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Robot-assisted minimally invasive surgery can benefit from the automation of common, repetitive or well-defined but ergonomically difficult tasks. One such task is the scanning of a pick-up endomicroscopy probe over a complex, undulating tissue surface to enhance the effective field-of-view through video mosaicing. In this paper, the da Vinci® surgical robot, through the dVRK framework, is used for...
Hamilton-Jacobi (HJ) reachability is a method that provides rigorous analyses of the safety properties of dynamical systems. These guarantees can be provided by the computation of a backward reachable set (BRS), which represents the set of states from which the system may be driven into violating safety properties despite the system's best effort to remain safe. Unfortunately, the complexity of the...
Simultaneous localization and mapping (SLAM) is one of the most challenging problems of mobile robots. An improved RGB-D visual SLAM algorithm is proposed in this paper, which based on the wheeled mobile robot to solve the problem of accumulative position error and large computation existed in the traditional algorithm. In order to overcome the error caused by the superposition of frames, a semi-random...
We present a novel approach for collision-free global navigation for continuous-time multi-agent systems with general linear dynamics. Our approach is general and can be used to perform collision-free navigation in 2D and 3D workspaces with narrow passages and crowded regions. As part of pre-computation, we compute multiple bridges in the narrow or tight regions in the workspace using kinodynamic...
In this paper, we introduce an informative path planning (IPP) framework for active classification using unmanned aerial vehicles (UAVs). Our algorithm uses a combination of global viewpoint selection and evolutionary optimization to refine the planned trajectory in continuous 3D space while satisfying dynamic constraints. Our approach is evaluated on the application of weed detection for precision...
Autonomous robot navigation through unknown, cluttered environments at high-speeds is still an open problem. Quadrotor platforms with this capability have only begun to emerge with the advancements in light-weight, small form factor sensing and computing. Many of the existing platforms, however, require excessive computation time to perform collision avoidance, which ultimately limits the vehicle's...
This paper presents a method for constructing 3D maps of marine archaeological sites using deployments of Autonomous Underwater Vehicles (AUV) equipped with sonar and cameras. The method requires multiple AUV missions in which the first mission directs the AUV to conduct a high altitude lawnmower scan over the area to create a course bathymetry map using sonar. Subsequent AUV missions then direct...
This paper is devoted to the problem of optimal weather routing for transoceanic ship voyages. The goal of optimization is to reduce travel time and fuel consumptions. The optimal route is searched on the admissible set, which comprises routes satisfying all of the imposed static and dynamic constraints. The static constraints are represented mostly by coastal lines and shallow waters. The dynamic...
Robot Coverage Path planning (i.e., the process of providing full coverage of a given domain by one or multiple robots) is a classical problem in the field of robotics and motion planning. The goal of such planning is to provide nearly full coverage while also minimize duplicately visited area. In this paper, we focus on the scenario of path planning on general surface, including planar domains with...
For a manipulation skill to be applicable to a wide range of scenarios, it must generalize between different objects and object configurations. Robots should therefore learn skills that adapt to features describing the objects being manipulated. Most of these object features will however be irrelevant for generalizing the skill and, hence, the robot should select a small set of relevant features for...
The machines can work like human or even better with the rapid development of the artificial intelligence (AI) in nowadays. More and more researchers have taken the demand about the interactivity of machine seriously. Human motion recognition that is a fundamental topic in robotics that try to make the machines to understand humans action. While the existing frameworks of motion recognition often...
Understanding visual attention has always been a topic of great interest in the graphics, image/video processing, robotics and human-computer interaction communities. By understanding salient image regions, the compression, transmission and rendering algorithms can be optimized. This is particularly important in omnidirectional images (ODIs) viewed with a head-mounted display (HMD), where only a fraction...
Robotics-assisted needle steering can enhance the performance of needle-based clinical procedures such as biopsy, brachytherapy, and drug delivery. We present an automated needle steering system capable of steering needles in 3D toward targets in tissue while avoiding anatomical obstacles. The system comprises a nonholonomic model of needle steering in tissue and a nonlinear controller for 3D trajectory...
This paper presents a path planning method based on Pythagorean Hodograph (PH) curves and harmony search algorithm for unmanned-aerial-vehicles (UAVs) in complex environments, especially in urban environment and mountainous circumstances. The flyable paths are tuned to meet spatial demands, satisfy kinematical and dynamic constraints of the UAVs, and guarantee no collision course between any two vehicles...
Action recognition is considered a promising field in computer vision and can be used in many applications such as video indexing and retrieval. In this paper, we present a novel technique for action recognition based on traditional three stages of feature extraction, action learning, and action recognition. The proposed technique builds a foreground snippet from the input video file, then uses integral...
Recently, C-arm cone-beam CT systems have been used to acquire knee joints under weight-bearing conditions. For this purpose, the C-arm acquires images on a horizontal trajectory around the standing patient, who shows involuntary motion. The current state-of-the-art reconstruction approach estimates motion based on fiducial markers attached to the knee. A drawback is that this method requires calibration...
Tracking failure is an inevitable event in real-time monocular simultaneous localization and mapping (SLAM) system. Relocalization procedure that focuses on exploring a visited place to relocalize a camera is usually used to handle this problem. However, this strategy abandons the poses of the frames captured after tracking failure, resulting in losing a part of trajectory with respect to the ground...
We study simultaneous localization and mapping with a device that uses reflections to measure its distance from walls. Such a device can be realized acoustically with a synchronized collocated source and receiver; it behaves like a bat with no capacity for directional hearing or vocalizing. In this paper we generalize our previous work in 2D, and show that the 3D case is not just a simple extension,...
Inferring the pose and shape of vehicles in 3D from a movable platform still remains a challenging task due to the projective sensing principle of cameras, difficult surface properties e.g. reflections or transparency, and illumination changes between images. In this paper, we propose to use 3D shape and motion priors to regularize the estimation of the trajectory and the shape of vehicles in sequences...
This paper involves trajectory planning for a low-cost UAV with limited sensing capability. The UAV must be able to safely reach its destination provided it can only gather limited information about its environment. We apply the velocity obstacle approach since it is applicable even with our model's limitation. When an obstacle is detected, the only information available is the distance to the obstacle...
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