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.

A Floor and Obstacle Height Map for 3D Navigation of a Humanoid Robot

Abstract: With the development of biped robots, systems became able to navigate in a 3 dimensional world, walking up and down stairs, or climbing over small obstacles. We present a method for obtaining a labeled 2.5D grid map of the robot's surroundings. Each cell is marked either as floor or obstacle and contains a value telling the height of the floor or obstacle. Such height maps are useful for path planning and collision avoidance. The method uses a novel combination of a 3D occupancy grid for robust sensor data interpretation and a 2.5D height map for fine resolution floor values. We evaluate our approach using stereo vision on the humanoid robot QRIO and show the advantages over previous methods. Experimental results from navigation runs on an obstacle course demonstrate the ability of the method to generate detailed maps for autonomous navigation.

Optimal layout design of obstacles for panic evacuation using differential evolution

Abstract: To improve the pedestrian outflow in panic situations by suitably placing an obstacle in front of the exit, it is vital to understand the physical mechanism behind the evacuation efficiency enhancement. In this paper, a robust differential evolution is firstly employed to optimize the geometrical parameters of different shaped obstacles in order to achieve an optimal evacuation efficiency. Moreover, it is found that all the geometrical parameters of obstacles could markedly influence the evacuation efficiency of pedestrians, and the best way for achieving an optimal pedestrian outflow is to slightly shift the obstacle from the center of the exit which is consistent with findings of extant literature. Most importantly, by analyzing the profiles of density, velocity and specific flow, as well as the spatial distribution of crowd pressure, we have proven that placing an obstacle in panic situations does not reduce or absorb the pressure in the region of exit, on the contrary, promotes the pressure to a much higher level, hence the physical mechanism behind the evacuation efficiency enhancement is not a pressure decrease in the region of exit, but a significant reduction of high density region by effective separation in space which finally causes the increasing of escape speed and evacuation outflow. Finally, it is clearly demonstrated that the panel-like obstacle is considerably more robust and stable than the pillar-like obstacle to guarantee the enhancement of evacuation efficiency under different initial pedestrian distributions, different initial crowd densities as well as different desired velocities.

Remote control for a parking assistance system and a parking assistance system which can be controlled by remote control

Abstract: One aspect of the invention relates to a remote control for a parking assistance system which can be controlled by remote control and has the purpose of automatically parking a passenger car in a parking space. The system is preferably a parking assistance system for frontal parking in a head parking space (for example an individual garage). The parking assistance system comprises a surroundings sensor system with supplies sensor information. Furthermore, an obstacle detection device is provided for detecting the presence of an obstacle on the basis of the sensor information from the surroundings sensor system. In addition, a bidirectional communication device is present. The latter transmits obstacle detection information, determined by means of the obstacle detection device, relating to the presence of an obstacle to the remote control. The remote control comprises a bidirectional communication device for wireless communication with the passenger car. In addition, one or more parking function operator controls are provided for controlling the parking in the space and/or exiting from the space. The bidirectional communication device is configured to receive obstacle detection information which is determined by means of the obstacle detection device. In addition, the remote control comprises signalling means for signalling the presence of an obstacle to the operator of the remote control as a function of the obstacle detection information.

Real-time obstacle detection using stereo vision for autonomous ground vehicles: A survey

Abstract: One of the most important features for any intelligent ground vehicle is based on how is reliable and complete the perception of the environment and the capability to discriminate what an obstacle is. Obstacle Detection (OD) is one of the most widely discussed topics in literature. Many approaches have been presented for different application fields and scenarios; in last years most of them have been revisited using stereo vision or 2D/3D sensor technologies. In this paper we present a brief survey about Obstacle Detection techniques based on stereo vision for intelligent ground vehicles, describing and comparing the most interesting approaches. In order to provide a generic overview of these techniques, it has been decided to focus the study only on the algorithms that have provided a major contribution through real-time experiments in unsupervised scenarios.

Stochastic performance, modeling and evaluation of obstacle detectability with imaging range sensors

Abstract: Statistical modeling and evaluation of the performance of obstacle detection systems for unmanned ground vehicles (UGV's) is essential for the design, evaluation and comparison of sensor systems. In this report, we address this issue for imaging range sensors by dividing the evaluation problem into two levels: quality of the range data itself and quality of the obstacle detection algorithms applied to the range data. We review existing models of the quality of range data from stereo vision and AM-CW LADAR, then use these to derive a new model for the quality of a simple obstacle detection algorithm. This model predicts the probability of detecting obstacles and the probability of false alarms, as a function of the size and distance of the obstacle, the resolution of the sensor, and the level of noise in the range data. We evaluate these models experimentally using range data from stereo image pairs of a gravel road with known obstacles at several distances. The results show that the approach is a promising tool for predicting and evaluating the performance of obstacle detection with imaging range. >