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This paper presents a platform to implement and evaluate a learning by imitation framework which enables humanoid robots to learn hand gestures from human beings. A marker based system is used to capture human motion data. From this data we extract the shoulder and elbow joint angles, which uniquely characterize a particular hand gesture. The proposed imitation learning framework aims to generalize...
In this paper, we describe a coordination framework for weakly centralized mobile robot teams in which the leader is not specified a priori, but it is selected dynamically during the mission depending on the task and the environment. The key to our approach is the integration of both centralized and decentralized coordination strategies at the individual robot level. Each robot relies on the local...
Haptic guidance has been investigated with force feedback for a long time. However, the equipment is expensive and affects the users' action. In this study, we use the vibration with motor to present user tactile feedback instead of force feedback. There are several different positions, inside the tunnel, outside of the tunnel and at the boundaries of tunnel, where designer can supply tactile feedback...
Crustal movement modeling and analysis are the major task in the earth system science. In this paper, a distributed system for simulating the crustal movement was developed with embedded systems and common programming languages. The crustal movement simulation system (CMSS) is designed based on multi-agent system (MAS). A three layered MAS architecture with good generality is presented, which can...
This paper treats the chaos synchronization problem of chaotic Chua circuit system. Based on LaSalle invariance principal, the proposed controller is featured that (a) only single variable information of the master system is needed; (b) the control law is a simple linear controller with low gain. Finally, the effectiveness of the proposed control law is also illustrated by the numerical simulation...
As the precondition to perform many tasks including person following and dynamic obstacle avoiding, object tracking is very important for mobile robot systems especially in populated dynamic environment. A novel hybrid conditional random field model which has a hierarchical structure and includes hidden states is proposed for multi-object tracking with a mobile platform. Since conditional random field...
The paper introduces a new air flow analysis approach based on Particle Tracking Velocimetry (PTV). One of the special features of the proposed method is that after the tracer particles are detected, matching and tracing are conducted jointly. To this end, we introduce an interpretation module based on a directed hypergraph for 3D curve reconstruction. At first the 2D inter-frame locations are localised...
As an important kind of non-stationary signals, the linear frequency modulation signals have been widely used in underwater acoustic communication systems and signal detection systems. The fractional Fourier transform is an effective transform manner to analyse non-stationary signals especially to detect linear frequency modulation signals. The time measurement manner can be changed into frequency...
Nonholonomic wheeled mobile robot's posture error model denoted by Cartesian coordinates in local coordinates is established. A novel nonlinear state feedback trajectory tracking control law is proposed, which causes closed-loop system state space equation of robot to have isolated equilibrium state at origin. Through analysing the local uniform asymptotical stability at origin and the instability...
A hybrid control algorithm is proposed based on a backstepping kinematic control and a PID sliding mode dynamic control with an adaptive neural network adjust gain of sliding mode control for trajectory tracking control of nonholonomic mobile robot. Parameters and non-parameter uncertainties of mobile robot can be solved by using the robust control which takes advantages of stability and robustness...
This paper focuses on a critical component of the situational awareness, the control of autonomous vertical flight for an unmanned aerial vehicle. Autonomous vertical flight is a challenging but important task for tactical unmanned aerial vehicles to achieve high level of autonomy under adverse conditions. With the situational awareness strategy, we proposed a two stage flight control procedure using...
Fault tolerance for a class of non linear systems is addressed based on the velocity of their output variables. This paper presents a mapping to minimize the possible jump of the velocity of the output, due to the actuator failure. The failure of the actuator is assumed as actuator lock. The mapping is derived and it provides the proper input commands for the healthy actuators of the system to tolerate...
During the processing of wafer, in order to avoid the friction between wafer and wafer box, and to guarantee the clean state of the working environment simultaneously, small contour error and little vibration are required for wafer transfer robot to deliver wafer, i.e., to achieve stable and accurate trajectory for wafer delivery. To lessen contour error, suppress vibration, a kind of control algorithm...
This paper presents a nonlinear input-state feedback linearization controller for tracking trajectory on horizontal plane with the rudder of an unmanned underwater vehicle (UUV). UUV system is strongly nonlinear, but the model is often simplified into linearization under some strict assumptions in some traditional linear control methods for the need of the control laws, and the linearization may induce...
Most existing localization algorithms use Mobile Beacon (MB) to broadcast beacon packets with its own coordinates for localizing unknown nodes. These algorithms do not need too much cost but obtain higher localization precision according to the mobile trajectory. In the case trajectory study of MB is the fundamental problem to be solved. In this paper, we propose a new static trajectory, k-coverage...
Iterative Learning control (ILC) is a powerful control concept that iteratively improves the behaviors of processes that are repetitive in nature. A new and systematic design of the PD iterative learning control has been presented based upon frequency domain of plant. For design specifications, including the convergence margin and cut-off frequency which is determined by useful input signal, a proper...
In this paper, an optimal design method is proposed to determine the PID coefficients for control discrete-time SISO LTI systems in order to improve the transient tracking performance. We analyzed the convergence of the scheme and its convergence condition is obtained in terms of the PID coefficients. Based on the model of a DC Motor, an illustrative example is given to demonstrate the effectiveness...
Action recognition is an important research issue in intelligent surveillance and many other automatic video systems. In this paper, we describe a novel method for the human action recognition from its silhouette in the video. In the algorithm, diffusion maps is used for dimensionality reduction as well as to preserve much of the geometrical structure. A global geometry and local temporal similarity...
This paper described the inherent local minimum problem and oscillations in the presence of obstacles or in narrow passages of traditional potential field methods for mobile robots in planar and static environment. Based on the character of a flow of water, this paper proposes a new method of obstacle avoiding trajectory using potential grid method. The main benefits of the method are the quickness...
Compared with serial robots, because of some advantages, e.g. higher stiffness, errors will not accumulated, parallel robot has much potential use. To 3-RPS parallel robot, there are 3 controllable degrees of freedom (axis x, axis y, axis z, or angle x, angle y, axis z). It may be called position kinematics or posture kinematics. According to structural characteristics of the 3-RPS parallel robot,...
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