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This paper presents a new approach to fuel-optimal path planning of multiple vehicles using a combination of linear and integer programming. The basic problem formulation is to have the vehicles move from an initial dynamic state to a final state without colliding with each other, while at the same time avoiding other stationary and moving obstacles. It is shown that this problem can be rewritten...
The paper presents a method for decentralized global formation stabilization of a group of several autonomous vehicles described by the standard kinematics equation with hard constraints on the vehicles' linear and angular velocities.
This paper addresses the problem of steering a quadrotor vehicle along a time-dependent trajectory. The problem is formulated so as to take into account force disturbances acting on the vehicle and enforce bounds on the actuation. The proposed solution consists of a nonlinear adaptive state feedback controller for thrust and torque actuation that i) guarantees asymptotic stability of the closed-loop...
This paper deals with the energy based control of a group of interconnected vehicles modeled as point masses. The control design is carried out by first shaping the kinetic energy and afterwards adding virtual potential energy and dissipative terms in order to achieve the desired stability performance. We assume that the vehicles move on a 2D surface and apply the results to simple examples with two...
The continuously increasing daily traffic congestions on motorway networks call for innovative control measures that would drastically improve the current traffic conditions. Mainstream traffic flow control (MTFC) is proposed as a novel motorway traffic management tool. Its possible implementation and principal impact on traffic flow efficiency is analysed. Variable speed limits, suitably operated...
This paper describes a method for station keeping and docking of floating vehicles. We consider the case of a lighter-than-air blimp and that of an underwater robot. Due to the motion disturbances in the environment (currents), these tasks are important to keep the vehicle stabilized relative to an external reference frame. The main difficulties to achieve station keeping and docking are related to...
Two kinds of observers, the classical extended deterministic Kalman filter and a high gain observer, have been applied to a nonlinear horizontal plane vehicle model. Observability conditions are given. We have shown that uniform local observability can be guaranteed. Finally, the two state estimators are compared and analyzed in simulations.
The use of integral or adaptive actions for the control problem of Autonomous Underwater Vehicles (AUVs) and Remotely Operated Vehicles (ROVs) is discussed in this paper. Generally speaking, the control laws are designed with respect to a mathematical model expressed either in the earth-fixed frame or in the vehicle-fixed frame. These two approaches, however, do not take into account the different...
This paper describes a solution to the problem of trajectory tracking control of autonomous surface craft (ASC) in the presence of constant ocean currents. The solution proposed is rooted in nonlinear model predictive control (MPC) techniques and addresses explicitly state and input constraints. Whereas state saturation constraints are added to the underlying optimization cost functional as penalties,...
This paper proposes a novel piecewise linear feedback control strategy for the automotive dry clutch engagement process. Based on a dynamic model of the powertrain system, the controller is designed by minimizing a quadratic performance index subject to constraints on the inputs and on the states. The resulting model predictive controller is shown to consist of a piecewise linear feedback control...
The problem of the path generation for the autonomous robot vehicle in environment with stationary and moving obstacles is considered. An algorithm, named MKBC, based on modified Kohonen rule and behavioral cloning is developed. The MKBC algorithm, as improvement of RBF neural network, uses the training values as weighting values, rather then values from the previous time. This enables an intelligent...
This paper focuses on path following algorithms for mobile robots with velocity constraints on the wheels. The path considered consists of straight lines intersected with given angles. We present a fast real-time receding horizon controller which anticipates the intersections and smoothly controls the robot through the turnings while fulfilling the velocity constraints.
Traffic congestion is a widespread problem. Dynamic traffic routing systems and congestion pricing are getting importance in recent research. Lane prediction and vehicle density estimation is an important component of such systems. We introduce a novel problem of vehicle self positioning which involves predicting the number of lanes on the road and vehicle's position in those lanes using videos captured...
In this paper, we describe a novel method using only optical flow from a single camera and inertial information to quickly initialize, deploy, and autonomously stabilize an inherently unstable aerial vehicle. Our approach requires a minimal number of tracked features in only two consecutive frames and inertial readings eliminating the need of long feature tracks or local maps and rendering it inherently...
This paper presents a new approach to the detection of a vehicle with low relative speed to a monocular moving camera, for complementing moving vehicle detection using motion vectors from H.264/AVC encoder. This method makes use of the generic horizontal line features that exist on most vehicles as a clue of localizing moving vehicles. Further filtering and grouping of these detected lines followed...
This paper describes a trust-based vehicle controller that can be tuned to ensure decentralized string stability in a convoy. The controller leverages the RoboTrust algorithm to mitigate risks associated with trust-based vulnerabilities, such as cyber attacks, poor decisions, and malfunctions. In our scenario, we simulate a simple convoy mission in which twelve vehicles move together between waypoints,...
This paper presents a performance comparison study between the space-vector and carrier-based PWM techniques used for neutral point clamped (NPC) 3-level inverter. A reduced switching loss based modulation technique is used for the SVPWM scheme and a third harmonic injected PWM technique is used for the carrier-based PWM scheme. A 110 kW surface-PMSM is used with the NPC inverter, as generally being...
It has been proved that the adoption of traffic sensing data can reduce traffic jam, and improve traffic volume. However, traffic sensing by both vehicles and road monitoring infrastructures faces the problem of data missing on dimensions of time and space, which makes data reconstruction a challenge for full-time and wide-area traffic sensing. Exploiting the hidden structure of the traffic data,...
This paper addresses the problem of stabilizing and trajectory tracking control of a remotely operated vehicle (ROV-Observer) in the vertical plane. The underwater vehicle is not actuated in the pitch direction and cannot be locally asymptotically stabilized by continuous feedbacks which are functions of the state only. In the present note, exponential convergence is obtained by considering time-varying...
DTN is a type of network with the routing strategy of storage and forward. Owing to the character of high latency, low transfer rate and intermittent connectivity, it is difficult to maintain the reliability of end to end paths. Hence the research of DTN protocol is meaningful and critical. In this paper, we assume a vehicle network scenario in the disaster. There exists significant performance degradation...
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