Search results for "Mobile Robot"
showing 10 items of 71 documents
On-line adaptive neural network in very remote control system
2006
Remote control involves several issues that degrade seriously the performance of the plant to be controlled. This paper presents a strategy improving the characteristics of the remote control system, using an on-line adaptive neural net, in order to learn the variations of the remote system parameters to minimize the errors. This strategy is successfully applied to a client-server remote control system for a two link robot arm. Tests show that an error position in a remote control brushless motor can be highly reduced since its first "reference command" using a prevision of that error to modify the original reference. The neural net, used only by the client, is previously trained using loca…
A Rough-Terrain Casting Robot for the ESA Lunar Robotics Challenge
2009
This paper describes the design and implementation of DAVID, a lunar vehicle developed for the European Space Agency (ESA) Lunar Robotics Challenge, presenting severe terrain negotiation and sample acquisition challenges. We discuss in some detail two of the main innovative aspects of our entry to the challenge, i.e. the locomotion system and the sample acquisition system. Motivated by the challenge specifications, a range of different locomotion systems were considered, among which we chose a simple, rugged and effective wheeled system. We provide an account of the choice of five different types of wheels, which were designed, analyzed and experimentally tested in conditions similar to the…
Evaluation of automatically steered agricultural vehicles
2008
The popularization of automatic guidance systems for off-road vehicles, especially in agricultural environments, has led to a sudden affluence of commercial solutions. As a consequence, end users are often overwhelmed by the spread of possibilities commercially available, on top of the confusion provoked by the guidance accuracy advertised by manufacturers. Therefore, there is a need for a methodology that objectively quantifies the level of performance of any auto-steering system, classifying different solutions according to their accuracy and reliability. This paper describes a method to evaluate the behavior of any automatically driven agricultural vehicle traveling along paths of any cu…
VISOCAR: an autonomous industrial transport vehicle guided by visual navigation
2003
The authors describe a vision system, called VISOCAR, for mobile robot guidance in industrial environments. VISOCAR is an optically navigating AGV (automatically guided vehicle) that, owing to its local intelligence, can travel automatically in its natural environment, does not need any dedicated floor installations, and does not impose any restrictions on the route network or factory environment. It can navigate accurately on its track and integrate multisensor information to enhance functional redundancy and system reliability. It is shown that the navigation task can be broken down into a hierarchy of goals, which can be attained by functionally independent modules. The system architectu…
A mobile robot for vigilance tasks improved with a new robust and low cost communications system immune to attacks with EMI noise
2006
This work pretends to develop a robot for vigilance tasks that are able to tolerate diverse kinds of attacks and be able to operate in environments with elevated electromagnetic noise, being even immune to sabotage provoked by means of high electromagnetic fields. A new CAN based communications system that interconnects the different devices that compose the mobile robot has been developed to achieve this goal. The system is based on a shielded communications hub, that interconnects diverse nodes by means of CAN. On the other hand, the point to point communication between each node and the hub is carried out by means of economic optical fiber. With this approach all robot devices are connec…
A distributed architecture for autonomous navigation of robots
2002
The paper shows a distributed architecture for autonomous robot navigation. The architecture is based on three modules that are implemented on separate and interacting agents: the target recognizer, the obsta90cle evaluator and the planner. An adaptive genetic algorithm has been studied to identify mechanisms for reaching the target and for manipulating the 2-directions of the robot; the distributed architecture has been embedded in the DAISY (Distributed Architecture for Intelligent System). Experiments have been carried out using a LEGO intelligent brick.
Fuzzy Adaptive EKF Motion Control for Nonholonomic and Underactuated Cars with Parametric and non Parametric Uncertainties
2007
A new fuzzy adaptive motion control system including on-line extended Kalman''s filter (EKF) for wheeled underactuated cars with non-holonomic constraints on the motion is presented. The presence of parametric uncertainties in the kinematics and in the dynamics is treated using suitable differential adaptation laws. We merge adaptive control with fuzzy inference system. By using fuzzy system, the parameters of the kinematical controller are functions of the lateral, longitudinal and orientation errors of the motion. In this way we have a robust control system where the dynamics of the motion errors is with lower time response than the adaptive control without fuzzy. Also Lyapunov''s stabili…
Mobile Robot and Mobile Manipulator Research Towards ASTM Standards Development
2016
International audience; Performance standards for industrial mobile robots and mobile manipulators (robot arms onboard mobile robots) have only recently begun development. Low cost and standardized measurement techniques are needed to characterize system performance, compare different systems, and to determine if recalibration is required. This paper discusses work at the National Institute of Standards and Technology (NIST) and within the ASTM Committee F45 on Driverless Automatic Guided Industrial Vehicles. This includes standards for both terminology, F45.91, and for navigation performance test methods, F45.02. The paper defines terms that are being considered. Additionally, the paper de…
Local Monitor Implementation for Decentralized Intrusion Detection in Secure Multi–Agent Systems
2007
This paper focuses on the detection of misbehav- ing agents within a group of mobile robots. A novel approach to automatically synthesize a decentralized Intrusion Detection System (IDS) as well as an efficient implementation of local monitors are presented. In our scenario, agents perform possi- bly different independent tasks, but cooperate to guarantee the entire system’s safety. Indeed, agents plan their next actions by following a set of logic rules which is shared among them. Such rules are decentralized, i.e. they depend only on configurations of neighboring agents. However, some agents may not be acting according to this cooperation protocol, due to spontaneous failure or tampering.…
Fuzzy Data Fusion for Real-World Mapping Using 360° Rotating Ultrasonic Sensor
1997
Abstract Mobile robot perception of the external environment is limited by the features of the used sensor. An useful technique used to improve robot perception is data fusion. This paper presents an approach to build a map of an unknown environment applying fuzzy data fusion methods to data acquired through an ultrasonic sensor. Conditioning of these data and motion control of the mobil robot by fuzzy data fusion are also described. The resulting two dimensional map is used for path planning and navigation. The proposed approach is exrperimentally tested using real distance measures acquired by a 360° rotating sensor.