Search results for "Collision avoidance"
showing 10 items of 24 documents
A novel clustering-based algorithm for solving spatially-constrained robotic task sequencing problems
2021
The robotic task sequencing problem (RTSP) appears in various forms across many industrial applications and consists of developing an optimal sequence of motions to visit a set of target points defined in a task space. Developing solutions to problems involving complex spatial constraints remains challenging due to the existence of multiple inverse kinematic solutions and the requirements for collision avoidance. So far existing studies have been limited to relaxed RTSPs involving a small number of target points and relatively uncluttered environments. When extending existing methods to problems involving greater spatial constraints and large sets of target points, they either require subst…
A Novel Architecture for Inter-FPGA Traffic Collision Management
2014
International audience; —with the increasing complexity of various communi-cations and applications, Network-On-Chip (NoC) is one of the most efficient communication structures. Multi-FPGA platforms are considered as the most appropriate experimental solutions to emulate a large size of MPSoCs (Multi-Processor System-on-Chip) based on a NoC. The deployment of the NoC into several FPGAs requires the use of inter-FPGA communication links. The number and performance of external links restrict the bandwidth of communication. Currently, the number of inter-FPGA signals is considered as a substantial problem in NoC implemented on Multi-FPGA architectures. In this paper, we propose the integration…
A MOBILE ROBOT FOR TRANSPORT APPLICATIONS IN HOSPITAL DOMAIN WITH SAFE HUMAN DETECTION ALGORITHM
2009
We have been developing a MKR (Muratec Keio Robot), an autonomous omni-directional mobile transfer robot system for hospital applications. This robot has a wagon truck to transfer luggage, important specimens and other materials. This study proposes a safe obstacle collision avoidance technique that includes a human detection algorithm for omni directional mobile robots that realizes a safe movement technology. The robot can distinguish people from others obstacles with human detection algorithm. The robot evades to people more safely by considering its relative position and velocity with respect to them. Some experiments in a hospital were carried out to verify the performance of the human…
Connected and Autonomous Vehicles cooperate with the pedestrian in industrial sites based on trajectory optimization and vehicle signalization system
2020
Connected and autonomous vehicles (CAV) is the development trend in the field of transportation systems. Recent studies show that the resources sharing between pedestrians and CAV is a big challenge. Considering traffic safety and efficiency at that sharing point not only requires a collision avoidance system but also more communicative behaviors of the CAV. More precisely, pedestrian needs to understand the intention of the incoming CAV whether it will cross first or not according to its speed profile. This paper uses the optimal trajectory control to provide CAV with a communicative behavior. A scenario where CAV and pedestrian cooperate together to cross a conflict zone is studied. A com…
Real-time smoothing of car-following data through sensor-fusion techniques
2011
Abstract Observation of vehicles kinematics is an important task for many applications in ITS (Intelligent Transportation Systems). It is at the base of both theoretical analyses and application developments, especially in case of positioning and tracing/tracking of vehicles, car-following analyses and models, navigation and other ATIS (Advanced Traveller Information Systems), ACC (Adaptive Cruise Control) systems, CAS and CWS (Collision Avoidance Systems and Collision Warning Systems) and other ADAS (Advanced Driving Assistance Systems). Modern technologies supply low-cost devices able to collect time series of kinematic and positioning data with medium to very high frequency. Even more da…
Real-time human collision detection for industrial robot cells
2017
A collision detection system triggering on human motion was developed using the Robot Operating System (ROS) and the Point Cloud Library (PCL). ROS was used as the core of the programs and for the communication with an industrial robot. Combining the depths fields from the 3D cameras was accomplished by the use of PCL. The library was also the underlying tool for segmenting the human from the registrated point clouds. Benchmarking of several collision algorithms was done in order to compare the solution. The registration process gave satisfactory results when testing the repetitiveness and the accuracy of the implementation. The segmentation algorithm was able to segment a person represente…
Collision Avoidance Trajectory for an Ekranoplan.
2009
The risk of collision is one of the crucial aspects for the applications of Ekranoplans in civil transportation. In fact, the extremely low flight altitude of these aircraft increases dramatically the chances of interference between their flight path and the multitude of obstacles populating the surrounding area. In this work we consider the optimal collision avoidance problem between a cruising Ekranoplan and a steady obstacle located on its flight path. First we solve the optimal control problem imposing that the collision avoidance maneuver lies on the longitudinal plane identified by the initial cruising conditions. In the second part of this work we state the three-dimensional version …
MAC Protocols for WuR Enabled WSNs : Design and Performance Evaluation
2017
Master's thesis Information- and communication technology IKT591 - University of Agder 2017 Increasing energy efficiency is a challenging task for protocol design in wireless sensor networks (WSNs) as well as in Internet of things (IoT). Traditionally, duty-cycled (DC) protocols have been widely adopted for data transmissions in WSNs for energy conservation by reducing idle listening and overhearing. Recently, wake-up radio (WuR) has merged as a promising technique to replace DC protocols thanks to its superior performance in both network lifetime and transmission latency. This thesis work focuses on the design and performance evaluation of WuR-enabled MAC protocols considering various traf…
Adaptive Collision Avoidance through Implicit Acknowledgments in WSNs
2008
The large number of nodes, typical of many sensor network deployments, and the well-known hidden terminal problem make collision avoidance an essential goal for the actual employment of WSN technology. Collision avoidance is traditionally dealt with at the MAC Layer and plenty of different solutions have been proposed, which however have encountered limited diffusion because of their incompatibility with commonly available devices.In this paper we propose an approach to collision avoidance which is designed to work over a standard MAC Layer, namely the IEEE 802.15.4 MAC, and is based on application-controlled delays of packet transmission times. The proposed scheme is simple, decentralized …