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The need for combined task and motion planning in robotics is well understood. Solutions to this problem have typically relied on special purpose, integrated implementations of task planning and motion planning algorithms. We propose a new approach that uses off-the-shelf task planners and motion planners and makes no assumptions about their implementation. Doing so enables our approach to directly...
We present a mathematical programming-based method for optimal control of discrete-time dynamical systems subject to temporal logic task specifications. We use linear temporal logic (LTL) to specify a wide range of properties and tasks, such as safety, progress, response, surveillance, repeated assembly, and environmental monitoring. Our method directly encodes an LTL formula as mixed-integer linear...
Fiber tracking is a mature technique that aids neurosurgeons by providing the location of neuronal fibers in a patient's brain. Although the interactivity of tools have been typically limited, the exploitation of the parallel nature of fiber tracking is rapidly changing this landscape. The parallel environment offered by GPUs and modern CPUs enables fiber tracking to be executed very quickly on consumer-grade...
In this paper, we propose a novel method for learning motor skills based on grossness and fineness of movements involved in daily-life tasks. Grossness and fineness depend on the degrees of complexity (i.e., linear combinations between basis vectors) and repeatability (i.e., repeat accuracies between multiple trials) of such movements. In such a daily-life task, a robot's movements are usually related...
In this paper a characterization of the new concept of entropy of a dynamic system is discussed. A new graphical approach is used to quickly get a feeling of the local nonlinearity of planar dynamical systems. A user-friendly tool in MATLAB/Simulink has been designed in order to automatize computation of the entropy and easy visualization as color maps.
This work is part of a technical study of the French space agency CNES (Centre National d'Etudes Spatiales) and the French aerospace laboratory Onera for the development of an air-launch-to-orbit system. This system, based on a dedicated aircraft and a space rocket, aims at offering more flexible dates and trajectories to micro-satellite launching missions. The separation phase between the carrier...
In this paper, we propose a novel passive micromixer structure based on the effect of stretching-folding in both vertical and horizontal directions. The channel depth of the micromixer is tightened at two ends each mixing unit. The fluid flows are repeatedly twisted and bent from left to right and vice versa. With this special structure, our proposed micromixer can create vortices and transversal...
We study the dynamics of accelerating beams impinging on different classes of index potentials. The analytic expressions for the reflected and transmitted waves show that the Airy-wave parabolic trajectory is modified with some particular exceptions.
Movement in bed may be an indicator of health problems, i.e., the alteration of the pattern or amount of motor activity can be a disease marker. It can reflect illnesses ranging from flu to depression, pain, or the side effects of certain treatments. There are also motor disturbances that are triggered by sleep such as restless legs syndrome and periodic limb movements during sleep that reduce sleep...
This paper outlines and demonstrates a methodology and computational framework to explore the trade-space underlying airspace design. Airspace design includes several key aspects. The first is what activity is done, captured as ‘actions’ in the simulation.
Heterogeneity and stability of the agricultural landscape is the premise to maintain the stability and high-efficient of agricultural ecosystem. Disturbance regimes have been recognized as the causes of the landscape heterogeneity. In this paper, the Fengqiu County, a typical agricultural region in the lower reaches of the Yellow River plains, was selected as the study area. Based on the TM imagery...
This paper defines the existing navigation and location services data and six kinds of retrieval patterns. By contrasting to the existing trajectory index methods, we propose several index algorithms of different dimensions in the MapReduce mode, particularly, a spatiotemporal index algorithm named Layer-by-layer Index Based on Grid Partition (LIBGP), which efficiently avoids the problem of low trajectory...
With the growth of location-based services and social services, low-sampling-rate trajectories from check-in data or photos with geo-tag information becomes ubiquitous. In general, most detailed moving information in low-sampling-rate trajectories are lost. Prior works have elaborated on distant-time location prediction in high-sampling-rate trajectories. However, existing prediction models are pattern-based...
The goal of this work is to teach a robot to regrasp an object using knowledge obtained from human demonstration. This paper presents a task model that represents a human regrasping movement. The task model is based on the topological information and comprised of four task primitives. Human regrasping movement is recognised and represented as a sequence of these task primitives by the proposed recognition...
This work applies the popular reinforcement learning methodology of Q learning in a typical robot control navigation problem. It is a two dimensional (2D) set-up where a robot tries to learn its path through its environment by avoiding any obstacles that may be encountered on its way from its home to a final destination (a goal state). During the navigation, trajectory of all the state-action pairs...
This paper proposes an evaluation method for human hitting motion skill. The hitting motion is one of basic motions, in which a human often employs a tool to move or convert an object. Also, hitting skill is an important performance desired in many sports, such as tennis and baseball, and also in the field of traditional crafts, such as nailing and forging. In proposed method, the hitting skill using...
In this article we propose a shooting algorithm for optimal control problems governed by systems that are affine in one part of the control variable. Finitely many equality constraints on the initial and final state are considered. We recall a second order sufficient condition for weak optimality, and show that it guarantees the local quadratic convergence of the algorithm. We show an example and...
In this paper, a 2D Flattened Maxwell fish-eye (MFE) lens is proposed using transformation optics, which transforms a traditional MFE lens into a flattened MFE lens. The coordinate transformation is presented from a circular to a rectangular domain. We also discussed the rotated ray trajectories in MFE lens. The required permittivity and permeability tensors are derived for the flattened MFE lens...
Spatio-temporal co-occurring patterns represent subsets of event types that occur together in both space and time. In comparison to previous work in this field, we present a general framework to identify spatio-temporal co occurring patterns for continuously evolving spatio-temporal events that have polygon-like representations. We also propose a set of measures to identify spatio-temporal co-occurring...
In this paper, we develop theoretical results based on a proposed method for modeling switching noise for a class of hybrid systems with piecewise linear partitioned state space, and state-depending switching. We devise a stochastic model of such systems, whose global dynamics is governed by a continuous-time stochastic process. The main result of this paper is that we may identify the realizations...
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