Reasoning about the past on temporal specifications for motion planning

2014 ◽  
Author(s):  
Everardo Barcenas ◽  
Antonio Benitez ◽  
Jorge de la Calleja ◽  
Maria Auxilio Medina ◽  
Jorge Rios-Martinez
Keyword(s):  
Motion Planning ◽  
The Past ◽  
Temporal Specifications

How multiple past tenses divide the labor: The case of South Baffin Inuktitut

Linguistics ◽  
2015 ◽  
Vol 53 (4) ◽  
Author(s):  
Midori Hayashi ◽  
David Y. Oshima
Keyword(s):  
The Other ◽  
Past Tense ◽  
Layered System ◽  
Fine Grained ◽  
The Past ◽  
Linear Scheme ◽  
Temporal Specifications ◽  
Past Tenses ◽  
Common Perception ◽  
Masculine Gender

AbstractIt is a common perception that in languages having multiple past tenses with different remoteness specifications, the past tenses cover the entire past without a gap or overlap. This paper demonstrates that this way of looking at multiple-past tense systems is not appropriate for the system in South Baffin Inuktitut (a variety of the Inuit language). The dialect has at least four past tenses: recent, hodiernal, pre-hodiernal, and distant. We argue that the relation between the four tenses cannot be represented by a simple linear scheme for two reasons. First, the pre-hodiernal past has a special status as the “conventionally designated alternative”, which is chosen in cases of remoteness indeterminacy, analogous to, for example, the Russian masculine gender being used in cases of gender indeterminacy. Second, there is overlap in their coverage. The pre-hodiernal and hodiernal past tenses collectively cover the entire past and thus any past situation can be described with one of them. The other two provide means to make more fine-grained and subjective temporal specifications. Comparison will be made between the system in South Baffin Inuktitut and those in some Bantoid languages which have been pointed out in the literature to have a comparable layered system of tenses.

A dynamic singularity-based design of a free-flying planar manipulator

2007 ◽  
Vol 221 (6) ◽  
pp. 563-659
Author(s):  
A DasGupta
Keyword(s):  
Motion Planning ◽  
Planning Problem ◽  
Space Robots ◽  
Dynamic Design ◽  
The Past ◽  
On Line ◽  
Singularity Point ◽  
Motion Planning Problem

A new methodology for dynamic design of a planar free-flying manipulator with the objective of simplifying the non-holonomic motion planning problem is proposed. As has been proposed in the past, the dynamic singularity point can be effectively used for non-holonomic motion planning of space robots. The proposed design imparts special properties to the dynamic singularity point, which are useful for the motion planning problem. Making use of the dynamic singularity of the manipulator, the motion planning problem can then be solved on-line. Example of a two-link planar manipulator mounted on a satellite base is used to present the proposed theory.

scholarly journals Motion planning and posture control of multiple n-link doubly nonholonomic manipulators

Robotica ◽  
2015 ◽  
Vol 35 (1) ◽  
pp. 1-25 ◽  
Author(s):  
Bibhya Sharma ◽  
Jito Vanualailai ◽  
Shonal Singh
Keyword(s):  
Motion Planning ◽  
Computer Simulations ◽  
Arbitrary Number ◽  
Posture Control ◽  
Mobile Manipulators ◽  
Moving Obstacles ◽  
The Past ◽  
Control Scheme ◽  
Lyapunov Control ◽  
Final Orientation

SUMMARYThe paper considers the problem of motion planning and posture control of multiple n-link doubly nonholonomic mobile manipulators in an obstacle-cluttered and bounded workspace. The workspace is constrained with the existence of an arbitrary number of fixed obstacles (disks, rods and curves), artificial obstacles and moving obstacles. The coordination of multiple n-link doubly nonholonomic mobile manipulators subjected to such constraints becomes therefore a challenging navigational and steering problem that few papers have considered in the past. Our approach to developing the controllers, which are novel decentralized nonlinear acceleration controllers, is based on a Lyapunov control scheme that is not only intuitively understandable but also allows simple but rigorous development of the controllers. Via the scheme, we showed that the avoidance of all types of obstacles was possible, that the manipulators could reach a neighborhood of their goal and that their final orientation approximated the desired orientation. Computer simulations illustrate these results.

scholarly journals Pure-Past Linear Temporal and Dynamic Logic on Finite Traces

2020 ◽  
Author(s):  
Giuseppe De Giacomo ◽  
Antonio Di Stasio ◽  
Francesco Fuggitti ◽  
Sasha Rubin
Keyword(s):  
Decision Making ◽  
Dynamic Logic ◽  
Expressive Power ◽  
Decision Problems ◽  
Sequential Decision Making ◽  
Sequential Decision ◽  
The Past ◽  
Temporal Specifications

We review PLTLf and PLDLf, the pure-past versions of the well-known logics on finite traces LTLf and LDLf, respectively. PLTLf and PLDLf are logics about the past, and so scan the trace backwards from the end towards the beginning. Because of this, we can exploit a foundational result on reverse languages to get an exponential improvement, over LTLf /LDLf , for computing the corresponding DFA. This exponential improvement is reflected in several forms of sequential decision making involving temporal specifications, such as planning and decision problems in non-deterministic and non-Markovian domains. Interestingly, PLTLf (resp., PLDLf ) has the same expressive power as LTLf (resp., LDLf ), but transforming a PLTLf (resp., PLDLf ) formula into its equivalent LTLf (resp.,LDLf) is quite expensive. Hence, to take advantage of the exponential improvement, properties of interest must be directly expressed in PLTLf /PLDLf .

scholarly journals A One-Pass Tree-Shaped Tableau for LTL+Past

10.29007/3hb9 ◽  
2018 ◽  
Author(s):  
Nicola Gigante ◽  
Angelo Montanari ◽  
Mark Reynolds
Keyword(s):  
Artificial Intelligence ◽  
Computer Science ◽  
Temporal Logic ◽  
Expressive Power ◽  
Temporal Constraints ◽  
Temporal Logics ◽  
The Past ◽  
Tableau System ◽  
Standard Formalism ◽  
Temporal Specifications

Linear Temporal Logic (LTL) is a de-facto standard formalism for expressing properties of systems and temporal constraints in formal verification, artificial intelligence, and other areas of computer science. The problem of LTL satisfiability is thus prominently important to check the consistency of these temporal specifications. Although adding past operators to LTL does not increase its expressive power, recently the interest for explicitly handling the past in temporal logics has increased because of the clarity and succinctness that those operators provide. In this work, a recently proposed one-pass tree-shaped tableau system for LTL is extended to support past operators. The modularity of the required changes provides evidence for the claimed ease of extensibility of this tableau system.

Design for Maintenance by Constrained Motion Planning

1995 ◽  
Author(s):  
Tsai-Yen Li ◽  
Hsuan Chang
Keyword(s):  
Motion Planning ◽  
Computer Animation ◽  
Industrial Applications ◽  
Automated System ◽  
Constrained Motion ◽  
Crucial Issue ◽  
Motion Constraints ◽  
The Past ◽  
Access Path ◽  
Cad Models

Abstract In designing an assembly product, maintainability is a crucial issue that determines whether certain parts can be accessed for routine maintenance. In the past its study has been largely manual and labor intensive. Either by using physical mockup or computer animation with CAD models of a design, the task relies on human to provide an access path for the part. In this paper we present an automated system that replaces the traditional manual process. By applying results from and developing extensions to the motion planning research in robotics, we demonstrate that this automated system is an effective addition to CAD systems. We specifically describe the extension that accounts for special motion constraints imposed by designers. We also present experimental results from applying such a system to problems in industrial applications. The results show that such an system can not only reduce the turn-around time for checking maintainability of a product but also provide more accurate feedback to the designers on potential maintenance problems.

Extending RRT for Robot Motion Planning with SLAM

2012 ◽  
Vol 151 ◽  
pp. 493-497 ◽  
Author(s):  
Hai Zhu Pan ◽  
Jin Xue Zhang
Keyword(s):  
Genetic Algorithms ◽  
Mobile Robot ◽  
Motion Planning ◽  
Cell Decomposition ◽  
Potential Fields ◽  
Robot Motion ◽  
Planning Problem ◽  
Robot Motion Planning ◽  
The Past ◽  
Road Maps

In this paper,the motion planning problem for mobile robot is addressed. Motion planning (MP) has diversified over the past few decades to include many different approaches such as cell decomposition, road maps, potential fields, and genetic algorithms. Often the goal of motion planning is not just obstacle avoidance but optimization of certain parameters as well. A motion planning algorithms based on Rapidly-exploring random Tree(RRT) is present in the paper. Then the RRT algorithm has been extended which combines the SLAM algorithm.The Extend-RRT-SLAM has been simulated in MobileSim.Simulation results show Extend-RRT-SLAM to be very effective for robot motion planning.

Observations of the continuum near the galactic centre

1967 ◽  
Vol 31 ◽  
pp. 405
Author(s):  
F. J. Kerr
Keyword(s):  
Galactic Centre ◽  
The Past ◽  
Centre Region ◽  
The Continuum

A continuum survey of the galactic-centre region has been carried out at Parkes at 20 cm wavelength over the areal11= 355° to 5°,b11= -3° to +3° (Kerr and Sinclair 1966, 1967). This is a larger region than has been covered in such surveys in the past. The observations were done as declination scans.

The Origin of the Moon and its Relationship to the Origin of the Solar System

1962 ◽  
Vol 14 ◽  
pp. 133-148 ◽  
Author(s):  
Harold C. Urey
Keyword(s):  
Solar System ◽  
The Moon ◽  
The Past ◽  
The Earth ◽  
Short Period ◽  
Origin Of The Moon

During the last 10 years, the writer has presented evidence indicating that the Moon was captured by the Earth and that the large collisions with its surface occurred within a surprisingly short period of time. These observations have been a continuous preoccupation during the past years and some explanation that seemed physically possible and reasonably probable has been sought.

On The Possibility of an Autonomous History of Modern Southeast Asia

1961 ◽  
Vol 2 (2) ◽  
pp. 73-105 ◽  
Author(s):  
John R. W. Small
Keyword(s):  
Southeast Asia ◽  
Contemporary History ◽  
The Past ◽  
History Of

It is generally accepted that history is an element of culture and the historian a member of society, thus, in Croce's aphorism, that the only true history is contemporary history. It follows from this that when there occur great changes in the contemporary scene, there must also be great changes in historiography, that the vision not merely of the present but also of the past must change.

Sign in / Sign up

Export Citation Format

Share Document