By Topic

Robotics and Automation, IEEE Transactions on

Issue 1 • Date Feb. 2004

Filter Results

Displaying Results 1 - 25 of 28
  • Table of contents

    Page(s): c1
    Save to Project icon | Request Permissions | PDF file iconPDF (34 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Robotics and Automation publication information

    Page(s): c2
    Save to Project icon | Request Permissions | PDF file iconPDF (36 KB)  
    Freely Available from IEEE
  • Self-calibration of a rotating camera with a translational offset

    Page(s): 1 - 14
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (312 KB) |  | HTML iconHTML  

    Camera self calibration, based on a purely rotational movement of the camera, receives the most attention among different camera self-calibration methods due to its algorithmic simplicity. The existing purely rotational methods, however, assume camera rotates around its optical center, therefore yielding no translation offset. This assumption is not realistic, since in practice, the precise location of the optical center is often unknown, and the rotation is often performed about an unknown but fixed point near the optical center. The conventional methods tend to ignore the offset, and therefore, could lead to significant errors with the estimated camera parameters. In this paper, we introduce a new rotation-based camera self-calibration method, which explicitly accounts for the unknown translation offset. To this end, the problem is mathematically formulated and solved for differently taking the translation into consideration. To obtain the camera parameters with unknown camera rotations, our algorithm requires the camera to rotate around an unknown but fixed axis twice, by the same yet unknown angle. This is not an unreasonable assumption for precalibrating a camera on an active head. Experiments with both synthetic and real data show that the systematic errors caused by ignoring the translational offset will be effectively eliminated by our approach. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Uncalibrated Euclidean 3-D reconstruction using an active vision system

    Page(s): 15 - 25
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1312 KB) |  | HTML iconHTML  

    Uncalibrated reconstruction of a scene is desired in many practical applications of computer vision. However, using a single camera with unconstrained motion and unknown parameters, a true Euclidean three-dimensional (3-D) model of the scene cannot be reconstructed. In this paper, we present a method for true Euclidean 3-D reconstruction using an active vision system consisting of a pattern projector and a camera. When the intrinsic and extrinsic parameters of the camera are changed during the reconstruction, they can be self-calibrated and the real 3-D model of the scene can then be reconstructed. The parameters of the projector are precalibrated and are kept constant during the reconstruction process. This allows the configuration of the vision system to be varied during a reconstruction task, which increases its self-adaptability to the environment or scene structure in which it is to work. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Measurement of finger posture and three-axis fingertip touch force using fingernail sensors

    Page(s): 26 - 35
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (880 KB) |  | HTML iconHTML  

    When the human fingertip is pressed against a surface or bent, the hemodynamic state of the fingertip is altered due to mechanical interactions between the fingernail and bone. Normal force, shear force, and finger extension/flexion all result in different patterns of blood volume beneath the fingernail. This phenomenon has been exploited in order to detect finger forces and finger posture by creating a photoplethysmograph "fingernail sensor," which measures the two-dimensional pattern of blood volume beneath the fingernail. In this paper, a filter is designed to predict the normal force, lateral shear force, longitudinal shear force, and bending angle based on readings from the fingernail sensor. Linear, polynomial, and neural network models relating the bending angle and touch forces to optical sensor outputs are developed and tested. A method is developed to uniformly calibrate the predictor for each user. Calibration experiments are performed to train and validate the predictor for seven human subjects. Results show that on average, shear forces can be predicted with 0.5 N root mean square (rms) error, normal force with 1 N rms error, and posture angle with 10 degrees rms error. Applications and methods for improving performance are discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Localization of a mobile robot using relative bearing measurements

    Page(s): 36 - 44
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (392 KB)  

    In this paper, the problem of recursive robot localization based on relative bearing measurements is considered, where unknown but bounded measurement uncertainties are assumed. A common approach is to approximate the resulting set of feasible states by simple-shaped bounding sets such as, e.g., axis-aligned boxes, and calculate the optimal parameters of this approximation based on the measurements and prior knowledge. In the novel approach presented here, a nonlinear transformation of the measurement equation into a higher dimensional space is performed. This yields a tight, possibly complex-shaped, bounding set in a closed-form representation whose parameters can be determined analytically for the measurement step. It is shown that the new bound is superior to commonly used outer bounds. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Nearness diagram (ND) navigation: collision avoidance in troublesome scenarios

    Page(s): 45 - 59
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1960 KB) |  | HTML iconHTML  

    This paper addresses the reactive collision avoidance for vehicles that move in very dense, cluttered, and complex scenarios. First, we describe the design of a reactive navigation method that uses a "divide and conquer" strategy based on situations to simplify the difficulty of the navigation. Many techniques could be used to implement this design (since it is described at symbolic level), leading to new reactive methods that must be able to navigate in arduous environments (as the difficulty of the navigation is simplified). We also propose a geometry-based implementation of our design called the nearness diagram navigation. The advantage of this reactive method is to successfully move robots in troublesome scenarios, where other methods present a high degree of difficulty in navigating. We show experimental results on a real vehicle to validate this research, and a discussion about the advantages and limitations of this new approach. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A motion-planning approach to folding: from paper craft to protein folding

    Page(s): 60 - 71
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (496 KB) |  | HTML iconHTML  

    In this paper, we present a framework for studying folding problems from a motion-planning perspective. The version of the motion-planning problem we consider is that of determining a sequence of motions to transform some configuration of a foldable object (the start) into another configuration (the goal). Modeling foldable objects as tree-like multilink objects allows us to apply motion-planning techniques for articulated objects with many degrees of freedom (many links) to folding problems. An important feature of this approach is that it not only allows us to study foldability questions, such as, can one object be folded (or unfolded) into another object, but it also provides us with another tool for investigating the dynamic folding process itself. The framework proposed here has application to traditional motion-planning areas such as automation and animation, to paper-folding problems studied in computational geometry, and to computational biology problems such as protein folding. Preliminary experimental results with paper folding and the folding of small proteins (approximately 60 residues) are quite encouraging. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Visual servoing invariant to changes in camera-intrinsic parameters

    Page(s): 72 - 81
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB) |  | HTML iconHTML  

    This paper presents a new visual servoing scheme which is invariant to changes in camera-intrinsic parameters. Current visual servoing techniques are based on the learning of a reference image with the same camera used during the servoing. With the new method, it is possible to position a camera (with eventually varying intrinsic parameters), with respect to a nonplanar object, given a "reference image" taken with a completely different camera. The necessary and sufficient conditions for the local asymptotic stability show that the control law is robust in the presence of large calibration errors. Local stability implies that the system can accurately track a path in the invariant space. The path can be chosen such that the camera follows a straight line in the Cartesian space. Simple sufficient conditions are given in order to keep the tracking error bounded. This promising approach has been successfully tested with an eye-in-hand robotic system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Modeling and control of contact between constrained rigid bodies

    Page(s): 82 - 92
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (264 KB) |  | HTML iconHTML  

    This paper examines the phenomenon of frictionless contact between rigid bodies that are already subject to kinematic constraints from some other source. Such contacts occur frequently when robots interact with their environments, in which case, the additional constraints come from the robot mechanisms. A proper analysis of these contacts must consider both sets of constraints. This paper presents a general model of constrained-body contact, expressed in invariant terms; a method of resolving equations of motion into decoupled subsystems with respect to the contact's motion and force freedoms; an equation of motion for possibly redundant robots experiencing constrained-body contact, which employs a novel decomposition of the robot's joint space into dynamically decoupled subspaces; and a dynamically decoupled hybrid motion/force-control system based on the same decomposition. It is shown that disturbances from an unknown dynamic environment are automatically confined to the force-control subsystem, and that a modification to the control law can factor these disturbances out of the controlled response. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Attitude control for a micromechanical flying insect via sensor output feedback

    Page(s): 93 - 106
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1864 KB) |  | HTML iconHTML  

    In this paper, we study attitude stabilization strategies via output sensor feedback for micro aerial vehicles (MAVs), inch-size robots capable of autonomous flight. In order to compensate for the size and power limitations of MAVs, we introduce the ocelli and halteres, the body orientation and rotation sensing mechanisms used by flying insects. The analysis and simulations of these sensors show the feasibility of using such biologically inspired approaches to build biomimetic gyroscopes and angular position detectors. Finally, attitude stabilization techniques based on these sensors are proposed and successfully tested on an aerodynamic model for a micromechanical flying insect (NIFI). To the authors' knowledge, this is the first attempt in using output feedback from biomimetic devices with ocelli and halteres to achieve attitude stabilization in MAVs. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Data-mining approach to production control in the computer-integrated testing cell

    Page(s): 107 - 116
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (328 KB) |  | HTML iconHTML  

    This paper presents a data-mining-based production control approach for the testing and rework cell in a dynamic computer-integrated manufacturing system. The proposed competitive decision selector (CDS) observes the status of the system and jobs at every decision point, and makes its decision on job preemption and dispatching rules in real time. The CDS equipped with two algorithms combines two different knowledge sources, the long-run performance and the short-term performance of each rule on the various status of the system. The short-term performance information is mined by a data-mining approach from large-scale training data generated by simulation with data partition. A decision tree-based module generates classification rules on each partitioned data that are suitable for interpretation and verification by users and stores the rules in the CDS knowledge bases. Experimental results show that the CDS dynamic control is better than other common control rules with respect to the number of tardy jobs. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Structure synthesis of a class of 3-DOF rotational parallel manipulators

    Page(s): 117 - 121
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (360 KB)  

    The theory of reciprocal screws is used for the enumeration of the feasible limb structures of a class of 3-degree-of-freedom (DOF) rotational parallel manipulators. Geometric conditions for the moving platform to possess finite spherical motion are described. A table of feasible limbs that can be used for the construction of 3-DOF rotational parallel manipulators is developed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A simple and analytical procedure for calibrating extrinsic camera parameters

    Page(s): 121 - 124
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (144 KB)  

    This paper presents a simple and analytical procedure for calibrating extrinsic camera parameters. First, a calibration equation that separates rotational and translational parameters is given. The calibrating equation involves only rotational parameters and requires no absolute position information. A four-point calibration procedure is proposed that involves three points on a line and one point out of the line, and leads to four possible calibration solutions, obtained analytically. Additional steps required to eliminate false solutions are also discussed. Once the true rotational parameters are identified, the translational parameters are obtained analytically and uniquely with additional absolute position information. The required absolute position information appears in a simple and explicit form. For extrinsic calibration among multiple cameras, such as stereo cameras, it is easy to show that the absolution position information is not needed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Profile sensing with an actuated whisker

    Page(s): 124 - 127
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (384 KB)  

    Obstacle avoidance and object identification are important tasks for robots in unstructured environments. This paper develops an actuated whisker that determines contacted object profiles using a hub load cell. The shape calculation algorithm numerically integrates the elastica equations from the measured hub angle, displacement, forces, and torque until the bending moment vanishes, indicating the contact point. Sweeping the whisker across the object generates a locus of contact points that can be used for object identification. Experimental results demonstrate the ability to identify and differentiate square and curved objects at various orientations. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stratified motion planning on nonsmooth domains with robotic applications

    Page(s): 128 - 132
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (248 KB)  

    This paper presents an extension of stratified motion planning results to the case where the base manifold upon which the motion planning occurs is not smooth. Robotic applications of this work include motion planning for legged robots over known, nonsmooth terrain and manipulation of nonsmooth objects with multiple robotic manipulators. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stiffness and contact mechanics for soft fingers in grasping and manipulation

    Page(s): 132 - 135
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (224 KB)  

    In this paper, nonlinear stiffness of contact for soft fingers, commonly used in robotic grasping and manipulation, under a normal load is studied. Building upon previous research results of soft-finger contact expressed in the power-law equation, the equation for the nonlinear stiffness of soft contact was derived. This new theory relates the approach displacement (or the vertical depression) of soft fingertips with respect to the normal force applied. The nonlinear contact stiffness is found to be the product of an exponent and the ratio of the normal force versus approach displacement. Stiffness relationship of Hertzian contact for linear elastic materials is shown to be a special case of the general theory presented in this paper. Experimental results are used to validate the theoretical analysis. In addition, potential applications to fixturing are discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Consistency verification in modeling of real-time systems

    Page(s): 136 - 142
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (304 KB)  

    To real-time system designers, end-to-end time delay between external inputs and outputs is among the most important constraints. To ensure these system-wide constraints are satisfied, each of the constituent components is subject to a set of derived intermediate constraints. Since the system-wide constraints allow many possibilities for the intermediate constraints based on design tradeoffs, an important issue is how to guarantee the consistency between system-wide constraints and intermediate component constraints. In this paper, we present a systematic method for the verification of consistency between a system's global timing constraints and intermediate component constraints. The essence of this technique is to construct a timing model for each component, based on component constraints. This model treats a component as a black box. When replacing each component with its timing model, we obtain a complete time Petri net model for system architecture, which allows us to verify the consistency between global and component constraints. The key contribution is twofold. First, our technique of verification is efficient by supporting incremental analysis and suppressing internal state space of components. Second, much of the verification process presented in this paper can be automated. We illustrate the consistency verification process through a flexible manufacturing system example. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Uncalibrated dynamic visual servoing

    Page(s): 143 - 147
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (240 KB)  

    A dynamic quasi-Newton method for uncalibrated, vision-guided robotic tracking control with fixed imaging is developed and demonstrated. This method does not require calibrated kinematic and camera models. Robotic control is achieved at each step through minimizing a nonlinear objective function, by taking quasi-Newton steps and estimating the composite Jacobian at each step. The Jacobian is estimated using a dynamic recursive least-squares algorithm. Experimental results demonstrate the validity of this approach. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stability and four-posture control for nonholonomic mobile robots

    Page(s): 148 - 154
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (376 KB)  

    In this paper, a four-posture control for nonholonomic mobile robots is proposed. Based upon posture velocity error dynamics, the empirical kinematic motion requirements of a mobile robot are proposed, and the four-posture control is designed in order to generate the robustly required moving trajectory with posture error reduction. The controller is designed with four possible moving directions of linear and angular velocities. The robustness of the controller is confirmed using Lyapunov stability theory. The proposed controller is experimentally demonstrated under high velocity and acceleration conditions with different control parameters. It is shown that the four-posture control algorithm is effective and feasible, even if an unsophisticated velocity controller is used as the deriving unit of a mobile robot. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Path-tracking of a tractor-trailer vehicle along rectilinear and circular paths: a Lyapunov-based approach

    Page(s): 154 - 160
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (288 KB)  

    The problem of asymptotic stabilization for straight and circular forward/backward motions of a tractor-trailer system is addressed using Lyapunov techniques. Smooth, bounded, nonlinear control laws achieving asymptotic stability along the desired path are designed, and explicit bounds on the region of attraction are provided. The problem of asymptotic controllability with bounded control is also addressed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Task-space tracking control of robot manipulators via quaternion feedback

    Page(s): 160 - 167
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (568 KB)  

    In this paper, we consider the problem of task-space tracking control of robot manipulators. Based on a quaternion representation of the end-effector orientation, we design a class of task-space controllers that ensure asymptotic end-effector position and orientation tracking. To facilitate the control design, we first develop model-based and adaptive full-state feedback controllers. We then present a model-based output feedback controller that eliminates link velocity measurements via a model-based observer. The application of the proposed control strategy to redundant robots is also discussed. Simulation results based on a six-link manipulator system are presented for the output feedback controller. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Eighth International Conference on Control Automation Robotics and Vision

    Page(s): 168
    Save to Project icon | Request Permissions | PDF file iconPDF (703 KB)  
    Freely Available from IEEE
  • IEEE Member Digital Library [advertisement]

    Page(s): 169
    Save to Project icon | Request Permissions | PDF file iconPDF (178 KB)  
    Freely Available from IEEE
  • Proceedings of the IEEE celebrating 92 years of in-depth coverage on emerging technologies

    Page(s): 170
    Save to Project icon | Request Permissions | PDF file iconPDF (319 KB)  
    Freely Available from IEEE

Aims & Scope

This Transactions ceased production in 2004. The current retitled publications areIEEE Transactions on Automation Science and Engineering and IEEE Transactions on Robotics.

Full Aims & Scope