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This paper presents a method for estimating the number, as well as the activity periods of spatially distributed sound sources using an uncalibrated microphone array. This methodology is applied for the purposes of speaker diarization. In general, speaker diarization has difficulty with: 1) estimating the number of sound sources (speakers), and 2) activity detection of multiple sound sources including...
This paper adresses the problem of simultaneously estimating the state and the fault of nonlinear discrete-time stochastic systems in light of the unknown input filtering framework. The fault and unknown disturbances which may cause great estimate errors and even divergence of conventional filters, affect both the system state and the measurements. Inspired by the robust two stage Kalman filter for...
Unmanned Aerial Vehicles (UAVs) exhibit great agility and usually require a trained pilot to operate them, while being restricted to line-of-sight range. This prevents their wide introduction in applications such as inspection for disaster scenarios. Our goal is to enable rescue teams untrained in piloting to teleoperate a UAV as an aid to their mission, while being able to focus on the task at hand...
Advanced robotic technology has become a significant component in many medical specialties, including in rehabilitation tasks such as physiotherapy. Rehabilitation programs are a practical approach created to assist patients, such as stroke victims, in retrieving their missing functional capacity, obtaining new skills, and enhancing their quality of life. Nevertheless, rehabilitation treatments need...
Obstacle Detection is a central problem for any robotic system, and critical for autonomous systems that travel at high speeds in unpredictable environment. This is often achieved through scene depth estimation, by various means. When fast motion is considered, the detection range must be longer enough to allow for safe avoidance and path planning. Current solutions often make assumption on the motion...
In this paper, a robust trajectory tracking control strategy for a quadrotor flying robot is developed. At first, the quadrotor's dynamic model is obtained by Euler — Newton approach. Then, control strategy, consist of a robust linear H∞ control to track transitional movements for reference trajectory and a robust nonlinear H∞ control for rotational movements and rejecting the external disturbances...
Nowadays, the technological and scientific research related to underwater perception is focused in developing more cost-effective tools to support activities related with the inspection, search and rescue of wreckages and site exploration: devices with higher autonomy, endurance and capabilities. Currently, specific tasks are already carried out by remotely-operated vehicles (ROV) and autonomous underwater...
This article depicts an algorithm which matches the output of a Lidar with an initial terrain model to estimate the absolute pose of a robot. Initial models do not perfectly fit the reality and the acquired data set can contain an unknown, and potentially large, proportion of outliers. We present an interval based algorithm that copes with such conditions, by matching the Lidar data with the terrain...
Unmanned Aerial Vehicles (UAVs) are employed in surveillance, reconnaissance, and aerial photography. The dynamics of UAVs is highly nonlinear and inherently coupled. It also tends to vary continuously with time and is subjected to severe external disturbances. Due to this, dynamic and parametric uncertainties arise in the mathematical model of the UAVs over different operating conditions. In this...
Real-time and reliable localization is a prerequisite for autonomously performing high-level tasks with micro aerial vehicles(MAVs). Nowadays, most existing methods use vision system for 6DoF pose estimation, which can not work in degraded visual environments. This paper presents an onboard 6DoF pose estimation method for an indoor MAV in challenging GPS-denied degraded visual environments by using...
Two time-scale model based adaptive control method is proposed for a helicopter to overcome wind disturbances in this paper. Wind disturbances are considered as a mixture of four sinusoidal signals with unknown frequencies, amplitudes and phases. The controller is designed based on the concept of time-scale separation, which has the advantage of decoupling of the rotational and translational dynamics...
The capability to instantiate a cooperation among heterogeneous agents is a fundamental feature in mobile robotics. In this paper we focus on the interaction between Unmanned Ground Vehicle (UGV) and Unmanned Aerial Vehicle (UAV) to extend the endurance of UAV, thanks to a novel landing/recharging platform. The UGV acts as a docking station and hosts the UAV during the indoor/outdoor transition and...
The robust perception of robots is strongly needed to handle various objects skillfully. In this paper, we propose a novel approach to recognize objects and estimate their 6-DOF pose using 3D feature descriptors, called Geometric and Photometric Local Feature (GPLF). The proposed descriptors use both the geometric and photometric information of 3D point clouds from RGB-D camera and integrate those...
We present a monocular vision-based navigation system that incorporates two contrasting approaches: region segmentation that computes the road appearance, and road boundary detection that estimates the road shape. The former approach segments the image into multiple regions, then selects and tracks the most likely road appearance. On the other hand, the latter detects the vanishing point and road...
The ability to reconsider information over time allows to detect failures and is crucial for long term robust autonomous robot applications. This applies to loop closure decisions in localization and mapping systems. This paper describes a method to analyze all available information up to date in order to robustly remove past incorrect loop closures from the optimization process. The main novelties...
Camera pose estimation (perspective-n-points, or PnP) is a well-studied problem in computer vision with many applications in robotics. However state-of-art approaches often consider the task of pose estimation with respect to an object where the ratio between the furthest and closest point is small. Localisation in the context of simultaneous localisation and mapping (SLAM) violates this constraint...
Station keeping and trajectory tracking are necessary capabilities for underwater robotics vehicles (URVs), allowing them to maintain a reference position and orientation, or follow a reference path. Disturbances to the system are caused by wave-induced hydrodynamic forces acting on the vehicle, and sudden changes in parameters and operating variables. This can lead to degraded performance, accuracy,...
This paper presents an object recognition method; feature X-D such as Kanade- Lucas-Tomasi Feature (KLT)-D and Speeded-Up Robust Features (SURF)-D. The main idea of the proposed algorithm is to use distance method to achieve rotation and position invariance. The anchor point, a center point of the target boundary region, is proposed in this paper as the basis of the pose estimation and it can be obtained...
In this paper, we analyze the robustness of the PSO-based approach to parameter estimation of robot dynamics presented in “Part One”. We have made attempts to make the PSO method more robust by experimenting with potential cost functions. The simulated system is a cylindrical robot; through simulation, the robot is excited, samples are taken, error is added to the samples, and the noisy samples are...
In this paper, a novel vision system is proposed to estimate attention of people from rich visual clues for social robot to perform natural interactions with multiple participants in public environments. The vision detection and recognition modules include multi-person detection and tracking, upper-body pose recognition, face and gaze detection, lip motion analysis for speaking recognition, and facial...
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