Robotics Automation Research Papers - Academia.edu (original) (raw)

U nmanned aerial vehicles (UAVs) can be used to cover large areas searching for targets. However, sensors on UAVs are typically limited in their accuracy of localization of targets on the ground. On the other hand, unmanned ground vehicles (UGVs) can be deployed to accurately locate ground targets, but they have the disadvantage of not being able to move rapidly or see through such obstacles as buildings or fences. In this article, we describe how we can exploit this synergy by creating a seamless network of UAVs and UGVs. The keys to this are our framework and algorithms for search and localization, which are easily scalable to large numbers of UAVs and UGVs and are transparent to the specificity of individual platforms. We describe our experimental testbed, the framework and algorithms, and some results.

In this paper we consider the problem of simultaneously localizing all members of a team of robots. Each robot is equipped with proprioceptive sensors and exteroceptive sensors. The latter provide relative observations between the robots. Proprioceptive and exteroceptive data are fused with an Extended Kalman Filter. We derive the equations for this estimator for the most general relative observation between two robots. Then we consider three special cases of relative observations and we present the structure of the filter for each case. Finally, we study the performance of the approach through many accurate simulations.

- by Roland Siegwart
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- General Relativity, Kalman Filter, Sensor Fusion, Extended Kalman Filter

We address scaling of the "dynamic systems" approach for robot planning to multi-agent cooperation. To accommodate this extension it is necessary to carefully consider how individual behaviors contribute to the vector field. To avoid spun"ous minima and related pro biems a competition dynamics is introduced and its stability is analyzed. A system of two cooperating agents is designed, and examples are presented to illustrate the utility of this approach.

- by Henrik Christensen
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- Engineering, Computer Science, Computational Geometry, Intelligent Control
- by Ruzena Bajcsy
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- Computational Geometry, Intelligent Control, Stability, Control Systems

In this paper, a vision-based stabilization and output tracking control method for a four-rotor helicopter has been proposed. A novel 2 camera method has been described for estimating the full 6 DOF pose of the helicopter. This two camera system is consisting of a pan-tilt ground camera and an onboard camera. The pose estimation algorithm is compared in simulation to other methods (such as four point method, and a stereo method) and is shown to be less sensitive to feature detection errors on the image plane. The proposed pose estimation algorithm and nonlinear control techniques have been implemented on a remote controlled quadrotor helicopter.

- by Laith AbuAssi
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- Stability, Tracking, Feature Detection, Feedback
- by Luigi Pagliarini
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- Control Systems, LEGO Mindstorms, Mobile Robots, Robot kinematics

We present the design and implementation of a real-time computer vision system for a rotorcraft unmanned aerial vehicle to land onto a known landing target. This vision system consists of customized software and off-the-shelf hardware which perform image processing, segmentation, feature point extraction, camera pan/tilt control, and motion estimation. We introduce the design of a landing target which significantly simplifies the computer vision tasks such as corner detection and correspondence matching. Customized algorithms are developed to allow for realtime computation at a frame rate of 30 Hz. Such algorithms include certain linear and nonlinear optimization schemes for model-based camera pose estimation. We present results from an actual flight test which show the vision-based state estimates are accurate to within 5 cm in each axis of translation, and 5 degrees in each axis of rotation, making vision a viable sensor to be placed in the control loop of a hierarchical flight management system.

This paper presents fast algorithms for penetration and contact determination between general polyhedral models in dynamic environments. The main contribution is an extension of an earlier expected constant time algorithm between convex polytopes to detect penetrations and contacts. For each pair of non-convex polyhedral models, the algorithm uses the convex hull of each object to determine which regions of the objects are colliding. After identifying these regions, it uses a new dynamic technique, sweep and prune, to overcome the bottleneck of O(n 2) pairwise feature checks of these regions. The resulting algorithm has been implemented and in practice its performance in dynamic environments is O(n + m), where m corresponds to the number of feature pairs close to each other.

- by Ming C. Lin
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- Mathematics, Computer Science, Computer Graphics, Computational Geometry

An automatic method for generating assembly instructions using CAD files is presented in this paper. Algorithms for extracting geometrical information of objects stored in a non-proprietary format, ISO-10303, STEP-CAD data file are explained. The developed algorithms form an important link between design and manufacturing. In our previous work, we designed a hierarchical assembly model that allows designers to evaluate products for manufacturing cost using a structured assembly coding system (SACS). Each SACS code represents a sequence of assembling/disassembling operations for mating two parts. The developed algorithms in this paper will generate the required SACS codes based on the geometrical and topological information extracted from the STEP files of a product in a CAD environment. Based on the generated SACS codes, the proper assembly operations can then be derived for assembling the designed product. An example of assembly with simple parts is presented to verify the method.

- by Swee Mok
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- Engineering, Computer Science, Production, Product Design
- by Simone Gasparini
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- Path planning, Geometry, Mobile Robots, Mobile Robot
- by Andrew Ceranowicz
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- Engineering, Computer Science, Path planning, Virtual Reality

The authors examine some issues in the transfer function modeling of a single flexible link. Using the assumed-modes approach, it is possible to find the transfer function between the torque input and the net tip deflection. It is shown that when the number of modes is increased for more accurate modeling, the relative degree of the transfer function becomes ill-defined.

- by David Wang
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- Mechanical Engineering, Controller Design, Control system, Robotic

Developing easy to use, intuitive interfaces is crucial to introduce robotic automation to many small medium sized enterprises (SMEs). Due to their continuously changing product lines, reprogramming costs exceed installation costs by a large margin. In addition, traditional programming methods for industrial robots is too complex for an inexperienced robot programmer, thus external assistance is often needed. In this paper a new incremental multimodal language, which uses augmented reality (AR) environment, is presented. The proposed language architecture makes it possible to manipulate, pick or place the objects in the scene. This approach shifts the focus of industrial robot programming from coordinate based programming paradigm, to object based programming scheme. This makes it possible for non-experts to program the robot in an intuitive way, without going through rigorous training in robot programming.

Operational safety and health monitoring are critical niatters for autonomous field mobile robots such as plnrietriry rovers operating on challenging terrain. This paper describes relevant rover safety and health issues arid presents an approach to maintaining vehicle safe01 in a nrivigational context. The proposed rover safe@ module is coinposed if two distinct components: snfe cittitiide (pitch and roll) management and safe trcictiori management. Fuzzy logic approaches to reasoning about safe attitude and traction management are presented, wherein sensing if safety status and perception qf terrain quality are used to infer safe speeds of traversal. Results of field tests and laboratory experiments are also described. The approach provides an intrinsic safety cognizance and a capacity for reactive mitigation of nnvigation risks.

- by E. Tunstel
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- Engineering, Computer Science, Quality Management, Fuzzy Logic

Physical textiles implementations 12 Mechanical modeling requires the physical modeling and simulation of complex phenomena of textiles within the scope of the multi-scale and physical textiles approach. This means implementation in textiles and management of modeling and optimization methods and tools, which are combined into a systematic approach. The major is aimed at students in textile mechanics who wish to open their minds to

- by Elsayed Elnashar
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- Robotics Automation

Fire fighters extinguish fires to protect lives and to avoid destruction of property and environment. Through extinguishing operation, many firefighters are killed and injured due to the absence of information about hazard building infrastructure. In this paper, we design and implement a prototype robotic system which intends to assist the firefighters in accomplishing their duties, including navigation, rescue, and obtain localization information. In addition, the robotic system will navigate the firefighters through the safest route inside the building where GPS signals are inaccessible.

- by Tareq Alhmiedat
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- Robotics Automation

A virtual control environment for robot teleoperation via the Internet is presented. It comprises a Java3D-based real-time virtual representation of the robot and worksite, and uses a graphic panel, an environment for remote robot programming, and a dataglove with a 6D position tracker as the control interfaces. The use of Virtual Reality (VR) techniques for Internet teleoperation allow: (1) time delays inherent in IP networks to be suppressed, and the operator's work to be simplified and accelerated, compared to methods that use delayed TV images. The system realisation, with its use of open technologies Java, Java3D and 3-tier client/server architecture, provides portability among different computer platforms and types of robots. The efficiency of the VR-based methods developed has been verified for slow communication rates (0.1-0.5 KB/sec), where TVbased control methods are inapplicable. VR systems have been developed for the WWW-based control of the PUMA and CRS industrial robot manipulators. The particulars of these systems, the experiments undertaken, current issues, and directions of future work are presented.

- by Chellali Ryad
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- Virtual Reality, Time Delay, Industrial Robots, Real Time
- by Yoshihiko Nakamura
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- Stability, Uncertainty, Non Linear Programming, Robot kinematics

Unmanned aerial vehicles (UAVs) or unmanned aircraft systems (UASs) are synonymous with drones and are used interchangeably; its many avatars having the same meaning. This paper covers how advancement in technology has enhanced the features of the drone in scope and scale to specific functions demanded across a spectrum of industries. By presenting a review of the application of drones as a cost-effective option, a variety of purposes in various industries is served as well. By using a host of sensors, vision system, and micro-controllers onboard coupled with IoT, the effectiveness of drones in collecting, analyzing, and providing data has increased multifold, upgrading existing usage and throwing open new avenues of applications. To alleviate the possibilities of the transport-related congestion and its consequences, developments in the Internet of Drones (IoD) architecture and system are studied for seamless operations, to manage the heavy traffic of drones envisaged in their airw...

- by Shubham Nagar
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- Robotics, Computer Science, Unmanned Aerial Vehicle (UAV), Drones

A flexible needle can be accurately steered by robotically controlling the orientation of the bevel tip as the needle is inserted into tissue. Here, we demonstrate the significant effect of friction between the long, flexible needle shaft and the tissue, which can cause a significant discrepancy between the orientation of the needle tip and the orientation of the base where the needle is controlled. Our experiments show that several common phantom tissues used in needle steering experiments impart substantial frictional forces to the needle shaft, resulting in a lag of over 45° for a 10 cm insertion depth in some phantoms; clinical studies have reported torques large enough to could cause similar errors during needle insertions. Such angle discrepancies will result in poor performance or failure of path planners and image-guided controllers, since the needles used in percutaneous procedures are too small for state-of-the-art imaging to accurately measure the tip angle. To compensate...

- by Kyle Reed
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- Automatic Control, Path planning, Biomedical Imaging, Mobile Robots

This paper describes a new collision detection algorithm designed for interactive manipulation in virtual environments. Making some assumptions on objects motion, the collision time between two objects can be computed by solving a... more

- by Stephane Redon and +1
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- Virtual Environment, Collision detection, Robotics Automation

Abstract—Intelligent wheelchairs operating in dynamic environments need to sense its neighborhood and adapt the control signal, in real-time, to avoid collisions and protect the user. In this paper we propose a robust, real-time obstacle avoidance extension of the classic potential field methodology. Our algorithm is specially adapted to share the wheelchair’s control with the user avoiding risky situations. This method relies on the idea of virtual forces, generated by the user command (attractive force) and by the objects detected on each ultrasonic sensor (repulsive forces), acting on the wheelchair. The resultant wheelchair’s behavior is obtained by the sum of the attractive force and all the repulsive forces at a given position. Experimental results from drive tests in a cluttered office environment provided statistical evidence that the proposed algorithm is effective to reduce the number of collisions and still improve the user’s safety perception. Keywords—Intelligent wheelc...

- by Rodrigo Braga
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- Robotics, Artificial Intelligence, Control Systems, Safety

This paper presents a design overview of a novel high DoF (Degrees-of-Freedom) system being developed for minimally invasive surgery of the throat. The system is designed to allow remote operation of 2-3 tools with high tip dexterity to enable suturing and soft-tissue manipulation while using the patient's mouth as the only entry port. The slave is a 34 DoF unit equipped with three snake-like distal dexterity units for surgical tool manipulation. Each of these units is a multi-backbone snakelike mechanism equipped with a detachable milli parallel manipulator allowing interchangeable tools to be used. The paper presents the outline of the kinematic analysis of the snake-like units and proposes one possible actuation redundancy resolution to allow further downsize scalability while reducing the risk of buckling of the primary backbone of the snake-like units. Finally, the paper presents a first early experiment with a prototype of the snake-like unit.

- by Nabil Simaan
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- Soft Tissue, Kinematic Analysis, Degree of Freedom, Robotics Automation

The Autonomous Systems Laboratory is in the midst of developing an advanced underwater robotic technology test platform. The platform consists of the Omni-Directional Intelligent Navigator (ODIN) and the Integrated Graphic Workstation (IGW). ODIN is a six degree-of-freedom (dof) underwater vehicle with dual operational modes (autonomous and tethered) and a single dof mechanical manipulator. IGW is a real-time, 3-dimensional graphic monitoring, testing, and evaluation workstation. This paper presents ODIN's mechanical and electrical specifications; its vehicle dynamics and depth control system; its recent simulation and experimental results; and IGW's specifications

- by Jose Rodriguez Sanchez
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- Mechanical Engineering, Vehicle Dynamics, Control system, Real Time

A new approach to the fault-accommodating allocation of thruster forces of an autonomous underwater vehicle (AUV) is investigated in this paper. This paper presents a framework that exploits the excess number of thrusters to accommodate thruster faults during operation. First, a redundancy resolution scheme is presented that considers the presence of an excess number of thrusters along with any thruster

Sandia National Laboratories has developed an approach to the design, evaluation, deployment and operation of intelligent systems which is called System Composer. This toolkit provides an infrastructure and architecture for robot and automation system users to readily integrate system components and share mechatronic, sensor, and information resources over networks. The technology described in this paper provides a framework for real-time collaboration between researchers, manufacturing entities, design entities, and others without regard to relative location. An overview of the toolkit including its elements and architecture is provided along with examples of its use. * This work was performed at Sandia National Laboratories supported by the United States Department of Energy under contract number DE-AC04-94AL85000. R DISCLAIMER Portions ofthis document may be illegible in electronic image products. Images are produced from the best available original dOCUXIlent,

- by Brady Davies
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- Mechatronics, Computer Networks, System Integration, CAD

We present control methods for an autonomous four-rotor helicopter, called a quadrotor, using visual feedback as the primary sensor. The vision system uses a ground camera to estimate the pose (position and orientation) of the helicopter. Two methods of control are studied one using a series of mode-based, feedback linearizing controllers, and the other using a backstepping-like control law. Various simulations of the model demonstrate the implementation of feedback linearization and the backstepping controllers. Finally, we present initial flight experiments where the helicopter is restricted to vertical and yaw motions.

- by James P Ostrowski
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- Visual Feedback, Feedback Linearization, Robotics Automation, Control Method

The authors review the most important past and ongoing research projects in macro-robotics, micro-robotics and bio-robotics, three general areas of robotics which have the potential to provide significant improvements to the state of the art of medical technology. A brief analysis of the economic potentialities of robotics in medicine is also provided.

- by Maria Chiara Carrozza
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- Mechanical Engineering, Surgery, Economics, Mechatronics

Nano-robots are the robots that are simply known as that controllable machine at the nano (10 -9 ) meter or molecular scale, composed of nano-components. More specifically, nano robotics refers to the still largely hypothetical nanotechnology engineering discipline of designing and building nano robots. Even though the field of nano robotics is fundamentally different from that of the macro robots due to the differences in scale and material, there are many similarities in design and control techniques that eventually could be projected and applied. Due to the modern scientific capabilities, it has become possible to attempt the creation of nano robotic devices and interface them with the macro world for control. There are countless such machines which exist in nature and there is an opportunity to build more of them by mimicking nature. Nowadays these nano robots play a vital role in the field of Bio Medicine. Especially in the treatment of cancer, Cerebral Aneurysm, kidney stones removal, also to remove the defected part in our DNA structure and some other treatments that has the greatest aid to save human lives. This paper guides to the recent research on nano robots in the Bio medical applications.

- by R.B.Durai Raj
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- Robotics Automation

The structure of the kinematic and dynamic models of wheeled mobile robots is analyzed. It is shown that, for a large class of possible configurations, they can be classified into five types, characterized by generic structures of the... more

- by Lefteris Doitsidis
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- Mechanical Engineering, Fuzzy Logic, Path planning, Mobile Robots

Origami, the human art of paper sculpture, is a fresh challenge for the field of robotic manipulation, and provides a concrete example for many difficult and general manipulation problems. This paper presents some initial results, including the world's first origami-folding robot, definition of a simple class of origami for which we have designed a complete automatic planner, an analysis of the kinematics of more complicated folds, and some new theorems about foldability.

- by Devin Balkcom
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- Fast Food, Robot Manipulator, Robotics Automation, Space Telescope

In this paper, an adaptive control method for trajectory tracking of robot manipulators, based on new neuro-fuzzy modelling is presented. The proposed control scheme uses a three-layer neural fuzzy network (NFN) to estimate system uncertainties. The function of robot system dynamics is first modelled by a fuzzy system, which in the sequel is approximated by a combination of high order neural networks (HONNs). The overall representation is linear in respect to the unknown NN weights leading to weight adaptation laws that ensure stability and convergence to unique global minimum of the error functional. Due to the adaptive neurofuzzy modelling, the proposed controller is independent of robot dynamics, since the free parameters of the neuro-fuzzy controller are adaptively updated to cope with changes in the system and the environment. Adaptation laws for the network parameters are derived, which ensure network convergence and stable control. A weight hopping technique is also introduced to ensure that the estimated weights stay within pre-specified bounds. The simulation results show very good approximation performance of the proposed representation as compared with a simple NN approximator and very good tracking abilities under disturbance torque compared to conventional computed torque PD control.

- by Dimitris Theodoridis
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- Engineering, Neuro Fuzzy, Robotics Automation

The latest technological progress in sensors, actuators and energy storage devices enables the developments of miniature VTOL 1 systems. In this paper we present the results of two nonlinear control techniques applied to an autonomous micro helicopter called Quadrotor. A backstepping and a sliding-mode techniques. We performed various simulations in open and closed loop and implemented several experiments on the test-bench to validate the control laws. Finally, we discuss the results of each approach. These developments are part of the OS4 2 project in our lab.

- by Laith AbuAssi
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- Robotics, Autonomous Robotics, Aerial Robotics, Nonlinear Control

A simple and efficient randomized algorithm is presented for solving single-query path planning problems in high-dimensional configuration spaces. The method works by incrementally building two Rapidly-exploring Random Trees (RRTs) rooted at the start and the goal configurations. The trees each explore space around them and also advance towards each other through the use of a simple greedy heuristic. Although originally designed to plan motions for a human arm (modeled as a 7-DOF kinematic chain) for the automatic graphic animation of collision-free grasping and manipulation tasks, the algorithm has been successfully applied to a variety of path planning problems. Computed examples include generating collision-free motions for rigid objects in 2D and 3D, and collision-free manipulation motions for a 6-DOF PUMA arm in a 3D workspace. Some basic theoretical analysis is also presented.

- by Steven Lavalle
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- Computer Science, Animation, Computational Geometry, Path planning

This paper proposes a method for the visual-based navigation of a mobile robot in indoor environments, using a single omni-directional (catadioptric) camera. The geometry of the catadioptric sensor and the method used to obtain a bird's eye (orthographic) view of the ground plane are presented. This representation significantly simplifies the solution to navigation problems, by eliminating any perspective effects.

- by Jose Gaspar
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- Mechanical Engineering, Topology, Motion Planning, Path planning

Recent progress in sensor technology, data processing and integrated actuators has made the development of miniature flying robots fully possible. Micro VTOL 1 systems represent a useful class of flying robots because of their strong capabilities for small-area monitoring and building exploration. In this paper we describe the approach that our lab 2 has taken to micro VTOL evolving towards full autonomy, and present the mechanical design, dynamic modelling, sensing, and control of our indoor VTOL autonomous robot OS4 3 .

- by Laith AbuAssi
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- Data Processing, Robotics Automation

In this paper, a combined adaptive-robust and neural network control based on backstepping design is proposed for trajectory tracking of two 6-DOF rigid link electrically driven (RLED) elbow robot manipulators moving a rigid object when actuator dynamics is also considered in the system dynamics. First, the authors derive kinematics and dynamics of the mechanical subsystem and the relations among forces/moments acting on the object by the robots, using different Jacobians. Second, the current vector (instead of the torque vector) is regarded as the control input for the mechanical subsystem and, using an adaptive-robust algorithm, an embedded control variable for the desired current vector is designed so that the tracking goal may be achieved. Third, using a neural network controller for DC motor dynamics, the voltage commands are designed such that the joint currents track their desired values. The proposed control algorithm does not require exact knowledge of the mathematical model representing each robot and its actuator dynamics and does not need acceleration measurement. The adaptive-robust control parameters and neural weights are adapted online, and the related Lyapunov function is established and verified. The proposed combined controller guarantees asymptotic tracking of the object desired trajectory. Simulation results show the efficiency and usefulness of the proposed scheme.

- by Mohammad Eghtesad
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- Engineering, Adaptive Control, Robust control, Neural Network

The ability to simultaneously localise a robot and accurately map its surroundings is considered by many to be a key prerequisite of truly autonomous robots. This paper presents a real-world implementation of FastSLAM, an algorithm that recursively estimates the full posterior distribution of both robot pose and landmark locations. In particular, we present an extension to FastSLAM that addresses the data association problem using a nearest neighbour technique. Building on this, we also present a novel multiple hypothesis tracking implementation (MHT) to handle uncertainty in the data association. Finally an extension to the multi-robot case is introduced. Our algorithm has been run successfully using a number of data sets obtained in outdoor environments. Experimental results are presented that demonstrate the performance of the algorithms when compared with standard Kalman Filter-based approaches.

- by Juan Nieto
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- Kalman Filter, Data Association, Real-Time Data Processing, Nearest Neighbour

Recent developments on micro/nano manipulation and internet technologies allow potential impacts on networkedmicro-automation of small industrial products. However, reliable and efficient tele-micromanipulation systems with haptic feedback over the Internet face to strong problems due to the nonlinear nature of microenvironment and time-varying delays in communication lines. Towards this end, this paper presents a robust bilateral controller design using H ∞ -optimal control and µ-synthesis frameworks. This approach allows a convenient means of tradeoff the optimization of various performance criteria (micro scale force/position) and robustness for a prespecified time-delay margin and force scaling factors. The validity of the proposed method is demonstrated by simulations and experiments for a pick-and-place micromanipulation task. 0-7803-8232-3/04/$17.00 ©2004 IEEE np nf G J J , µ ρ J nf np γ J ρ J J g , np nf np nf

- by Jean-guy Fontaine
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- Optimal Control, Controller Design, Time Delay, Internet technology

In this work, a dynamic graphical model of operating modes of intelligent and autonomous multi inputs multi outputs (MIMO) vehicles is presented. This study shows the feasibility of improving the traffic management and decision inside confined space according to the operating situation of each involved vehicle. The proposed dynamic graphical model depends on the on-line monitoring outputs of the vehicles' actuators. These outputs correspond to the dynamic model based residuals of the actuators. Co-simulation using experimental data show the interest of the developed model.

- by Wissam KHALIL
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- Operations Management, Graph Theory, Vehicle Dynamics, Graphical Models

In this paper the design and the experimental verification of a Constrained Finite Time Optimal (CFTO) control scheme for the attitude control of an Unmanned Quadrotor Helicopter (UqH) subject to wind gusts is being presented. In the proposed design the UqH has been modeled by a set of Piecewise Affine (PWA) linear equations while the wind gusts effects are embedded in the system model description as the affine terms. In this approach the switching among the PWA model descriptions are ruled by the rate of the rotation angles. In the design of the stabilizing CFTO-controller both the magnitude of external disturbances (worst case applied wind gust), and the mechanical constraints of the UqH such as maximum thrust in the rotors and UqH's angles rate are taken under consideration in order to design an off-line controller that could rapidly be applied to a UqH in a form of a look-up table. The proposed control scheme is applied in experimental studies and multiple test-cases are presented that prove the efficiency of the proposed scheme.

- by Kostas Alexis
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- Optimal Control, Atmospheric Modeling, Multiple testing, Sliding mode control

This paper describes the designing of a nonlinear biological controller inspired from stable human gait locomotion, which we implement for a stable biped motion on a Biped Robot. The design of a Central Pattern Generator (CPG) which consists of a four coupled Rayleigh Oscillators. A Two-Way oscillator coupling has been used for modeling the CPG. The parameters of the CPG are then optimized by Genetic Algorithm (GA) to match with the stable human gait oscillation. The stable human gait oscillation data was obtained using the Intelligent Gait Oscillation Detector (IGOD) biometric suit, which simultaneously measures both the human hips and knee oscillations. After checking the Limit Cycle behavior of the CPG it has been successfully simulated on the Spring Flamingo robot in YOBOTICS environment.

- by Soumik Mondal
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- Engineering, Robotics Automation

In this paper, a nonlinear model associated to the fast switching on-off solenoid valve and pneumatic cylinder is dynamically presented. Furthermore, the electrical, magnetic, mechanical, and fluid sub-systems are studied. Two common control policies to track valve position, a proportional integrator (PI) based on pulse width modulation (PWM) and hysteresis controllers, are investigated. The control cylinder position is simulated usinga programmable logic controller (PLC), andan experimental setup regulated with AVR microcontroller isaccomplished. Simulationand experimental results verified proper performance of the proposed controller.

- by ali mohammadi
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- Engineering, Robotics Automation

We present a replanning algorithm for repairing Rapidly-exploring Random Trees when changes are made to the configuration space. Instead of abandoning the current RRT, our algorithm efficiently removes just the newly-invalid parts and maintains the rest. It then grows the resulting tree until a new solution is found. We use this algorithm to create a probabilistic analog to the widely-used D* family of deterministic algorithms, and demonstrate its effectiveness in a multirobot planning domain.

- by Dave Ferguson
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- Path planning, Probability, Space Exploration, Navigation

- by Srishti Bhardwaj
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- Data Processing, Robotics Automation

This paper presents a multi-vehicle platform and framework for robotics education and research. The system is designed as an educational tool for introducing children to engineering and robotics and is composed of hardware and software components that allow users to easily design and implement sophisticated robotic behaviors. We formally introduce the robotic game Marco Polo as a problem that mimics the pursuit-evasion game often played by children in swimming pools. Specifically, we address the question of finding a pursuit strategy under the condition of intermittent communication. Finally, we present an implementation of the Marco Polo game.

- by Rafael Fierro
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- Mathematics, Human Computer Interaction, Control Systems, Path planning