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Subsea interventions in the oil & gas industry as well as in other domains such as archaeology or geological surveys are demanding and costly activities for which robotic solutions are often deployed in addition or in substitution to human divers — contributing to risks and costs cutting. The operation of ROVs (Remotely Operated Vehicles) nevertheless requires significant off-shore dedicated manpower...
In this paper, we discuss event-triggering scheme with sliding mode control where sensors are distributed over network. Here, a decentralized event-triggering mechanism is proposed where event is observed at each sensor nodes with local information for possible triggering and control update is done whenever a centralized event is triggered. In order to achieve this, the states are sampled at any one...
Central catadioptric omnidirectional images exhibit serious nonlinear distortions due to quadratic mirrors involved. Conventional visual features developed based on the perspective model are hard to achieve a satisfactory performance when directly applied to the distorted omnidirectional image. This paper presents a parameterized neighborhood model to efficiently calculate the adaptive neighborhood...
This paper demonstrates the evaluation of a rule-based control strategy for an equalization facility in front of an industrial wastewater treatment plant. The control goal is not only to dampen the flow rate but also the waste concentration and the load since its huge influence on the subsequent processes. This is complicated by the technical and financial constraints of the process. Overall, the...
In this paper1 we consider a multiuser detection scheme for space division multiple access communication systems. Sequential interference cancellation (SIC) procedures are subject to performance degradation when the antenna array is only partially calibrated. We propose to incorporate robust beamforming algorithms into the SIC procedure to compensate for the array misalignment. We show by a simulation...
The paper proposes a robust soft sensor for on-line monitoring of the mixing water quality in dynamic water networks. A complete hydraulic information is assumed to be available on-line. Robustness of the water quality parameter estimates is achieved by non-probabilistic set-bounded modelling of uncertainty in the measurement and modelling errors. The stable and tight bounds on the estimated quantities...
In recent years several approaches have been proposed to compensate for the hysteresis behavior of piezo actuators. However, they are very restrictive, either on the hardware side or in the choice of possible reference trajectories. In this paper, alternative hysteresis compensators for arbitrary trajectories are presented which use standard equipment. Two approaches of different complexity are proposed...
When local tracks are fused to produce a global track, allowing for dependence, the approximations necessary for economic track representation can result in an unlocalised, posterior track distribution and tracker failure. This paper describes two approaches to robust track fusion. Each produces a modified version of the usual formula which undoes the adverse effects of the approximations. The general...
This paper presents methods to design the control loops for different device layouts of rate gyroscopes by modeling the micromachined rate gyroscope structures, where the very low damping of the system and plant parameter variations due to production tolerances and variability of the environment are considered. A robust controller to rebalance the seismic mass is designed for the detection loop using...
Closed-loop control of separated flows is still hindered by a lack of fast and practical sensors for the measurement of the length of a separation bubble or of the position of reattachment. Therefore, a new real-time algorithm for the online detection of flow states is developed to overcome this limitation. For a model-based sensor microphone measurements in the separation zone are exploited and a...
Wireless sensor networks have a wide range of applications such as automatic monitoring systems and target tracking. This paper proposes and evaluates the performance of a cooperative modulation diversity technique applied to heterogeneous wireless sensor networks. The evaluation of the impacts between the energy factor, lifetime, the channel Signal-to-Noise Ratio (SNR) and the packet loss rate is...
We consider ill-posed linear inverse problems involving the estimation of structured sparse signals. When the sensing matrix has i.i.d. standard normal entries, there is a full-fledged theory on the sample complexity and robustness properties. In this work, we propose a way of making use of this theory to get good bounds for the i.i.d. Bernoulli ensemble. We first provide a deterministic relation...
In this contribution, we implement a fully distributed diffusion field estimation algorithm based on the use of average consensus schemes. We show that the field reconstruction problem is equivalent to estimating the sources of the field, and then derive an exact inversion formula for jointly recovering these sources when they are localized and instantaneous. Next we adapt this formula to the sensor...
The paper investigates combining Compressive Sensing (CS) with the robust Capon beamformer (RCB) for the purpose of medical ultrasound image formation with a much reduced number of samples compared to those used in current state-of-art ultrasound. The proposed CS algorithm uses wave atom dictionary as a low dimension projection, a Bernouli random matrix as a sensing matrix and a regularized-l1 optimization...
Recently, we demonstrated that random projections can provide an extremely compact representation of a camera fingerprint without significantly affecting the matching performance. In this paper, we propose a new construction that makes random projections of camera fingerprints scale-robust. The proposed method maps the compressed fingerprint of a rescaled image to the compressed fingerprint of the...
We present a robust method to identify and isolate faulty sensors among a set of correlated sensors. For each sensor, we estimate the sensor a number of times, using each of the other correlated sensors separately. We use the median of these estimates as the estimate for the sensor. When up to less than half of the sensors are faulty, this method identifies the faulty sensors accurately. Since the...
In this paper, adaptive threshold generation for robust fault detection is analyzed. Uncertainties due to parameter variations are considered in the system model using an interval model. An interval observer is used as a suitable passive robust strategy to generate an adaptive threshold by propagating uncertainty to the residuals. The design procedure of this observer is implemented via pole placement...
Wireless Sensor Networks (WSNs) are becoming fundamental components of modern control systems. Although WSNs provide tremendous advantages in versatility, their use poses new issues in the design of the control system, in particular the discharge of batteries of sensor nodes, which is mainly due to radio communications, must be taken into account. In a previous work, for the case of a single wireless...
In this paper, a methodology is proposed to deal with the problem of multiple and simultaneous fault isolation on large systems. The goal which is pursued, is to merge already in place fault indicating signals and model-based fault indicating signals (i.e. the residuals), in order to solve the isolation problem. Behind this goal, the problem of the minimal number of residuals is addressed. This includes...
Fault Tolerant Controls are highly reliable control systems aimed at increasing system reliability and reducing safety hazards. FTCs are designed to accommodate faults at their early stage of development to prevent those minor faults from developing into failures that might jeopardize system stability and availability. FTC design is a topic of active and ongoing research activities with applications...
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