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Collision-free state estimation

Lawson L.S. Wong, Leslie Pack Kaelbling, Tomas Lozano-Perez
2012 2012 IEEE International Conference on Robotics and Automation  
We illustrate this for estimating collision-free configurations for objects resting stably on a 2-D surface, and demonstrate its utility in a real robot perception domain.  ...  In state estimation, we often want the maximum likelihood estimate of the current state.  ...  GENERAL COLLISION-FREE STATE ESTIMATION Returning to the original problem (s j = {x j , y j , θ j }), we can formulate a similar optimization problem: s s s = arg min {s j } M j=1 M ∑ j=1 N j 1 2 s j Σ  ... 
doi:10.1109/icra.2012.6225309 dblp:conf/icra/WongKL12 fatcat:wufitcmfnnbufg2bjyy7brzzfu

Estimating probability of collision for safe motion planning under Gaussian motion and sensing uncertainty

Sachin Patil, Jur van den Berg, Ron Alterovitz
2012 2012 IEEE International Conference on Robotics and Automation  
previous stages being collision free.  ...  To improve accuracy, we use a novel method to truncate estimated a priori state distributions to account for the fact that the probability of collision at each stage along a plan is conditioned on the  ...  The conditional distributions computed using our method provide an accurate estimate of the distribution of the collision free robot states along the plan, thus providing an accurate estimate of the probability  ... 
doi:10.1109/icra.2012.6224727 dblp:conf/icra/PatilBA12 fatcat:hshcekn2krcqlki2lfredofbw4

Air traffic complexity and the interacting particle system method: An integrated approach for collision risk estimation

Maria Prandini, Henk A. P. Blom, G. J. Bakker
2011 Proceedings of the 2011 American Control Conference  
This makes it impracticable for estimating the probability of a rare event such as a collision, and calls for ad-hoc solutions.  ...  Preliminary results obtained by applying this integrated approach to a free flight scenario are presented in the paper.  ...  Hence, the en-route free flight safety verification problem consists of estimating the collision probability of free flight operations, and comparing this estimate with the ICAO established thresholds  ... 
doi:10.1109/acc.2011.5991305 fatcat:mydn7it6xrh4bej45rzgybfw7m

Diagnostics of a charge breeder electron cyclotron resonance ion source helium plasma with the injection ofNa231+ions

O. Tarvainen, H. Koivisto, A. Galatà, J. Angot, T. Lamy, T. Thuillier, P. Delahaye, L. Maunoury, D. Mascali, L. Neri
2016 Physical Review Accelerators and Beams  
The obtained data allows estimating the upper limit for the ion-ion collision mean-free path of the incident sodium ions, the lower limit of ion-ion collision frequencies for all charge states of the sodium  ...  The ion-ion collision frequencies of high charge state ions are shown to be at least on the order of 1-10 MHz and the plasma density is estimated to be on the order of 10 11 cm −3 or higher.  ...  The estimated upper limits of the ion mean-free paths and lower limits of the ion-ion collision frequency for different charge states of Na are displayed in Table III .  ... 
doi:10.1103/physrevaccelbeams.19.053402 fatcat:pktlisqdevfmhdmzmtol2ereqa

Page 411 of The Journal of Chemical Physics Vol. 29, Issue 2 [page]

1958 The Journal of Chemical Physics  
It is usually loosely stated that the ‘‘collision complex”’ is entered from the “‘free”’ state, A+B+C, as a result of a three-body collision and from the “bound” state, AB+C, as a result of a “two-body  ...  As a result of the above definition there are six ways for a three-body collision to occur in the “freestate and two ways for it to occur in the “bound” state.  ... 

Robust Filter Based Control of A Single-link Flexible Arm and Its Collision Detection Using Innovation Process

Yuichi Sawada, Tatsuya Fujimoto, Atsushi Moritani, Akio Tanikawa
2012 Proceedings of the ISCIE International Symposium on Stochastic Systems Theory and its Applications  
This paper describes a method of collision detection and control of a single-link flexible arm using a couple of state estimators.  ...  The controller generates a control torque based on the state estimate using the robust optimal filter. Collision detection is then realized by using the innovation of a Kalman filter.  ...  (10) State Estimators for Control and Collision Detection In this paper we employ two state estimators, i.e. one is for obtaining the state estimate for control; other one is for making the decision  ... 
doi:10.5687/sss.2012.19 fatcat:cnnqzk5qifh3xlybcfdwx3hsre

Motion sketching for control of rigid-body simulations

Jovan Popović, Steven M. Seitz, Michael Erdmann
2003 ACM Transactions on Graphics  
A multiple-shooting optimization estimates the parameters of a rigid-body simulation needed to simulate an animation that matches the sketch with physically plausible timing and motion.  ...  Sketches designed with the editing interface consist of several collision-free segments. The motion within each collision-free segment is parameterized by the initial state.  ...  For example, edits in the second collision-free segment adjust the initial state at the Fig. 9 .  ... 
doi:10.1145/944020.944025 fatcat:uncoswhhf5fr3k6urtwzyusfyi

Collision Avoidance Algorithm for Satellite Formation Reconfiguration under the Linearized Central Gravitational Fields

InYoung Hwang, Sang-Young Park, Chandeok Park
2013 Journal of Astronomy and Space Sciences  
PARAMETERIZATION OF THE COLLISION-FREE ENERGY OPTIMAL CONTROL PROBLEM Energy optimal control problem with collision avoidance constraints A collision-free optimal trajectory can be estimated by solving  ...  Similarly in the case of Sultan's algorithm forgravity-free space, way-points are introduced for collision avoidance and trajectories of satellites are represented by states of waypoints.  ... 
doi:10.5140/jass.2013.30.1.011 fatcat:4bghzfd7afgevmewrgaxjmr5ey

Characterizing High-Energy pp Collisions at the Large Hadron Collider using Thermal Properties [article]

Dushmanta Sahu, Raghunath Sahoo
2020 arXiv   pre-print
Particle species dependent mean free path and isobaric expansivity are studied as a function of final state charged particle multiplicity for pp collisions at √(s) = 7 TeV.  ...  In this work, we have estimated various thermal properties of the matter formed in high-energy pp collisions, like mean free path (Λ), isobaric expansivity (α), thermal pressure (∂ P/∂ T), heat capacity  ...  Taking these as inputs, we estimate Λ as a function of final state event multiplicity, which is shown in Fig. 3 .  ... 
arXiv:2005.12176v2 fatcat:foeifk2pjzh7rbkm7hhyhs7s6y

Thermodynamic and Transport Properties of Matter Formed in pp, p-Pb, Xe-Xe and Pb-Pb Collisions at the Large Hadron Collider using Color String Percolation Model [article]

Dushmanta Sahu, Raghunath Sahoo
2020 arXiv   pre-print
To have a better understanding of the matter formed in ultra-relativistic collisions, using the Color String Percolation Model (CSPM), we have estimated initial energy density, mean free path, squared  ...  The critical initial energy density and temperature as estimated by lattice QCD, are observed to be achieved for events with final state multiplicity 〈 dN_ch/dη〉≥ 20.  ...  These observations go in line with our recent estimations of particle dependent mean free path estimated using the identified particle spectra in a Tsallis non-extensive framework [54] .  ... 
arXiv:2006.04185v2 fatcat:f6baz3nx4baajdsczgef2joex4

Extended-State-Observer-Based Collision-Free Guidance Law for Target Tracking of Autonomous Surface Vehicles with Unknown Target Dynamics

Shengnan Gao, Zhouhua Peng, Dan Wang, Lu Liu
2018 Complexity  
Furthermore, the above result is extended to the case that collisions between the target and leader are avoided during tracking, and a collision-free target tracking guidance law is developed.  ...  First, a reduced-order extended state observer is used to estimate the unknown relative dynamics due to the unavailable velocity of the target.  ...  A reduced-order extended state observer is used to estimate the unknown relative dynamics.  ... 
doi:10.1155/2018/4154670 fatcat:qjnlsfnok5dnbd2rjcnq6ooufe

Free Flight Collision Risk Estimation by Sequential MC Simulation [chapter]

Henk Blom, Jaroslav Krystul, (Bert) Bakker, Margriet Klompstra, Bart Klein Obbink
2006 Automation and Control Engineering  
Hence, the en-route free flight safety verification problem consists of estimating the collision probability of free flight operations, and subsequently comparing this estimated level with the ICAO established  ...  The numerical challenge of this problem, however, differs from free flight collision risk estimation on the following aspects: Introduction of the state space by many orders in magnitude. • There are multiple  ... 
doi:10.1201/9781420008548.ch10 fatcat:pnochdve3rhqjdihlrfuj75b5a

Collision Detection and Control of Single-link Flexible Arm Using Optimal Disturbance Decoupling and Kalman Filters

Yuichi Sawada, Atsushi Moritani, Tatsuya Fujimoto, Akio Tanikawa
2012 Transactions of the Institute of Systems Control and Information Engineers  
This paper describes a method using coupled state estimators for collision detection and control of a single-link flexible arm.  ...  The controller generates a control torque based on the state estimate by using the Optimal Disturbance Decoupling Filter.  ...  Collision Detection We employ two state estimators.  ... 
doi:10.5687/iscie.25.336 fatcat:np2dgulqkrckheni73ld536i4i

Collision Detection and Control of Parallel-Structured Flexible Manipulators Based on Unscented Kalman Filter [chapter]

Yuichi Sawada, Yusuke Watanabe, Junki Kondo
2010 Advanced Strategies for Robot Manipulators  
the state vector of collision-free system.  ...  Nonlinear state estimation using UKF The state space model described by (21) and (22) is a stochastic nonlinear system with the collision input.  ...  How to reference In order to correctly reference this scholarly work, feel free to copy and paste the following: Yuichi Sawada, Yusuke Watanabe and Junki Kondo (2010) .  ... 
doi:10.5772/10195 fatcat:ygd6i3e3ujbgpeb2hv4skzdgnm

Collision Avoidance Using Spherical Harmonics [article]

Steven Patrick, Efstathios Bakolas
2021 arXiv   pre-print
In this paper, we propose a novel optimization-based trajectory planner that utilizes spherical harmonics to estimate the collision-free solution space around an agent.  ...  This contrasts with other state-of-the-art planners that generate trajectories by estimating obstacle boundaries with rough approximations and using heuristic rules to prune a solution space into one that  ...  With SH estimation of the collision-free space, our optimization-based path planner can produce less conservative trajectories than other state-of-the-art planners.  ... 
arXiv:2107.07117v1 fatcat:i54273zpmrakfb4sx7tclbb2nq
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