge of the mechanical properties of the environment can greatly improve the performance of the robotic system. In particular, a single-point contact is considered, and the (nonlinear) Hunt-Crossley model is taken into account, instead of the classical (linear) Kelvin-Voigt model. Indeed, the former achieves a better physical consistency and also allows describing the behavior of soft materials. Finally, the online estimation algorithm is described and experimental results are presented and discussed. View full abstract»

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  • Passive bilateral control and tool dynamics rendering for nonlinear mechanical teleoperators

    Publication Year: 2005 , Page(s): 936 - 951
    Cited by:  Papers (31)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1136 KB) |  | HTML iconHTML  

    We propose a passive bilateral teleoperation control law for a pair of n-degree-of-freedom (DOF) nonlinear robotic systems. The control law ensures energetic passivity of the closed-loop teleoperator with power scaling, coordinates motions of the master and slave robots, and installs useful task-specific dynamics for inertia scaling, motion guidance, and obstacle avoidance. Consequently, the closed-loop teleoperator behaves like a common passive mechanical tool. A key innovation is the passive decomposition, which decomposes the 2n-DOF nonlinear teleoperator dynamics into two robot-like systems without violating passivity: an n-DOF shape system representing the master-slave position coordination aspect, and an n-DOF locked system representing the dynamics of the coordinated teleoperator. The master-slave position coordination is then achieved by regulating the shape system, while programmable apparent inertia of the coordinated teleoperator is achieved by scaling the inertia of the locked system. To achieve this perfect coordination and inertia scaling, the proposed control law measures and compensates for environment and human forcing. Passive velocity field control and artificial potential field control are used to implement guidance and obstacle avoidance for the coordinated teleoperator. The designed control is also implemented in an intrinsically passive negative semidefinite structure to ensure energetic passivity of the closed-loop teleoperator, even in the presence of parametric model uncertainties and inaccurate force sensing. Experiments are performed to validate the properties of the proposed control framework. View full abstract»

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  • Effects of position quantization and sampling rate on virtual-wall passivity

    Publication Year: 2005 , Page(s): 952 - 964
    Cited by:  Papers (53)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (832 KB) |  | HTML iconHTML  

    The "virtual wall" is the most common building block used in constructing haptic virtual environments. A virtual wall is typically based on a simple spring model, with unilateral constraints that allow the user to make and break contact with a surface. There are a number of factors (sample-and-hold, device dynamics, sensor quantization, etc.) that cause virtual walls to demonstrate active (nonpassive) behavior, destroying the illusion of reality. In this paper, we find an explicit upper bound on virtual wall stiffness that is a necessary and sufficient condition for virtual wall passivity. We consider a haptic display that can be modeled as a mass with Coulomb-plus-viscous friction, being acted upon by two external forces: an actuator and a human user. The system is equipped with only one sensor, an optical encoder measuring the position of the mass. We explicitly model the effects of position resolution, which has not been done in previous work. We make no assumptions about the human user, and we consider arbitrary constant sampling rates. The main result of our analysis is a necessary and sufficient condition for passivity that relies on the Coulomb friction in the haptic device, as well as the encoder resolution. We experimentally verify our results with a one-degree-of-freedom haptic display, and find that the system can display nonpassive behavior in two decoupled modes that are predicted by the necessary and sufficient condition. One mode represents instability, while the other mode results in active tactile sensations. View full abstract»

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  • Control of an object with parallel surfaces by a pair of finger robots without object sensing

    Publication Year: 2005 , Page(s): 965 - 976
    Cited by:  Papers (24)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (904 KB) |  | HTML iconHTML  

    This paper proposes a method for controlling an object with parallel surfaces in a horizontal plane by a pair of finger robots. The control method can achieve stable grasping, relative orientation control, and relative position control of the grasped object. The control inputs require neither any object parameters nor any object sensing, such as tactile sensors, force sensors, or visual sensors. The control inputs are also quite simple and do not need to solve either inverse kinematics or inverse dynamics. The stability of the closed-loop system is proved, and simulation and experimental results validate the control method. View full abstract»

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  • Sensory reflex control for humanoid walking

    Publication Year: 2005 , Page(s): 977 - 984
    Cited by:  Papers (56)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1144 KB) |  | HTML iconHTML  

    Since a biped humanoid inherently suffers from instability and always risks tipping itself over, ensuring high stability and reliability of walk is one of the most important goals. This paper proposes a walk control consisting of a feedforward dynamic pattern and a feedback sensory reflex. The dynamic pattern is a rhythmic and periodic motion, which satisfies the constraints of dynamic stability and ground conditions, and is generated assuming that the models of the humanoid and the environment are known. The sensory reflex is a simple, but rapid motion programmed in respect to sensory information. The sensory reflex we propose in this paper consists of the zero moment point reflex, the landing-phase reflex, and the body-posture reflex. With the dynamic pattern and the sensory reflex, it is possible for the humanoid to walk rhythmically and to adapt itself to the environmental uncertainties. The effectiveness of our proposed method was confirmed by dynamic simulation and walk experiments on an actual 26-degree-of-freedom humanoid. View full abstract»

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  • An ultraprecision six-axis visual servo-control system

    Publication Year: 2005 , Page(s): 985 - 993
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1008 KB) |  | HTML iconHTML  

    This paper presents the development of a novel active visual measurement technique, laterally sampled white-light interferometry (L-SWLI), which is capable of real-time visual tracking of six-degree-of-freedom (6-DOF) rigid body motion with near-nanometer precision. The visual tracking system is integrated with a 6-DOF motion stage to realize an ultraprecision six-axis visual servo-control system. Contrary to conventional interferometric techniques, L-SWLI obtains the complete pose of the target object from a single image frame, therefore allowing real-time tracking. Six-DOF motions are obtained from measuring the fringe pattern on multiple surfaces of the object or from a single surface with additional information gained from conventional image-processing techniques. The feasibility of the visually servoed motion scheme was demonstrated on a micro cantilever. The cantilever was maneuvered in a three-dimensional space with near-nanometer motion resolution in all three translational axes. View full abstract»

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  • A calibration method for odometry of mobile robots based on the least-squares technique: theory and experimental validation

    Publication Year: 2005 , Page(s): 994 - 1004
    Cited by:  Papers (33)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1056 KB) |  | HTML iconHTML  

    For a mobile robot, odometry calibration consists of the identification of a set of kinematic parameters that allow reconstructing the vehicle's absolute position and orientation starting from the wheels' encoder measurements. This paper develops a systematic method for odometry calibration of differential-drive mobile robots. As a first step, the kinematic equations are written so as to underline linearity in a suitable set of unknown parameters; thus, the least-squares method can be applied to estimate them. A major advantage of the adopted formulation is that it provides a quantitative measure of the optimality of a test motion; this can be exploited to drive guidelines on the choice of the test trajectories and to evaluate accuracy of a solution. The proposed technique has been experimentally validated on two different mobile robots and, in one case, compared with other existing approaches; the obtained results confirm the effectiveness of the proposed calibration method. View full abstract»

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  • Multiview camera-calibration framework for nonparametric distortions removal

    Publication Year: 2005 , Page(s): 1004 - 1009
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (384 KB) |  | HTML iconHTML  

    This paper proposes a technique that uses a planar calibration object and projective constraints to calibrate parametric and nonparametric distortions. An iterative surface fitting is first used to constrain a B-spline distortion model by fusing the corrective distortion maps obtained from multiple views. The model is then refined within the whole camera-calibration process. View full abstract»

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  • Feedback-stabilized minimum distance maintenance for convex parametric surfaces

    Publication Year: 2005 , Page(s): 1009 - 1016
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (776 KB) |  | HTML iconHTML  

    A new minimum-distance tracking algorithm is presented for moving convex bodies represented using tiled-together parametric surface patches. The algorithm is formulated by differentiating the geometric minimization problem with respect to time. This produces a hybrid dynamical system that incorporates dependence on rigid body motion, surface shape, and surface boundary interconnectedness. The minimum distance between a pair of previously identified closest features is found by feedback stabilizing the dynamical equations and numerically solving the resulting closed-loop system equations. Maintenance of the minimum distance and the associated closest points during motion is achieved through the action of a feedforward controller and a switching algorithm. The feedforward controller simultaneously accounts for surface shape and motion while the switching controller triggers updates to the extremal feature pair when extremal points on one body cross between Voronoi regions of the other body. In contrast to previously available minimum distance determination algorithms, attractive properties of the new algorithm include a means of determining the highest gain K that maintains stability under a given discretization scheme and a large and easily characterized basin of attraction of the stabilized closest points. These properties may be used to achieve higher computational efficiency. Simulation results are presented for various planar and spatial systems composed of a body and point or composed of two bodies. View full abstract»

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  • A closed-form expression for the uncertainty in odometry position estimate of an autonomous vehicle

    Publication Year: 2005 , Page(s): 1017 - 1022
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (240 KB) |  | HTML iconHTML  

    Using internal and external sensors to provide position estimates in a two-dimensional space is necessary to solve the localization and navigation problems for a robot or an autonomous vehicle (AV). Usually, a unique source of position information is not enough, so researchers try to fuse data from different sensors using several methods, as, for example, Kalman filtering. Those methods need an estimation of the uncertainty in the position estimates obtained from the sensory system. This uncertainty is expressed by a covariance matrix, which is usually obtained from experimental data, assuming, by the nature of this matrix, general and unconstrained motion. We propose in this paper a closed-form expression for the uncertainty in the odometry position estimate of a mobile vehicle, using a covariance matrix whose form is derived from the cinematic model. We then particularize for a nonholonomic Ackerman driving-type AV. Its cinematic model relates the two measures being obtained for internal sensors: the velocity, translated into the instantaneous displacement; and the instantaneous steering angle. The proposed method is validated experimentally, and compared against Kalman filtering. View full abstract»

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  • A stabilizing receding horizon regulator for nonholonomic mobile robots

    Publication Year: 2005 , Page(s): 1022 - 1028
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (296 KB) |  | HTML iconHTML  

    This paper presents a receding horizon (RH) controller used for regulating a nonholonomic mobile robot. The RH control stability is guaranteed by adding a terminal-state penalty to the cost function and a terminal-state region to optimization constraints. A suboptimal solution to the optimization problem is sufficient to achieve stability. A new terminal-state penalty and its corresponding terminal-state constraints are found. Implementation and simulation results are provided to verify the proposed control strategy. View full abstract»

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Aims & Scope

IEEE Transactions on Robotics covers both theory and applications on topics including: kinematics, dynamics, control, and simulation of robots and intelligent machines and systems.

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Meet Our Editors

Editor-in-Chief
Frank Park
Seoul National University