SMARTech Community: College of Computing (CoC)

Towards Cosmopolitan Robots: Intelligent Navigation in Extended Man-Made Environments

Wed, 29 Oct 1986 22:58:59 GMT

Title: Towards Cosmopolitan Robots: Intelligent Navigation in Extended Man-Made Environments

Authors: Arkin, Ronald C.

Abstract: In the past, mobile robots have been constrained to operate in either an indoor or an outdoor environment, not both. Special purpose representations and ad hoc sensor techniques geared towards tasks of narrow focus have dominated these efforts. It is the purpose of this dissertation to lead towards the development of a more cosmopolitan robot; one whose domain of interaction is not as restricted as these previous attempts. The Autonomous Robot Architecture (AuRA) has been developed to meet these challenges. A "meadow" map, used for global path planning and containing embedded a priori knowledge to guide sensor expectations, serves as the robot's long term memory. A layered short term memory based on instantiated meadows represents the currently perceived world. A hierarchical path planner produces a global path free of collisions with all modeled obstacles. Schema theory is extended to include the mobile robot domain and serves as the principal theoretical framework. The schema-based path execution system handles unexpected and dynamic obstacles not present in the robot's world model. This motor schema-based navigation system produces reactive/reflexive behavior in direct response to sensor events. In addition, new techniques in the treatment of robot uncertainty which expedite sensory processing are presented. These include the use of a spatial error map with associated error growth and reduction techniques. Several computer vision sensor strategies have been developed for use within AuRA. These include a fast line-finding algorithm, a fast region segmentation algorithm, and a depth-from-motion algorithm. Experiments using our mobile vehicle HARV demonstrate the use of these vision algorithms for navigational purposes. Schema-based navigation using ultrasonic sensing is also demonstrated experimentally.

Integrated Mission Specification and Task Allocation for Robot Teams - Part 2: Testing and Evaluation

Sat, 29 Oct 2005 22:58:59 GMT

Title: Integrated Mission Specification and Task Allocation for Robot Teams - Part 2: Testing and Evaluation

Authors: Arkin, Ronald C.; Endo, Yochiro; Ulam, Patrick D.; Wagner, Alan

Abstract: This work presents the evaluation of two mission specification and task allocation architectures. These architectures, described in part 1 of this paper, present novel means with which to integrate a case-based reasoning (CBR) mission planner with contract net protocol (CNP) based task allocation. In the first design, the CBR and runtime-CNP architecture, the case-based mission planner generates mission plans that support necessary behaviors for CNP-based task allocation and execution. In the second design, the CBR and premission-CNP architecture, task allocation takes place during mission specification. The results of an empirical evaluation of the CBR and runtime-CNP across three naval scenarios is described. Finally, we briefly describe an earlier usability evaluation of the CBR and premission-CNP architecture using goals, operators, methods, and selection rules modeling.

Integrated Mission Specification and Task Allocation for Robot Teams - Design and Implementation

Sat, 29 Oct 2005 22:58:59 GMT

Title: Integrated Mission Specification and Task Allocation for Robot Teams - Design and Implementation

Authors: Arkin, Ronald C.; Endo, Yochiro; Ulam, Patrick D.; Wagner, Alan

Abstract: As the capabilities, range of missions, and the size of robot teams increase, the ability for a human operator to account for all the factors in these complex scenarios can become exceedingly difficult. Our previous research has studied the use of case-based reasoning (CBR) tools to assist a user in the generation of multi-robot missions. These tools, however, typically assume that the robots available for the mission are of the same type (i.e., homogeneous). We loosen this assumption through the integration of contract-net protocol (CNP) based task allocation coupled with a CBR-based mission specification wizard. Two alternative designs are explored for combining case-based mission specification and CNP-based team allocation as well as the tradeoffs that result from the selection of one of these approaches over the other.

Adaptive Teams of Autonomous Aerial and Ground Robots for Situational Awareness

Sun, 29 Oct 2006 22:58:59 GMT

Title: Adaptive Teams of Autonomous Aerial and Ground Robots for Situational Awareness

Authors: Arkin, Ronald C.; Endo, Yoichiro; Chaimowicz, Luiz; Cowley, Anthony; Grocholsky, Ben; Hsieh, Mong-ying A.; Jung, Boyoon; Keller, James F.; Kumar, Vijay; MacKenzie, Douglas Christopher; Sukhatme, Gaurav S.; Taylor, Camillo J.; Wolf, Denis F.

Abstract: In this paper, we report on the integration challenges of the various component technologies developed towards the establishment of a framework for deploying an adaptive system of heterogeneous robots for urban surveillance. In our integrated experiment and demonstration, aerial robots generate maps that are used to design navigation controllers and plan missions for the team. A team of ground robots constructs a radio signal strength map that is used as an aid for planning missions. Multiple robots establish a mobile, ad-hoc communication network that is aware of the radio signal strength between nodes and can adapt to changing conditions to maintain connectivity. Finally, the team of aerial and ground robots is able to monitor a small village, and search for and localize human targets by the color of the uniform, while ensuring that the information from the team is available to a remotely located human operator. The key component technologies and contributions include (a) mission speci cation and planning software; (b) exploration and mapping of radio signal strengths in an urban environment; (c) programming abstractions and composition of controllers for multi-robot deployment; (d) cooperative control strategies for search, identi cation, and localization of targets; and (e) three-dimensional mapping in an urban setting.

Description: This is a preprint of an article accepted for publication in the Journal of Field Robotics, copyright 2007. Journal of Field Robotics 24(11), 991–1014 (2007) © 2007 Wiley Periodicals, Inc. Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/rob.202222