416932
Parts Feeding on a Conveyor with a One Joint Robot
Abstract. This paper explores a method of manipulating a planar rigid part on a conveyor belt using a robot with just one joint. This approach has the potential of offering a simple and flexible method for feeding parts in industrial automation applications. In this paper we develop a model of this system and of a variation which requires no sensing. We have been able to characterize these systems and to prove that they can serve as parts feeding devices for planar polygonal parts. We present the planners for these systems and describe our implementations.
2142354
Mechanics, Planning, and Control for Tapping
We present analysis and experimental demonstration of manipulation by tapping. Our problem domain is positioning planar parts on a support surface by a sequence of taps; each tap imparts some initial velocities to the object, which then slides until it comes to rest due to friction. We formulate the mechanics of tapping for circular axisymmetric objects, show how to plan a single tap and a sequence of taps to reach a goal configuration, and present feedback control methods to robustly accomplish positioning tasks. With these methods, we have experimentally demonstrated positioning tasks using tapping, including high-precision positioning tasks in which the object is positioned more precisely than the tapping actuator. We show stability and sensitivity analysis in support of these results.
6649130
Cartop manipulation
This paper explores a novel mode of mobile manipulation using a car-like robot whose chassis does not extend above the height of its wheels. It transports an object that rests on top of the wheels, so as the robot moves forwards, the object moves forward relative to the robot. The robot must maneuver so that the object stays on top of the robot, or a second robot must be in position to receive the robot as it rolls off the first one. We describe the mechanics of this system, its basic maneuvers and manipulation techniques, present a motion planner for generating plans to transport an object, and give results of our experimental implementation of this system.
17487285
A tapping micropositioning cell
Describes the use of tapping actuators in a "micropositioning cell." Tapping actuators are fixed (both in position and orientation) about the perimeter of the cell. A part in the cell can be precisely positioned by firing a sequence of tapping actuators (sensing the position of the object after each tap for feedback control). Such a system could be used for micropositioning tasks or in parts feeding applications. We show the controllability of this system for circular parts, describe an algorithm to position these objects, and present the results of simulated experiments. We conclude with some future directions and address the issues in extending this work to more efficient algorithms that work on a broader class of parts.
18017218
Optimal line-sweep-based decompositions for coverage algorithms
Robotic coverage is the problem of moving a sensor or actuator over all points in given region. Ultimately, we want a coverage path that minimizes some cost such as time. We take the approach of decomposing the coverage region into subregions, selecting a sequence of those subregions, and then generating a path that covers each subregion in turn. We focus on generating decompositions based upon the planar line sweep. After a general overview of the coverage problem, we describe how our assumptions lead to the optimality criterion of minimizing the sum of subregion altitudes (which are measured relative to the sweep direction assigned to that subregion). For a line-sweep decomposition, the sweep direction is the same for all subregions. We describe how to find the optimal sweep direction for convex polygonal worlds. We then introduce the minimal sum of altitudes (MSA) decomposition in which we may assign a different sweep direction to each subregion. This decomposition is better for generating an optimal coverage path. We describe a method based on multiple line sweeps and dynamic programming to generate the MSA decomposition.
1537043
Topological Map Merging
When multiple robots cooperatively explore an environment, maps from individual robots must be merged to produce a single globally consistent map. This is a challenging problem when the robots do not have a common reference frame or global positioning. In this paper, we describe an algorithm for merging embedded topological maps. Topological maps provide a concise description of the navigability of an environment, and, with measurements easily collected during exploration, the vertices of the map can be embedded in a metric space. Our algorithm uses both the structure and the geometry of topological maps to determine the best correspondence between maps with single or multiple overlapping regions. Experiments with simulated and real-world data demonstrate the efficacy of our algorithm.
62135913
Kernel-based method for tracking objects with rotation and translation
This paper addresses the issue of tracking translation and rotation simultaneously. Starting with a kernel-based spatial-spectral model for object representation, we define an l/sub 2/-norm similarity measure between the target object and the observation, and derive a new formulation to the tracking of translational and rotational object. Based on the tracking formulation, an iterative procedure is proposed. We also develop an adaptive kernel model to cope with varying appearance. Experimental results are presented for both synthetic data and real-world traffic video.
62635072
Kernel autoassociator with applications to visual classification
Autoassociator is an important issue in concept learning, and the learned concept of a particular class can be used to distinguish the class from the others. For nonlinear autoassociation, This work presents a new model referred to as kernel autoassociator. Using kernel feature space as a potential nonlinear manifold, the model formulates the autoassociation as a special reconstruction problem from kernel feature space to input space. Two methods are developed to solve the problem. We evaluate the autoassociator with artificial data, and apply it to handwritten digit recognition and multiview face recognition, yielding positive experimental results.
11481204
Scheduling of MPI-2 one sided operations over InfiniBand
MPI-2 provides interfaces for one sided communication, which is becoming increasingly important in scientific applications. MPI-2 semantics provide the flexibility to reorder the one sided operations within an access epoch. Based on this flexibility, in this paper we try to improve the performance of one sided communication by scheduling one sided operations. We have come up with several re-ordering and aggregating schemes to achieve better network utilization. We have evaluated these schemes on both PCI-X and PCI-Express platforms. With re-ordering scheme, we see an improvement in the throughput up to 76%, latency up to 40%. With aggregation scheme, we observe an improvement of 44% and 42% for MPI/spl I.bar/Put and MPI/spl I.bar/Get latency respectively on PCI-Express platform.
40011370
Contextual Knowledge Representation, Retrieval and Interpretation in Multimedia e-Learning
In highly interactive modern multimedia e-learning environments, current e-learning support products based on basic information management technologies are not able to support semantic-based knowledge management and communication beyond heterogeneous multimedia learning resources. Much of desired intelligent e-learning functionality needs further research and technical developments with semantic context-awareness. Proposed framework in this paper is expected to improve the current isolated learning management status, by making the most use of related learning information, and enabling flexible knowledge retrieval, communication and transfer between instructors and learners. To work with related existing e-learning content description standards and enable a semantic-based interactive learning environment, this paper explores a set of novel contextual knowledge discovery and reuse techniques. Based on knowledge communication model analysis in university e-learning, a contextual knowledge representation model is presented. Corresponding knowledge retrieval and semantic knowledge interpretation techniques are presented afterwards towards supporting pedagogical learning approaches such as scenario-based learning.
17604511
POINT: a database for the prediction of protein-protein interactions based on the orthologous interactome
One possible path towards understanding the biological function of a target protein is through the discovery of how it interfaces within protein-protein interaction networks. The goal of this study was to create a virtual protein-protein interaction model using the concepts of orthologous conservation (or interologs) to elucidate the interacting networks of a particular target protein. POINT (the prediction of interactome database) is a functional database for the prediction of the human protein-protein interactome based on available orthologous interactome datasets. POINT integrates several publicly accessible databases, with emphasis placed on the extraction of a large quantity of mouse, fruit fly, worm and yeast protein-protein interactions datasets from the Database of Interacting Proteins (DIP), followed by conversion of them into a predicted human interactome. In addition, protein-protein interactions require both temporal synchronicity and precise spatial proximity. POINT therefore also incorporates correlated mRNA expression clusters obtained from cell cycle microarray databases and subcellular localization from Gene Ontology to further pinpoint the likelihood of biological relevance of each predicted interacting sets of protein partners.