Obstacle

About: Obstacle is a research topic. Over the lifetime, 9517 publications have been published within this topic receiving 94760 citations. The topic is also known as: impediment & barrier.

Method and system for forward collision avoidance in an automotive vehicle

Abstract: The present patent application relates to a method and system for autonomous action in multiple obstacle scenarios in an automotive vehicle forward collision avoidance system. Initially the presence of obstacles in front of a vehicle hosting the system is established. Thereafter the position, velocity and acceleration of the obstacles are estimated. The maneuvers which the vehicle is capable of performing that will lead to a collision with each respective obstacle is evaluated separately. The union of maneuvers which will lead to collision with any one of the obstacles is formed. The set of maneuvers which the vehicle is capable of performing through which collision with any of the obstacles may be avoided is established, and the set used for deciding how to avoid or mitigate collision with any one of the obstacles. Finally a collision avoidance maneuver based on said decision is executed autonomously.

Numerical solutions of third-order obstacle problems

Abstract: It is known that a class of odd order obstacle problems in physical oceanography can be studied in the framework of variational inequality theory. In this paper, we show that variational inequalities related with third-order obstacle problems can be characterized by a system of variational equations without constraints, which are solved using modified finite difference technique. A comparison between our and other available results is also presented.

Low Cost Obstacle Avoidance Robot

Abstract: This paper deals with a low cost solution to obstacle avoidance for a mobile robot. This paper also prese nts a dynamic steering algorithm which ensures that the robot does n't have to stop in front of an obstacle which allows robot to na vigate smoothly in an unknown environment, avoiding collisions. The obstacle avoidance strategy has been described. Obstacle avoidance strategy and working of robot is greatly d ependent on the detection of obstacles by sensors and correspon ding response of robot. Working principle of sensors, limitation of their use and obstacle avoidance algorithm has been discussed in detail.

Distributed Cooperative Avoidance Control for Multi-Unmanned Aerial Vehicles

Abstract: It is well-known that collision-free control is a crucial issue in the path planning of unmanned aerial vehicles (UAVs). In this paper, we explore the collision avoidance scheme in a multi-UAV system. The research is based on the concept of multi-UAV cooperation combined with information fusion. Utilizing the fused information, the velocity obstacle method is adopted to design a decentralized collision avoidance algorithm. Four case studies are presented for the demonstration of the effectiveness of the proposed method. The first two case studies are to verify if UAVs can avoid a static circular or polygonal shape obstacle. The third case is to verify if a UAV can handle a temporary communication failure. The fourth case is to verify if UAVs can avoid other moving UAVs and static obstacles. Finally, hardware-in-the-loop test is given to further illustrate the effectiveness of the proposed method.

Multi-obstacle path planning and optimization for mobile robot

Abstract: In the past few decades, many results have been achieved in the research of mobile robot path planning, and they have been applied in simple scenarios, such as factory AGV, bank guide robot. However, path planning in highly dense and complex scenarios has become an important challenge for applications. Robots face dense map and complex obstacles and hardly find out an optimal path within a reasonable period, such as unmanned vehicles in freight ports and rescue robots in earthquake environment. Therefore, a multi-obstacle path planning and optimization method is proposed. In order to simplify complex environmental obstacles, the obstacles will be divided into basis obstacles and extension obstacles. Firstly, the basis obstacles and their contour point sets are determined according to the starting point and goal point. Furthermore, the basis obstacles are optimized by convex hulls, and then the corresponding basis point set is obtained. Secondly, the extension obstacles are determined by the basis point set, starting point and goal point, and then the corresponding extension point set is generated. After that, a path planner is designed by the multi-objective D* Lite algorithm for distance and smoothness in order to get reasonable and optimized path in a complex environment. Moreover, the path is smoothed by cubic bezier curves to fit the kinematic model of the robot. Finally, The proposed method conduct comparative experiments with other algorithms to verify its accuracy and computational efficiency of planning in complex environments.