29,685 research outputs found

    Autonomous Parallel Parking of a Car-Like Mobile Robot with Geometric Path Planning

    Get PDF
    With the advancement of technology making everything so convenient in these days and ages, autonomous system is very interesting area in the innovating technology. One of the advanced booming technologies for the improvement of human race is autonomous taxi mobile transportation system. It is working well in a district area but it still thrives on making more comfortable. This research will be one point of supporting roles for automobile in parallel parking. An autonomous parallel parking of a car-like mobile robot has been developed in this study. The ultrasonic range sensors are used to detect the working environments and design an s-shaped trajectory between two parallel parked vehicles. One trail maneuver system is used to be moving along the s-shaped trajectory parking path. The s-shaped trajectory is purely based on the geometric approach path planning method. The proposed method is not dependent on the initial pose of the robot but it must be parallel with the parking space. Sensor data are used as the main decision part to change the parking states instance of to find the parking space and adjust robot orientation. Fuzzy filter is applied to stabilize the sensor data and give a quick response input. The working environment is constrained by the wall and sensor arrangement. Visual studio 2013 is used for the user interface window. The effectiveness of the proposed method is demonstrated through some experimental results with a car-like mobile robot

    A layered fuzzy logic controller for nonholonomic car-like robot

    Get PDF
    A system for real time navigation of a nonholonomic car-like robot in a dynamic environment consists of two layers is described: a Sugeno-type fuzzy motion planner; and a modified proportional navigation based fuzzy controller. The system philosophy is inspired by human routing when moving between obstacles based on visual information including right and left views to identify the next step to the goal. A Sugeno-type fuzzy motion planner of four inputs one output is introduced to give a clear direction to the robot controller. The second stage is a modified proportional navigation based fuzzy controller based on the proportional navigation guidance law and able to optimize the robot's behavior in real time, i.e. to avoid stationary and moving obstacles in its local environment obeying kinematics constraints. The system has an intelligent combination of two behaviors to cope with obstacle avoidance as well as approaching a target using a proportional navigation path. The system was simulated and tested on different environments with various obstacle distributions. The simulation reveals that the system gives good results for various simple environments

    Nonholonomic motion planning: steering using sinusoids

    Get PDF
    Methods for steering systems with nonholonomic constraints between arbitrary configurations are investigated. Suboptimal trajectories are derived for systems that are not in canonical form. Systems in which it takes more than one level of bracketing to achieve controllability are considered. The trajectories use sinusoids at integrally related frequencies to achieve motion at a given bracketing level. A class of systems that can be steered using sinusoids (claimed systems) is defined. Conditions under which a class of two-input systems can be converted into this form are given

    Trajectory generation for the N-trailer problem using Goursat normal form

    Get PDF
    Develops the machinery of exterior differential forms, more particularly the Goursat normal form for a Pfaffian system, for solving nonholonomic motion planning problems, i.e., motion planning for systems with nonintegrable velocity constraints. The authors use this technique to solve the problem of steering a mobile robot with n trailers. The authors present an algorithm for finding a family of transformations which will convert the system of rolling constraints on the wheels of the robot with n trailers into the Goursat canonical form. Two of these transformations are studied in detail. The Goursat normal form for exterior differential systems is dual to the so-called chained-form for vector fields that has been studied previously. Consequently, the authors are able to give the state feedback law and change of coordinates to convert the N-trailer system into chained-form. Three methods for planning trajectories for chained-form systems using sinusoids, piecewise constants, and polynomials as inputs are presented. The motion planning strategy is therefore to first convert the N-trailer system into Goursat form, use this to find the chained-form coordinates, plan a path for the corresponding chained-form system, and then transform the resulting trajectory back into the original coordinates. Simulations and frames of movie animations of the N-trailer system for parallel parking and backing into a loading dock using this strategy are included

    Path planning for simple wheeled robots : sub-Riemannian and elastic curves on SE(2)

    Get PDF
    This paper presents a motion planning method for a simple wheeled robot in two cases: (i) where translational and rotational speeds are arbitrary and (ii) where the robot is constrained to move forwards at unit speed. The motions are generated by formulating a constrained optimal control problem on the Special Euclidean group SE(2). An application of Pontryagin’s maximum principle for arbitrary speeds yields an optimal Hamiltonian which is completely integrable in terms of Jacobi elliptic functions. In the unit speed case, the rotational velocity is described in terms of elliptic integrals and the expression for the position reduced to quadratures. Reachable sets are defined in the arbitrary speed case and a numerical plot of the time-limited reachable sets presented for the unit speed case. The resulting analytical functions for the position and orientation of the robot can be parametrically optimised to match prescribed target states within the reachable sets. The method is shown to be easily adapted to obstacle avoidance for static obstacles in a known environment
    corecore