scholarly journals The Ariadne's Clew Algorithm

1998 ◽  
Vol 9 ◽  
pp. 295-316 ◽  
Author(s):  
E. Mazer ◽  
J. M. Ahuactzin ◽  
P. Bessiere
Keyword(s):  
Path Planning ◽  
Degrees Of Freedom ◽  
Optimization Problems ◽  
Dynamic Environment ◽  
Dynamic Environments ◽  
Experimental Results ◽  
High Dimensional ◽  
New Approach ◽  
Six Degrees Of Freedom ◽  
Moving Obstacle

We present a new approach to path planning, called the ``Ariadne's clew algorithm''. It is designed to find paths in high-dimensional continuous spaces and applies to robots with many degrees of freedom in static, as well as dynamic environments --- ones where obstacles may move. The Ariadne's clew algorithm comprises two sub-algorithms, called SEARCH and EXPLORE, applied in an interleaved manner. EXPLORE builds a representation of the accessible space while SEARCH looks for the target. Both are posed as optimization problems. We describe a real implementation of the algorithm to plan paths for a six degrees of freedom arm in a dynamic environment where another six degrees of freedom arm is used as a moving obstacle. Experimental results show that a path is found in about one second without any pre-processing.

Offline decoupled path planning approach for effective coordination of multiple robots

Robotica ◽  
2009 ◽  
Vol 28 (4) ◽  
pp. 477-491 ◽  
Author(s):  
Shital S. Chiddarwar ◽  
N. Ramesh Babu
Keyword(s):  
Path Planning ◽  
Free Path ◽  
Minimum Distance ◽  
Degrees Of Freedom ◽  
Multiple Robots ◽  
A Algorithm ◽  
Two Phase ◽  
Six Degrees Of Freedom ◽  
Planning Approach ◽  
End Effectors

SUMMARYIn this paper, a decoupled offline path planning approach for determining the collision-free path of end effectors of multiple robots involved in coordinated manipulation is proposed. The proposed approach for decoupled path planning is a two-phase approach in which the path for coordinated manipulation is generated with a coupled interaction between collision checking and path planning techniques. Collision checking is done by modelling the links and environment of robot using swept sphere volume technique and utilizing minimum distance heuristic for interference check. While determining the path of the end effector of robots involved in coordinated manipulation, the obstacles present in the workspace are considered as static obstacles and the links of the robots are viewed as dynamic obstacles by the other robot. Coordination is done in offline mode by implementing replanning strategy which adopts incremental A* algorithm for searching the collision-free path. The effectiveness of proposed decoupled approach is demonstrated by considering two examples having multiple six degrees of freedom robots operating in 3D work cell environment with certain static obstacles.

General Mathematical Model of Multi-Arm Cooperating Robots With Elastic Interconnection at the Contact

1997 ◽  
Vol 119 (4) ◽  
pp. 707-717 ◽  
Author(s):  
Milovan Z˘ivanovic´ ◽  
Miomir Vukobratovic´
Keyword(s):  
Mathematical Model ◽  
Degrees Of Freedom ◽  
Dynamic Environment ◽  
Six Degrees Of Freedom ◽  
General Mathematical Model ◽  
Cooperating Robots ◽  
Six Degree Of Freedom ◽  
Physical Phenomena ◽  
First Time ◽  
Object Dynamic

The procedure of modeling and the complete general form mathematical model of manipulators with six degrees of freedom in cooperative work are presented in the paper, together with the solution of undefiniteness problem with respect to force distribution. For the first time, a system of active spatial six-degree-of-freedom mechanisms elastically interconnected with the object (dynamic environment) is modeled. The reason for the emergence of the undefiniteness problem with respect to force is explained and the procedure for solving this problem given. Unlike the approaches given in the available literature, the undefiniteness problem with respect to force is solved in accordance with physical phenomena. The modeling procedure is illustrated by a simplified example.

A Parallel Six Degrees-of-Freedom Inflatable Robot

2000 ◽  
Author(s):  
Patricia Ben-Horin (Dombiak) ◽  
Moshe Shoham ◽  
Gershon Grossman
Keyword(s):  
Path Planning ◽  
Degrees Of Freedom ◽  
Parallel Robot ◽  
Six Degrees Of Freedom ◽  
Robot Architecture

Abstract A new structure of a six degrees-of-freedom robot is described in this paper. The robot presents two new features: three inflatable links that constitute the robot structure and parallel robot architecture with large workspace. These features result in a lightweight and easy to deploy robot. The structure, kinematics and path planning of the experimental robot are presented.

scholarly journals Robot Path Planning using Dynamic Programming with Accelerating Nodes

2012 ◽  
Vol 3 (1) ◽  
Author(s):  
Rahul Kala ◽  
Anupam Shukla ◽  
Ritu Tiwari
Keyword(s):  
Dynamic Programming ◽  
Path Planning ◽  
Real Time ◽  
Dynamic Environments ◽  
Experimental Results ◽  
Robot Path Planning ◽  
Optimal Paths ◽  
Additional Processing ◽  
Update Frequency ◽  
Robot Path

AbstractWe solve the problem of robot path planning using Dynamic Programming (DP) designed to perform well in case of a sudden path blockage. A conventional DP algorithm works well for real time scenarios only when the update frequency is high i.e. changes can be readily propagated. In case updates are costly, for a sudden blockage the robot continues moving along the wrong path or stands stationary. We propose a modified DP that has nodes with additional processing (called accelerating nodes) to enable different segments of the map to become informed about the blockage rapidly. We further quickly compute an alternative path in case of a blockage. Experimental results verify that usage of accelerating nodes makes the robot follow optimal paths in dynamic environments.

scholarly journals Design and Development of a Littoral AUV for Underwater Target Localization and Homing Using Vision and SONAR Module

ISRN Robotics ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
R. K. Sinha ◽  
Aayush Jha ◽  
Faheem Ahmad ◽  
Vivek Mishra ◽  
Prateek Murgai ◽  
...  
Keyword(s):  
Power Systems ◽  
Degrees Of Freedom ◽  
Autonomous Underwater Vehicle ◽  
Mechanical Design ◽  
Water Environment ◽  
Experimental Results ◽  
Design And Development ◽  
Sound Sources ◽  
Six Degrees Of Freedom ◽  
Underwater Target

This paper presents the design and development of a modular littoral autonomous underwater vehicle called “ZYRA” having six degrees of freedom for performing the following tasks underwater: target (sound sources emitting frequencies between 1 Hz and 180 KHz) localization and homing, buoy detection. The development of the AUV has been divided into, namely, five sections: mechanical design and fabrication, embedded and power systems, control and software, image processing, and underwater acoustics. A fully functional AUV has been tested in a self-created arena with different tasks spread out in a shallow water environment. Two different kinds of experimental results have been presented: first the experimental results of the SONAR module and second based on the number of successful outcomes per total number of trials for each task.

Kinematic analysis and path planning of a new kinematically redundant planar parallel manipulator

Robotica ◽  
2008 ◽  
Vol 26 (3) ◽  
pp. 405-413 ◽  
Author(s):  
Iman Ebrahimi ◽  
Juan A. Carretero ◽  
Roger Boudreau
Keyword(s):  
Path Planning ◽  
Condition Number ◽  
Kinematic Analysis ◽  
Parallel Manipulator ◽  
Degrees Of Freedom ◽  
Six Degrees Of Freedom ◽  
Displacement Problem ◽  
Singular Configurations ◽  
Planar Parallel Manipulator

SUMMARYIn this work, the 3-RPRR, a new kinematically redundant planar parallel manipulator with six-degrees-of-freedom, is presented. First, the manipulator is introduced and its inverse displacement problem discussed. Then, all types of singularities of the 3-RPRR manipulator are analysed and demonstrated. Thereafter, the dexterous workspace is geometrically obtained and compared with the non-redundant 3-PRR planar parallel manipulator. Finally, based on a geometrical measure of proximity to singular configurations and the condition number of the manipulators' Jacobian matrices, actuation schemes for the manipulators are obtained. Different actuation schemes for a given path are obtained and the quality of their actuation schemes are compared. It is shown that the proposed manipulator is capable of following a path while avoiding the singularities.

An Optimization Approach Toward a Robust Design of Six Degrees of Freedom Haptic Devices

2015 ◽  
Vol 137 (4) ◽  
Author(s):  
Aftab Ahmad ◽  
Kjell Andersson ◽  
Ulf Sellgren
Keyword(s):  
Design Optimization ◽  
Robust Design ◽  
Degrees Of Freedom ◽  
Design Parameters ◽  
Manufacturing Cost ◽  
Optimization Approach ◽  
Performance Indices ◽  
New Approach ◽  
Haptic Devices ◽  
Six Degrees Of Freedom

This work presents an optimization approach for the robust design of six degrees of freedom (DOF) haptic devices. Our objective is to find the optimal values for a set of design parameters that maximize the kinematic, dynamic, and kinetostatic performances of a 6-DOF haptic device while minimizing its sensitivity to variations in manufacturing tolerances. Because performance indices differ in magnitude, the formulation of an objective function for multicriteria performance requirements is complex. A new approach based on Monte Carlo simulation (MCS) was used to find the extreme values (minimum and maximum) of the performance indices to enable normalization of these indices. The optimization approach presented here is formulated as a methodology in which a hybrid design-optimization approach, combining genetic algorithm (GA) and MCS, is first used. This new approach can find the numerical values of the design parameters that are both optimal and robust (i.e., less sensitive to variation and thus to uncertainties in the design parameters). In the following step, with design optimization, a set of optimum tolerances is determined that minimizes manufacturing cost and also satisfies the allowed variations in the performance indices. The presented approach can thus enable the designer to evaluate trade-offs between allowed performance variations and tolerances cost.

Path Planning for Mobile Robots in 3D Dynamic Environments

2011 ◽  
Vol 403-408 ◽  
pp. 1401-1404
Author(s):  
Li Jia Chen ◽  
He Jin ◽  
Jin Ke Bai ◽  
Hai Tao Mao
Keyword(s):  
Path Planning ◽  
Mobile Robots ◽  
Dynamic Environment ◽  
Dynamic Environments ◽  
Artificial Potential Field ◽  
Uniform Motion ◽  
Breadth First Search ◽  
Time Step ◽  
Planning Algorithm ◽  
Path Planning Algorithm

Aiming at the robustness of the path planning of mobile robots in the 3D dynamic environment, an improved ARF (Artificial Potential Field) based path planning algorithm is proposed in this paper. Supposing that all the obstacles move regularly and the robot is on uniform motion in a grid 3D environment. Firstly, the algorithm computes the future statuses of the environment, such as the coordinate of all the obstacles and the goal, until a time step T in which there is at least one route between the start and goal. T is obtained by BFS (Breadth First Search) and environment configuration parameters. Secondly, because in every time step the environment can be consider as being static, ARF is used to determine the potential value of every space position in each time step. Finally, a route along the lowest potential values is found for the robot from the start to goal. Simulation results show that the algorithm makes the robot avoid obstacles effectively and reach the goal safely.

Cooperative Obstacle Avoidance of Multiple Robotic Fishes Based on Grids Method

2014 ◽  
Vol 536-537 ◽  
pp. 929-933
Author(s):  
Yu Lian Jiang
Keyword(s):  
Genetic Algorithm ◽  
Path Planning ◽  
Obstacle Avoidance ◽  
Optimal Path ◽  
Experimental Results ◽  
New Method ◽  
Local Minima ◽  
New Approach ◽  
Serial Number

To resolve the problem of obstacle avoidance and path planning of multiple robotic fishes, this paper proposes a new approach which uses collaboration mechanism based on grids method. The proposed approach splits the workspace of those robotic fishes using grids method, identifies each grid with serial number, designs the cooperative mechanism to avoid collision among these fishes, and plans the path for each fish. This method was applied in the obstacle avoidance competition of multiple robotic fishes which happening in a field with obstacle in it. The experimental results show the new method is more effective, can get more optimal path, and avoid the local minima issue which arises frequently in the A-star algorithm and genetic algorithm. It significantly improves the ability of the multiple robotic fishes system on the aspect of path planning and coordination.

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