The Experts below are selected from a list of 17874 Experts worldwide ranked by ideXlab platform

Hyouk Ryeol Choi - One of the best experts on this subject based on the ideXlab platform.

  • Differential Drive in pipe robot for moving inside urban gas pipelines
    IEEE Transactions on Robotics, 2005
    Co-Authors: Segon Roh, Hyouk Ryeol Choi
    Abstract:

    Pipelines for the urban gas-supply system require a robot possessing outstanding mobility and advanced control algorithms, since they are configured with various pipeline elements, such as straight pipelines, elbows, and branches. We present a comprehensive work for moving inside underground urban gas pipelines with a miniature Differential-Drive in-pipe robot, called the Multifunctional Robot for IN-pipe inSPECTion (MRINSPECT) IV. MRINSPECT IV has been developed for the inspection of urban gas pipelines with a nominal 4-in inside diameter. The mechanism for steering with Differential-Drive wheels, arranged three-dimensionally, allows it to easily adapt to most of the existing configurations of pipelines, as well as providing excellent mobility during navigation. After carrying out analysis for fittings in pipelines, mathematical descriptions of their geometries are presented, which make it possible to estimate the movement patterns of the robot while passing through the fittings. Also, we propose a method of controlling the robot by modulating speeds of driving wheels that is applicable without sophisticated sensory information. To confirm the effectiveness of the proposed method, experiments are performed, and supplementary considerations on the design of the in-pipe robot are discussed.

  • Differential-Drive in-pipe robot for moving inside urban gas pipelines
    IEEE Transactions on Robotics, 2005
    Co-Authors: Segon Roh, Hyouk Ryeol Choi
    Abstract:

    Pipelines for the urban gas-supply system require a robot possessing outstanding mobility and advanced control algorithms, since they are configured with various pipeline elements, such as straight pipelines, elbows, and branches. We present a comprehensive work for moving inside underground urban gas pipelines with a miniature Differential-Drive in-pipe robot, called the Multifunctional Robot for IN-pipe inSPECTion (MRINSPECT) IV. MRINSPECT IV has been developed for the inspection of urban gas pipelines with a nominal 4-in inside diameter. The mechanism for steering with Differential-Drive wheels, arranged three-dimensionally, allows it to easily adapt to most of the existing configurations of pipelines, as well as providing excellent mobility during navigation. After carrying out analysis for fittings in pipelines, mathematical descriptions of their geometries are presented, which make it possible to estimate the movement patterns of the robot while passing through the fittings. Also, we propose a method of controlling the robot by modulating speeds of driving wheels that is applicable without sophisticated sensory information. To confirm the effectiveness of the proposed method, experiments are performed, and supplementary considerations on the design of the in-pipe robot are discussed.

Matthew T. Mason - One of the best experts on this subject based on the ideXlab platform.

  • for Differential-Drive Mobile Robots
    2009
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    The shortest paths for a mobile robot are a fundamental property of the mechanism, and may also be used as a family of primitives for mo- tion planning in the presence of obstacles. This paper characterizes shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest, the total amount of wheel-rotation is optimized. Using the Pontrya- gin Maximum Principle and other tools, we derive the set of optimal paths, and we give a representation of the extremals in the form of finite automata. It turns out that minimum time for the Reeds-Shepp car is equal to minimum wheel-rotation for the Differential-Drive, and minimum time curves for the convexified Reeds-Shepp car are exactly the same as minimum wheel-rotation paths for the Differential-Drive. It is currently unknown whether there is a simpler proof for this fact. KEY WORDS—optimal control, nonholonomic constraints, shortest paths (or geodesics), Differential Drive, mobile robot

  • Minimum Wheel-Rotation Paths for Differential-Drive Mobile Robots
    The International Journal of Robotics Research, 2009
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    The shortest paths for a mobile robot are a fundamental property of the mechanism, and may also be used as a family of primitives for motion planning in the presence of obstacles. This paper characterizes shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest, the total amount of wheel-rotation is optimized. Using the Pontryagin Maximum Principle and other tools, we derive the set of optimal paths, and we give a representation of the extremals in the form of finite automata. It turns out that minimum time for the Reeds-Shepp car is equal to minimum wheel-rotation for the Differential-Drive, and minimum time curves for the convexified Reeds-Shepp car are exactly the same as minimum wheel-rotation paths for the Differential-Drive. It is currently unknown whether there is a simpler proof for this fact.

  • minimum wheel rotation paths for Differential Drive mobile robots
    International Conference on Robotics and Automation, 2006
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    Characterizing optimal paths for mobile robots is an interesting, important, and challenging endeavor. Not only they are interesting with respect to the optimized criteria, but also they offer a family of motion primitives that can be used for motion planning in the presence of obstacles. This paper presents characterization of shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest., the total amount of wheel rotation is optimized. Using Pontryagin maximum principle and other tools, we establish the existence of optimal trajectories, and derive the set of optimal paths. Some Reeds-Shepp curves appear in the set of optimal paths, whereas there are optimal paths which are different from Reeds-Shepp curves. To the best of our knowledge, this is the first progress on the problem

  • Time Optimal Trajectories for Bounded Velocity Differential Drive Vehicles
    The International Journal of Robotics Research, 2002
    Co-Authors: Devin J. Balkcom, Matthew T. Mason
    Abstract:

    This paper presents the time optimal trajectories for Differential Drive vehicles in the unobstructed plane. The wheel angular velocities are bounded, but may be discontinuous. The paper proves the existence of optimal controls, derives the structure of optimal trajectories, and develops an algorithm for producing a time optimal trajectory between any two configurations. Every nontrivial optimal trajectory is composed of straight segments alternating with turns about the robot's center. Optimal trajectories may have as many as five actions, but four actions are sufficient—for every optimal trajectory of five actions, there is an equally fast trajectory with four actions.

  • ICRA - Extremal trajectories for bounded velocity Differential Drive robots
    Proceedings 2000 ICRA. Millennium Conference. IEEE International Conference on Robotics and Automation. Symposia Proceedings (Cat. No.00CH37065), 2000
    Co-Authors: Devin Balkcom, Matthew T. Mason
    Abstract:

    This paper applies Pontryagin's maximum principle to the time optimal control of Differential Drive mobile robots with velocity bounds. The maximum principle gives necessary conditions for time optimality. Extremal trajectories are those which satisfy these conditions, and are thus a superset of the time optimal trajectories. This paper derives a compact geometrical structure for extremal trajectories and shows that extremal trajectories are always composed of rotations about the robot center and straight line motions. Further necessary conditions are obtained.

Segon Roh - One of the best experts on this subject based on the ideXlab platform.

  • Differential Drive in pipe robot for moving inside urban gas pipelines
    IEEE Transactions on Robotics, 2005
    Co-Authors: Segon Roh, Hyouk Ryeol Choi
    Abstract:

    Pipelines for the urban gas-supply system require a robot possessing outstanding mobility and advanced control algorithms, since they are configured with various pipeline elements, such as straight pipelines, elbows, and branches. We present a comprehensive work for moving inside underground urban gas pipelines with a miniature Differential-Drive in-pipe robot, called the Multifunctional Robot for IN-pipe inSPECTion (MRINSPECT) IV. MRINSPECT IV has been developed for the inspection of urban gas pipelines with a nominal 4-in inside diameter. The mechanism for steering with Differential-Drive wheels, arranged three-dimensionally, allows it to easily adapt to most of the existing configurations of pipelines, as well as providing excellent mobility during navigation. After carrying out analysis for fittings in pipelines, mathematical descriptions of their geometries are presented, which make it possible to estimate the movement patterns of the robot while passing through the fittings. Also, we propose a method of controlling the robot by modulating speeds of driving wheels that is applicable without sophisticated sensory information. To confirm the effectiveness of the proposed method, experiments are performed, and supplementary considerations on the design of the in-pipe robot are discussed.

  • Differential-Drive in-pipe robot for moving inside urban gas pipelines
    IEEE Transactions on Robotics, 2005
    Co-Authors: Segon Roh, Hyouk Ryeol Choi
    Abstract:

    Pipelines for the urban gas-supply system require a robot possessing outstanding mobility and advanced control algorithms, since they are configured with various pipeline elements, such as straight pipelines, elbows, and branches. We present a comprehensive work for moving inside underground urban gas pipelines with a miniature Differential-Drive in-pipe robot, called the Multifunctional Robot for IN-pipe inSPECTion (MRINSPECT) IV. MRINSPECT IV has been developed for the inspection of urban gas pipelines with a nominal 4-in inside diameter. The mechanism for steering with Differential-Drive wheels, arranged three-dimensionally, allows it to easily adapt to most of the existing configurations of pipelines, as well as providing excellent mobility during navigation. After carrying out analysis for fittings in pipelines, mathematical descriptions of their geometries are presented, which make it possible to estimate the movement patterns of the robot while passing through the fittings. Also, we propose a method of controlling the robot by modulating speeds of driving wheels that is applicable without sophisticated sensory information. To confirm the effectiveness of the proposed method, experiments are performed, and supplementary considerations on the design of the in-pipe robot are discussed.

Devin J. Balkcom - One of the best experts on this subject based on the ideXlab platform.

  • for Differential-Drive Mobile Robots
    2009
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    The shortest paths for a mobile robot are a fundamental property of the mechanism, and may also be used as a family of primitives for mo- tion planning in the presence of obstacles. This paper characterizes shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest, the total amount of wheel-rotation is optimized. Using the Pontrya- gin Maximum Principle and other tools, we derive the set of optimal paths, and we give a representation of the extremals in the form of finite automata. It turns out that minimum time for the Reeds-Shepp car is equal to minimum wheel-rotation for the Differential-Drive, and minimum time curves for the convexified Reeds-Shepp car are exactly the same as minimum wheel-rotation paths for the Differential-Drive. It is currently unknown whether there is a simpler proof for this fact. KEY WORDS—optimal control, nonholonomic constraints, shortest paths (or geodesics), Differential Drive, mobile robot

  • Minimum Wheel-Rotation Paths for Differential-Drive Mobile Robots
    The International Journal of Robotics Research, 2009
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    The shortest paths for a mobile robot are a fundamental property of the mechanism, and may also be used as a family of primitives for motion planning in the presence of obstacles. This paper characterizes shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest, the total amount of wheel-rotation is optimized. Using the Pontryagin Maximum Principle and other tools, we derive the set of optimal paths, and we give a representation of the extremals in the form of finite automata. It turns out that minimum time for the Reeds-Shepp car is equal to minimum wheel-rotation for the Differential-Drive, and minimum time curves for the convexified Reeds-Shepp car are exactly the same as minimum wheel-rotation paths for the Differential-Drive. It is currently unknown whether there is a simpler proof for this fact.

  • minimum wheel rotation paths for Differential Drive mobile robots
    International Conference on Robotics and Automation, 2006
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    Characterizing optimal paths for mobile robots is an interesting, important, and challenging endeavor. Not only they are interesting with respect to the optimized criteria, but also they offer a family of motion primitives that can be used for motion planning in the presence of obstacles. This paper presents characterization of shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest., the total amount of wheel rotation is optimized. Using Pontryagin maximum principle and other tools, we establish the existence of optimal trajectories, and derive the set of optimal paths. Some Reeds-Shepp curves appear in the set of optimal paths, whereas there are optimal paths which are different from Reeds-Shepp curves. To the best of our knowledge, this is the first progress on the problem

  • Time Optimal Trajectories for Bounded Velocity Differential Drive Vehicles
    The International Journal of Robotics Research, 2002
    Co-Authors: Devin J. Balkcom, Matthew T. Mason
    Abstract:

    This paper presents the time optimal trajectories for Differential Drive vehicles in the unobstructed plane. The wheel angular velocities are bounded, but may be discontinuous. The paper proves the existence of optimal controls, derives the structure of optimal trajectories, and develops an algorithm for producing a time optimal trajectory between any two configurations. Every nontrivial optimal trajectory is composed of straight segments alternating with turns about the robot's center. Optimal trajectories may have as many as five actions, but four actions are sufficient—for every optimal trajectory of five actions, there is an equally fast trajectory with four actions.

  • ICRA - Time optimal trajectories for bounded velocity Differential Drive robots
    Proceedings 2000 ICRA. Millennium Conference. IEEE International Conference on Robotics and Automation. Symposia Proceedings (Cat. No.00CH37065), 1
    Co-Authors: Devin J. Balkcom, Matthew T. Mason
    Abstract:

    A Differential Drive robot is perhaps the simplest type of mobile robot, and the bounded velocity model is perhaps the simplest useful model of the admissible controls. This paper develops the bounded velocity model for Differential Drive mobile robots, and derives the time-optimal trajectories.

Hamidreza Chitsaz - One of the best experts on this subject based on the ideXlab platform.

  • for Differential-Drive Mobile Robots
    2009
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    The shortest paths for a mobile robot are a fundamental property of the mechanism, and may also be used as a family of primitives for mo- tion planning in the presence of obstacles. This paper characterizes shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest, the total amount of wheel-rotation is optimized. Using the Pontrya- gin Maximum Principle and other tools, we derive the set of optimal paths, and we give a representation of the extremals in the form of finite automata. It turns out that minimum time for the Reeds-Shepp car is equal to minimum wheel-rotation for the Differential-Drive, and minimum time curves for the convexified Reeds-Shepp car are exactly the same as minimum wheel-rotation paths for the Differential-Drive. It is currently unknown whether there is a simpler proof for this fact. KEY WORDS—optimal control, nonholonomic constraints, shortest paths (or geodesics), Differential Drive, mobile robot

  • Minimum Wheel-Rotation Paths for Differential-Drive Mobile Robots
    The International Journal of Robotics Research, 2009
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    The shortest paths for a mobile robot are a fundamental property of the mechanism, and may also be used as a family of primitives for motion planning in the presence of obstacles. This paper characterizes shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest, the total amount of wheel-rotation is optimized. Using the Pontryagin Maximum Principle and other tools, we derive the set of optimal paths, and we give a representation of the extremals in the form of finite automata. It turns out that minimum time for the Reeds-Shepp car is equal to minimum wheel-rotation for the Differential-Drive, and minimum time curves for the convexified Reeds-Shepp car are exactly the same as minimum wheel-rotation paths for the Differential-Drive. It is currently unknown whether there is a simpler proof for this fact.

  • ICRA - Minimum Wheel-Rotation Paths for Differential Drive Mobile Robots Among Piecewise Smooth Obstacles
    Proceedings 2007 IEEE International Conference on Robotics and Automation, 2007
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle
    Abstract:

    Computing optimal paths for mobile robots is an interesting and important problem. This paper presents a method to compute the shortest path for a Differential-Drive mobile robot, which is a disc, among piecewise smooth and convex obstacles. To obtain a well-defined notion of shortest, the total amount of wheel rotation is optimized. We use recent characterization of minimum wheel-rotation paths for Differential-Drive mobile robots with no obstacles. We reduce the search for the shortest path to the search on a finite nonholonomic visibility graph. Edges of the graph are either minimum wheel-rotation trajectories inside the free space or trajectories on the boundary of obstacle region. Vertices of the graph are initial and goal configurations and points on the boundary of obstacle region. We call the search graph a nonholonomic visibility graph because the jump condition of the Pontryagin maximum principle gives a necessary condition which is reminiscent of bitangency in well-known visibility graphs. To the best of our knowledge, this is the first progress on the problem

  • minimum wheel rotation paths for Differential Drive mobile robots
    International Conference on Robotics and Automation, 2006
    Co-Authors: Hamidreza Chitsaz, Steven M. Lavalle, Devin J. Balkcom, Matthew T. Mason
    Abstract:

    Characterizing optimal paths for mobile robots is an interesting, important, and challenging endeavor. Not only they are interesting with respect to the optimized criteria, but also they offer a family of motion primitives that can be used for motion planning in the presence of obstacles. This paper presents characterization of shortest paths for Differential-Drive mobile robots, with the goal of classifying solutions in the spirit of Dubins curves and Reeds-Shepp curves for car-like robots. To obtain a well-defined notion of shortest., the total amount of wheel rotation is optimized. Using Pontryagin maximum principle and other tools, we establish the existence of optimal trajectories, and derive the set of optimal paths. Some Reeds-Shepp curves appear in the set of optimal paths, whereas there are optimal paths which are different from Reeds-Shepp curves. To the best of our knowledge, this is the first progress on the problem