@STRING{aaai = {American Association for Artificial Intelligence} } @STRING{aaai-94 = {Proc.\ 12th Nat. Conf.\ on Artificial Intelligence} } @STRING{aaai-addr={Menlo Park, CA} } @STRING{acad = {Academic Press} } @STRING{acad-addr={San Diego; London} } @STRING{add = {Addison-Wesley} } @STRING{add-addr= {Reading, MA} } @STRING{air = {{AI} Review} } @STRING{algo = {Algorithmica} } @STRING{bj = {Biophysical Journal} } @STRING{bp = {Biopolymers} } @STRING{cagd = {Computer Aided Geometric Design} } @STRING{cam = {Cambridge University Press} } @STRING{cam-addr= {Cambridge, UK; New York; Melbourne} } @STRING{cdc = {Conf.\ on Decision \& Control} } @STRING{cdc-01 = {Proc.\ 40th Conf.\ on Decision \& Control} } @STRING{cdc-91 = {Proc.\ 30th Conf.\ on Decision \& Control} } @STRING{cdc-95 = {Proc.\ 34th Conf.\ on Decision \& Control} } @STRING{cg = {Computer Graphics} } @STRING{cgta = {Computational Geometry: Theory and Applications} } @STRING{cpd = {Current Pharmaceutical Design} } @STRING{csm = {{IEEE} Control Systems Magazine} } @STRING{ec = {Engineering with Computers} } @STRING{else = {Elsevier} } @STRING{else-addr={New York} } @STRING{icra = {{IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-00 = {Proc.\ 2000 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-01 = {Proc.\ 2001 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-02 = {Proc.\ 2002 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-03 = {Proc.\ 2003 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-04 = {Proc.\ 2004 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-05 = {Proc.\ 2005 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-06 = {Proc.\ 2006 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-84 = {Proc.\ 1984 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-85 = {Proc.\ 1985 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-87 = {Proc.\ 1986 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-88 = {Proc.\ 1988 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-89 = {Proc.\ 1989 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-90 = {Proc.\ 1990 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-91 = {Proc.\ 1991 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-92 = {Proc.\ 1992 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-93 = {Proc.\ 1993 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-94 = {Proc.\ 1994 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-95 = {Proc.\ 1995 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-96 = {Proc.\ 1996 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-97 = {Proc.\ 1997 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-98 = {Proc.\ 1998 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{icra-99 = {Proc.\ 1999 {IEEE} Intl.\ Conf.\ on Robotics and Automation} } @STRING{ieee = {IEEE} } @STRING{ieee-addr={Piscataway, NJ} } @STRING{ijc = {Intl.\ J.\ of Control} } @STRING{ijcga = {Intl.\ J.\ of Computational Geometry and Applications} } @STRING{ijnme = {Intl.\ J.\ of Numerical Methods in Engineering} } @STRING{ijrr = {Intl.\ J.\ of Robotics Research} } @STRING{iros = {{IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-00 = {Proc.\ 2000 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-01 = {Proc.\ 2001 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-02 = {Proc.\ 2002 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-03 = {Proc.\ 2003 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-04 = {Proc.\ 2004 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-05 = {Proc.\ 2005 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-06 = {Proc.\ 2006 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-07 = {Proc.\ 2006 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-92 = {Proc.\ 1992 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-93 = {Proc.\ 1993 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-94 = {Proc.\ 1994 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-95 = {Proc.\ 1995 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-97 = {Proc.\ 1997 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-98 = {Proc.\ 1998 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iros-99 = {Proc.\ 1999 {IEEE/RSJ} Intl.\ Conf.\ on Intelligent Robots and Systems} } @STRING{iser-99 = {Experimental Robotics {VI}} } @STRING{isrr = {Intl.\ Symp.\ on Robotics Research} } @STRING{jacm = {Journal of the ACM} } @STRING{jam = {{ASME} Journal of Applied Mechanics} } @STRING{jcamd = {Journal of Computer-Aided Molecular Design} } @STRING{jcb = {J.\ Comp.\ Bio.} } @STRING{jcc = {J.\ Comp.\ Chemistry} } @STRING{jco = {{SIAM} J.\ of Control and Optimization} } @STRING{jcp = {J.\ Chem.\ Physics} } @STRING{jdsmc = {J.\ of Dynamic Systems, Measurement, and Control} } @STRING{jmb = {J.\ of Molec.\ Bio.} } @STRING{jmc = {Journal of Medicinal Chemistry} } @STRING{jmgm = {Journal of Molecular Graphics and Modelling} } @STRING{jpca = {Journal of Physical Chemistry A} } @STRING{jpcb = {Journal of Physical Chemistry B} } @STRING{jra = {{IEEE} J.\ of Robotics and Automation} } @STRING{kauf = {Morgan Kaufmann} } @STRING{kauf-addr={San Mateo, CA} } @STRING{klu = {Kluwer} } @STRING{klu-addr= {Dordrecht; Boston} } @STRING{lea = {Erlbaum} } @STRING{lea-addr= {Hillsdale, NJ} } @STRING{mcg = {McGraw-Hill} } @STRING{mit = {MIT Press} } @STRING{mit-addr= {Cambridge, MA} } @STRING{north = {North-Holland} } @STRING{north-addr={Amsterdam; New York} } @STRING{oxf = {Oxford University Press} } @STRING{oxf-addr= {Oxford, UK; New York} } @STRING{pami = {{IEEE} Trans.\ on Pattern Analysis and Machine Intelligence} } @STRING{pcc = {PhysChemComm} } @STRING{pddd = {Perspectives in Drug Discovery and Design} } @STRING{pnas = {Proc.\ Natl.\ Acad.\ of Science USA} } @STRING{pra = {Physical Review A} } @STRING{pren = {Prentice-Hall} } @STRING{pren-addr={Englewood Cliffs, NJ} } @STRING{ps = {Protein Science} } @STRING{psfb = {Proteins} } @STRING{psfg = {Proteins} } @STRING{ras = {Robotics and Autonomous Systems} } @STRING{scg = {Symposium on Computational Geometry} } @STRING{sjc = {{SIAM} J.\ Comput.} } @STRING{smc = {{IEEE} Trans.\ on Systems, Man, and Cybernetics} } @STRING{spr = {Springer Verlag} } @STRING{spr-addr= {Berlin; Heidelberg; New York} } @STRING{struc = {Structure} } @STRING{tac = {{IEEE} Trans.\ on Automatic Control} } @STRING{tim = {{IEEE} Trans.\ on Instrumentation and Measurement} } @STRING{tog = {{ACM} Trans.\ on Graphics} } @STRING{toms = {{ACM} Trans.\ on Mathematical Software} } @STRING{tra = {{IEEE} Trans.\ on Robotics and Automation} } @STRING{tro = {{IEEE} Trans.\ on Robotics} } @STRING{wafr = {Workshop on the Algorithmic Foundations of Robotics} } @STRING{wil = {John Wiley \& Sons} } @STRING{wil-addr= {New York} } @STRING{zamm = {Zeitschrift f{\"u}r Angewandte Mathematik und Mechanik} } @InCollection{ salemi2006autonomous-discovery-and-functional-response, author = {Behnam Salemi and Peter Will and Wei-Min Shen}, bib2html_pubtype={Book Chapters}, booktitle = {Complex Engineering Systems: Science Meets Technology}, editor = {Dan Braha and Ali A. Minai and Yaneer Bar-Yam}, pages = {364--384}, publisher = spr, title = {Autonomous Discovery and Functional Response to Topology Change in Self-Reconfigurable Robots}, year = {2006} } @InProceedings{ chiu2006concurrent-and-real-time-task-management, abstract = {We present a concurrent and real-time task management method for distributed control of modules in a self-reconfigurable robot. This method is essential for modules to simultaneously control multiple behaviours in real-time and supporting a concurrent programming style that will greatly ease the development of control software for large-scale reconfigurable robots. Although real-time operating systems and concurrent programming have been around for many years, it is only recently that the technology is miniaturized enough for embedded systems and self-reconfigurable robots. We have successfully implemented the method on our new SuperBot modules and have demonstrated its utility through the programming of locomotion gaits with the real modules.}, author = {Harris Chi Ho Chiu and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = {Proc.\ Third Intl.\ Conf.\ on Autonomous Robots and Agents}, title = {Concurrent and Real-Time Task Management for Self-Reconfigurable Robots}, year = {2006} } @InProceedings{ suri2006system-design-of-robots-for-application, abstract = {This paper presents the design of an experimental system for assembly applications in space. The prototypical application is the assembly of mechanical trusses. The system used an air-hockey table to simulate a frictionless two-dimensional space. Assembly robots fly on the surface finding, gathering and assembling the relevant parts to perform the construction. The system design involved building the FIMER Robots, the test bed, the sensing system for position and velocity feedback and the control scheme. This paper describes the hardware and software used in the various sub-systems and includes calibrations and measurements and the results of experiments.}, address = {Beijing, China}, author = {Harshit Suri and Peter Will and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-06, month = oct, title = {System Design of Robots for Application to In-Space Assembly}, year = {2006} } @InProceedings{ everist2006transformation-of-control-in-congruent-self-reconfigurable, abstract = {Much work on self-reconfigurable robotics has been focused on motion planning and physical reconfiguration of the robot. Using the Superbot self-reconfigurable robot, we focus on the details of realizing locomotion gaits given that a single robot topology can be realized in a large number of different ways. That is, each module in the robot topology has 4 symmetric orientations that are functional and shape equivalent. Once a role is selected for each module, such as through the use of hormone-inspired control, each module's role is supplied with a gait template which then must be transformed to suit the local configurations of each module with respect to the global topology. We provide a theoretical framework for which this can be accomplished. }, address = {Beijing, China}, author = {Jacob Everist and Feili Hou and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-06, month = oct, title = {Transformation of Control in Congruent Self-Reconfigurable Robot Topologies}, year = {2006} } @InProceedings{ damer2005design-simulation-of-lunar-exploration, author = {B. Damer and D. Rasmussen and P. Newman and B. Blair and M. Duke and R. King and T. Muff and M. Shirley and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = {Lunar Exploration Analysis Group (LEAG)}, title = {Design Simulation of Lunar Exploration and {ISRU} Prototype Vehicles and Mission Scenarios}, url = {http://www.lpi.usra.edu/meetings/leag2005/}, year = {2005} } @InProceedings{ lawrence2005superbots-on-the-lunar-surface:-a-habitat, author = {S. J. Lawrence and G. J. Taylor and R. C. F. Lentz and L. M. Martel and Wei-Min Shen and Peter M. Will and M. H. Sims and S. Colombano and D. Kortenkamp and B. Damer and W. Chun}, bib2html_pubtype={Conference Papers}, booktitle = {Lunar Exploration Analysis Group (LEAG)}, title = {{SuperBots} on the Lunar Surface: A Habitat Operations and Maintenance System {(HOMS)}}, url = {http://www.lpi.usra.edu/meetings/leag2005/}, year = {2005} } @InProceedings{ taylor2005superbots-on-the-lunar-surface:-mini-mobile, author = {G. J. Taylor and R. C. F. Lentz and S. J. Lawrence and L. M. Martel and Wei-Min Shen and Peter M. Will and M. H. Sims and S. Colombano and D. Kortenkamp and B. Damer and W. Chun}, bib2html_pubtype={Conference Papers}, booktitle = {Lunar Exploration Analysis Group (LEAG)}, title = {{SuperBots} on the Lunar Surface: Mini-Mobile Investigation System ({Mini-MIS})}, url = {http://www.lpi.usra.edu/meetings/leag2005/}, year = {2005} } @InProceedings{ shen2005superbots:-modular-multifunctional-reconfigurable, author = {Wei-Min Shen and J. Bogdanowicz and W. Chun and M. Yim and Peter M. Will and M. Sims and S. Colombano and D. Kortenkamp and S. Vanderzyl and E. Baumgartner and J. Taylor}, bib2html_pubtype={Conference Papers}, booktitle = {Lunar Exploration Analysis Group (LEAG)}, title = {{SuperBots}: Modular, Multifunctional, Reconfigurable Robotic System for Space Exploration}, url = {http://www.lpi.usra.edu/meetings/leag2005/}, year = {2005} } @InProceedings{ lentz2005superbots-on-the-lunar-surface:-a-robotic, author = {R. C. F. Lentz and G. J. Taylor and S. J. Lawrence and L. M. Martel and Wei-Min Shen and Peter M. Will and M. H. Sims and S. Colombano and D. Kortenkamp and B. Damer and W. Chun}, bib2html_pubtype={Conference Papers}, booktitle = {Lunar Exploration Analysis Group (LEAG)}, title = {{SuperBots} on the Lunar Surface: A Robotic Multi-Use Lunar Explorer {(MULE)}}, url = {http://www.lpi.usra.edu/meetings/leag2005/}, year = {2005} } @InProceedings{ shen2006multimode-locomotion-via-superbot-robots, abstract = {This paper presents a modular and reconfigurable robot for multiple locomotion modes based on reconfigurable modules. Each mode consists of characteristics for the environment type, speed, turning-ability, energy-efficiency, and recoverability from failures. The paper demonstrates this solution by the Superbot robot that combines advantages from MTRAN, CONRO and others. Experimental results, both in real robots and in simulation, have shown the validity of the approach and demonstrated the movements of forward, backward, turn, sidewinder, maneuver, and travel on batteries up to 500 meters on a flat terrain. In physics-based simulation, Superbot can perform as snake, caterpillar, insect, spider, rolling track, Hwalker, etc., and move 1.0 meter/second on flat terrain with less than 6W/module, and climb slopes of no less 40 degrees.}, address = {Orlando, FL}, author = {Wei-Min Shen and Maks Krivokon and Harris Chiu and Jacob Everist and Michael Rubenstein and Jagadesh Venkatesh}, bib2html_pubtype={Conference Papers}, booktitle = icra-06, pages = {2552--2557}, title = {Multimode Locomotion via {SuperBot} Robots}, year = {2006} } @InProceedings{ will1999robot-modularity-for-self-reconfiguration, address = {Boston, MA}, author = {Peter Will and Andres Castano and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = {Proc. SPIE Sensor Fusion and Decentralized Control II}, pages = {236-245}, title = {Robot Modularity for Self-Reconfiguration}, year = {1999} } @InProceedings{ castano2000autonomous-and-self-sufficient-conro-modules, address = {Knoxville, TN}, author = {Andres Castano and R. Chokkalingam and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {Proc. 5th Int'l Symp. Distributed Autonomous Robotic Systems}, pages = {155--164}, publisher = {Springer-Verlag}, title = {Autonomous and Self-Sufficient {CONRO} Modules for Reconfigurable Robots}, year = {2000} } @InProceedings{ castano2000mechanical-design-of-a-module-for-autonomous, abstract = {The goal of the Conro project is to build deployable self-reconfigurable robots, i.e., small homogeneous modular robots that can be reconfigured into different shapes such as snakes or hexapods. In this paper we describe the mechanical design of the first generation of Conro modules: the philosophy of their design, their parts and functionality and derive two inequalities that relate the design parameters of a module. Each module is fully self-contained in every sense; it carries its own CPU, power supply, and actuators. The modules were designed to work in groups, as robots, and thus, they also support inter-module communication. We conclude the paper describing a Conro hexapod as an example of the robots that can be built using these modules.}, author = {Andres Castano and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = iros-00, pages = {2203--2209}, title = {Mechanical Design of a Module for Autonomous Reconfigurable Robots}, year = {2000} } @InProceedings{ khoshnevis2001reconnectable-joints-for-self-reconfigurable-robots, abstract = {Self-reconfigurable robots are modular robots that can dynamically and intelligently reconfigure their shape and size to accomplish difficult missions. To build such robots, however, a number of technical challenges must be overcome. One critical problem is the design and implementation of the reconnectable joints (also called connectors), which allows modules to autonomously connect and disconnect from one another. Such a mechanism must be power efficient, reliable, and compact (the mechanism must fit into a tight space). This paper gives an overview of the CONRO self-reconfigurable robots, and focuses on the reconnectable joints of the CONRO modules. The paper identifies a set of desired features and operation constraints for the joints, and describes our current design for the connectors.}, author = {Behrokh Khoshnevis and R. Kovac and Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = iros-01, pages = {584--589}, title = {Reconnectable Joints for Self-Reconfigurable Robots}, year = {2001} } @InProceedings{ stoy2002on-the-use-of-sensors-in-self-reconfigurable-robots, abstract = {In this paper we investigate the use of sensors in self-reconfigurable robots. We review several physically realized self-reconfigurable robots and conclude that little attention has been paid to the use of sensors. This is unfortunate since sensors can provide essential feedback that can be used to guide self-reconfiguration and control. In the systems that do use sensor feedback, the feedback is used locally on each module. However we identify a need in some situations to use sensor feedback globally. We therefore propose an approach where raw sensor values are abstracted and propagated to all modules. The sensor values are abstracted differently depending on the position of the producing sensor on the robot. We combine this approach with role based control, a control method for self-reconfigurable robots that we have developed earlier. We demonstrate that by combing these two approaches it is possible to make a self-reconfigurable robot consisting of six modules walk and avoid obstacles. However the reaction time of the robot is slow and therefore we discus possible ways of reducing the reaction time.}, address = {Edinburgh, UK}, author = {Kasper St{\o}y and Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {Proc.\ 7th Intl.\ Conf.\ on Simulation of Adaptive Behavior (SAB02)}, month = aug, pages = {48--57}, title = {On the Use of Sensors in Self-Reconfigurable Robots}, year = {2002} } @InProceedings{ shen2002distributed-and-dynamic-task-reallocations, abstract = {Task reallocation in a multi-robot organization is a process that distributes a decomposed global task to individual robots. This process must be distributed and dynamic because it relies on critical information that can only be obtained during mission execution. The paper presents a representation for this challenging problem and proposes an algorithm that allows member robots to trade tasks and responsibilities autonomously. Preliminary results show that such an algorithm can indeed improve the efficiency of organizational performance and construct a locally optimal (hill climbing) task allocation during mission execution.}, address = {Washington, DC}, author = {Wei-Min Shen and Behnam Salemi}, bib2html_pubtype={Conference Papers}, booktitle = icra-02, month = may, pages = {1019--1024}, title = {Distributed and Dynamic Task Reallocations in Robot Organization}, year = {2002} } @InCollection{ shen2002simulating-self-organization-with-the-digital, author = {Wei-Min Shen and C.-M. Chuong}, bib2html_pubtype={Book Chapters}, booktitle = {Multi-Robot Systems: From Swarms to Intelligent Automata}, editor = {A. Schultz and L. Parker}, pages = {149--160}, publisher = klu, title = {Simulating self-organization with the Digital Hormone Model}, year = {2002} } @InProceedings{ shen2002simulating-self-organization-for-multi-robot-systems, abstract = {How do multiple robots self-organize into global patterns based on local communications and interactions? This paper describes a theoretical and simulation model called ``Digital Hormone Model'' (DHM) for such a self-organization task. The model is inspired by two facts: complex biological patterns are results of self-organization of homogenous cells regulated by hormone-like chemical signals, and distributed controls can enable self-reconfigurable robots to performance locomotion and reconfiguration. The DHM is an integration and generalization of reaction-diffusion model and stochastic cellular automata. The movements of robots (or cells) in DHM are computed not by the Turing's differential equations, nor the Metropolis rule, but by stochastic rules that are based on the concentration of hormones in the neighboring space. Experimental results have shown that this model can produce results that match and predict the actual findings in the biological experiments of feather bud formation among uniform skin cells. Furthermore, an extension of this model may be directly applicable to self-organization in multirobot systems using simulated hormone-like signals. }, address = {Switzerland}, author = {Wei-Min Shen and C.-M. Chuong and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = iros-02, pages = {2776--2781}, title = {Simulating Self-Organization for Multi-Robot Systems}, year = {2002} } @InProceedings{ shen2002digital-hormone-models-for-self-organization, address = {Sydney, Australia}, author = {Wei-Min Shen and C.-M. Chuong and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {Artificial Life VIII, Intl.\ Conf.\ on Simulation and Synthesis of Living Systems}, month = dec, title = {Digital Hormone Models for Self-Organization}, url = {http://www.alife.org/alife8/}, year = {2002} } @InProceedings{ shen2002self-reconfigurable-robots-for-robosphere, address = {NASA Ames Research Center}, author = {Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {The RoboSphere Workshop}, title = {Self-Reconfigurable Robots for {ROBOSPHERE}}, year = {2002} } @InProceedings{ khoshnevis2003highly-compliant-and-self-tightening-docking, abstract = {This paper describes a new docking system, called Compliant-And-Self-Tightening (CAST), developed as an effective and efficient connector for joining and releasing modules of self-reconfigurable or metamorphic robotic systems. CAST has been successfully implemented in CONRO where its highly compliant and passive features have allowed a considerable ease of execution of a variety of docking algorithms, while using no additional energy for docking and negligible amount of energy for undocking. Development of CAST was motivated by observing the difficulty of implementation of an earlier less compliant docking system designed by the authors for CONRO.}, address = {Taiwan}, author = {Behrokh Khoshnevis and Peter Will and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = icra-03, pages = {2311--2316}, title = {Highly Compliant and Self-Tightening Docking Modules for Precise and Fast Connection of Self-Reconfigurable Robots}, year = {2003} } @InProceedings{ stoy2003implementing-configuration-dependent-gaits, abstract = {In this paper we examine locomotion in the context of self-reconfigurable robots. Self-reconfigurable robots are robots built from many connected modules. A self-reconfigurable robot can change its shape and configuration by changing the way these modules are connected. The focus of this paper is to understand how several locomotion gaits can be represented in such a robot and how the robot can select one of these gaits depending on its configuration. We implement a control system based on role based control in a physical self-reconfigurable robot built from seven modules. In several experiments we successfully demonstrate that when the robot is manually reconfigured from a chain to a quadruped configuration the robot changes gait from a sidewinder snake gait to a quadruped walking gait. We conclude that role based control is a promising central method for controlling locomotion of self-reconfigurable robots.}, address = {Taiwan}, author = {Kasper St{\o}y and Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = icra-03, pages = {3828--3833}, title = {Implementing Configuration Dependent Gaits in a Self-Reconfigurable Robot}, year = {2003} } @InProceedings{ shen2003self-assembly-in-space-via-self-reconfigurable-robots, abstract = {Self-assembly systems in space are arguably within the reach of today's technology based on the research and development of self-reconfigurable robots on earth. This paper presents an approach to self-assembly in space by developing: (1) a novel design for intelligent and reconfigurable components; (2) the free-flying ``intelligent fiber/rope'' ``match-maker'' robots with self-reconfigurable and self-adjustable tethering for autonomous docking; and (3) a totally distributed control method for planning, executing, and monitoring the assembly process. These approaches are partially evaluated by a set of experimental and simulation results to simulate the dynamics and control of free-flying objects in zero-gravity environment.}, address = {Taiwan}, author = {Wei-Min Shen and Peter Will and Behrokh Khoshnevis}, bib2html_pubtype={Conference Papers}, booktitle = icra-03, month = sep, pages = {2516--2521}, title = {Self-Assembly in Space via Self-Reconfigurable Robots}, year = {2003} } @InProceedings{ salemi2004distributed-behavior-collaboration-for-self-reconfigurable, abstract = {This paper describes a distributed and decentralized approach for modules in a self-reconfigurable robot to select appropriate behaviors based on four factors: the current global task, the local topological location in the current configuration, the local state/sensor information, and the received messages from their neighbors. This approach does not assume any unique global identifiers for the modules, and is robust for reconfigurations of modules. The approach is enabled by the extended neighbor topology built upon a previous local topology representation and a hormone-inspired communication and control protocols. Experimental results on the CONRO robot have shown some unique features of this approach for the control of self-reconfigurable robots in general.}, address = {New Orleans, USA}, author = {Behnam Salemi and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = icra-04, month = {April/May}, pages = {4178--4183}, title = {Distributed Behavior Collaboration for Self-Reconfigurable Robots}, year = {2004} } @InProceedings{ rubenstein2004docking-among-independent-and-autonomous, abstract = {Docking between independent groups of self-reconfigurable robotic modules enables the merger of two or more independent self-reconfigurable robots. This ability allows independent reconfigurable robots in the same environment to join together to complete a task that would otherwise not be possible with the individual robots prior to merging. The challenges for this task include: (1) coordinate and align two independent self-reconfigurable robots using the docking guidance system available only at the connectors of the docking modules; (2) overcome the inevitable errors in the alignment by a novel and coordinated movements from both docking ends; (3) ensure the secure connection at the end of docking; (4) switch configuration and let modules to discover the changes and new connections so that the two docked robots will move as a single coherent robot. We have developed methods for overcome these challenging problems and accomplished for the first time an actual docking between two independent CONRO robots each with multiple modules.}, address = {New Orleans, USA}, author = {Michael Rubenstein and Kenneth Payne and Peter Will and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = icra-04, month = {April/May}, pages = {2877--2882}, title = {Docking among Independent and Autonomous {CONRO} Self-Reconfigurable Robots}, year = {2004} } @InProceedings{ salemi2004autonomous-discovery-and-functional-response, abstract = {The topology of a self-reconfigurable robot can change at anytime. This can be as a result of the failure of some modules of the robot, joining new modules to the robot, displacement of some modules from one location to another caused by the self-reconfiguration task or any combination of these cases. Considering that the process of selecting relevant behaviors to accomplish a given task is based on the current topology of the self-reconfigurable robot, modules must be able to detect and respond to any changes to the robot topology. When changes to the topology of the robot are detected, modules can investigate new ways of accomplishing the given task. This paper presents a distributed solution, FEATURE algorithm, to the problem of autonomous discovery and functional response to topology change. The result is experimentally verified and demonstrated on the CONRO self-reconfigurable robots.}, address = {Sendai, Japan}, author = {Behnam Salemi and Peter Will and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-04, pages = {2667--2672}, title = {Autonomous Discovery and Functional Response to Topology Change in Self-Reconfigurable Robots}, year = {2004} } @InProceedings{ payne2004sensor-based-distributed-control-for-chain-typed, abstract = {This paper describes two contributions for chain typed self-reconfigurable robots: a very illustrative self-reconfiguration task changing from ``I'' shape to ``T'' shape, and a sensor-based distributed control method for automatic planning and execution of self-reconfiguration. In the ``I-to-T'' task, a snake robot is to reconfigure itself into a tripod by docking the tail to a target module in the body, releasing a portion of the connected mass as a new leg, and switching to a new gait automatically. We first accomplished this task using predetermined instructions for individual modules without considering sensor inputs. We then developed a sensor-based approach using our hormone-inspired distributed control to allow the robot to dynamically accept the point of connection at run-time, align the tail and the target using sensors, and select appropriate actions based on modules' location in the configuration. Compared to the standard inverse kinematics, this new control approach is sensor-based and can endure the limited computational resources and uncertainties in the connections. It can be applied to self-reconfigurations that are not designed by the programmers but triggered by the environment.}, address = {Sendai, Japan}, author = {Kenneth Payne and Behnam Salemi and Peter Will and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-04, month = {Sept./Oct.}, pages = {2074--2080}, title = {Sensor-Based Distributed Control for Chain-Typed Self-Reconfiguration}, year = {2004} } @InProceedings{ everist2004a-system-for-in-space-assembly, abstract = {Abstract- This paper presents an experimental system for assembly in space. A weightless and frictionless environment is approximated using an air-hockey table where robots and structural components can noat on the surface. The robots use fan propulsion lo dock with components and assemble them together to make 2D struelures This system is designed to implement three key technologies for space self-assembly: 1) intelligent components with universal mnnectors, 2) a set of sell-reconfigurable robots that fetch and assemble components, and 3) a distributed method for controlling the robotic-assembly pmeess. An overview of the system's design and experimental results is presented.}, address = {Sendai, Japan}, author = {Jacob Everist and K. Mogharei and H. Suri and N. Ranasinghe and Behrokh Khoshnevis and Peter Will and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-04, month = {Sept./Oct.}, pages = {2356--2361}, title = {A System for In-Space Assembly}, year = {2004} } @InProceedings{ rubenstein2004robotic-enzyme-based-autonomous-self-replication, abstract = {In this paper, we introduce and describe the notion of a robotic enzyme, and how it can use properties that are similar to biological enzymes to autonomously self-replicate. We test the idea of robotic enzymes using a virtual environment that simulates the currently existing modular robots in a physically accurate way. We describe the self-replicating features of robotic enzymes, and how they could be used to autonomously self-replicate for multiple generations, limited only by the amount of modules in the environment.}, address = {Sendai, Japan}, author = {Michael Rubenstein and Maks Krivokon and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-04, pages = {2661--2666}, title = {Robotic Enzyme-Based Autonomous Self-Replication}, year = {2004} } @InProceedings{ salemi2005milo-personal-robot-platform, abstract = {Recent advances in mobile robotic technology has given rise to new types of robotic applications called Personal Robotics. The main feature of these applications is that they require low cost robots that involve assisting people in doing their everyday jobs such as providing personal assistance, commercial security, mobile tele-conferencing, tele-presence, home services, entertainment, and elderly care. In this paper we will introduce a low cost and general purpose mobile robotic platform called MILO. It offers unique hardware and software features which make MILO suitable for a wide spectrum of personal robotic applications. MILO possesses PC architecture and runs on Windows XP. We have experimentally evaluated MILO's performance. Preliminary results show that MILO can be effectively used to develop personal robotic applications. }, address = {Edmonton, Canada}, author = {Behnam Salemi and J. Reis and A. Saifhashemi and F. Nikgohar}, bib2html_pubtype={Conference Papers}, booktitle = iros-05, pages = {4089--4094}, title = {{MILO}: Personal Robot Platform}, year = {2005} } @InProceedings{ payne2006single-sensor-probabilistic-localization-on-the-seres, abstract = {This paper proposes a novel method for localizing a stationary infrared source of unknown orientation relative to a static docking sensor. This method uses elliptical approximations of likely positions of the infrared source and computes the intersections to find the most probable locations. It takes only a few samples to localize, is easily computed with inexpensive microcontrollers, and is robust to sensor noise. We then compare our approach with two other methods. The first uses a Bayesian filter across a map of discrete locations in the robot's operational workspace to determine the suspected source position. The second also uses a probability distribution map but uses the method described by Elfes in his paper on probabilistic sonar-based mapping and navigation [1]. We show that our approach localizes quickly with a single sensor and is no more computationally demanding than other methods. }, address = {Tokyo, Japan}, author = {Kenneth Payne and Jacob Everist and Feili Hou and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = {The 9th Intl.\ Conf.\ Intelligent and Autonomous Systems (IAS-9)}, month = {March}, title = {Single-Sensor Probabilistic Localization on the {SeReS} Self-Reconfigurable Robot}, year = {2006} } @InProceedings{ hou2006hormone-inspired-adaptive-distributed-synchronization, abstract = { In this paper, we present a hormone-inspired adaptive distributed synchronization of reconfiguration robots. The main approach is to use a combination of discrete event-driven hormone communication and continuous time-controlled motor motion. Without any prior knowledge, all the modules' speed can be self-adjusted to adapt to each other to achieve a collaborative motion. Simulation and experimental results show that our method is robust to accuracy of local timer, configuration change and unexpected disturbance. }, address = {Tokyo, Japan}, author = {Feili Hou and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = {The 9th Intl.\ Conf.\ Intelligent and Autonomous Systems (IAS-9)}, month = {March}, title = {Hormone-inspired Adaptive Distributed Synchronization of Reconfigurable Robots}, year = {2006} } @InProceedings{ hou2006mathematical-foundation-for-hormone-inspired-control, abstract = {In this paper, we present a general mathematical foundation of hormone-inspired control for the self-reconfigurable robotic system. Problem considered here is the lack of a mathematical description to analyze and explain the dynamic behavior of self-reconfigurable robots. In the global level, the idea of virtual disconnection is developed to abstract the low level module control away from the high level synchronization for both cyclic and acyclic robot configuration. In the module layer, the linear space model is developed to describe each module's internal state, input-output hormone transformation, and its action selection. As a combination of hormone and modern control theory, the approach in this paper gives more features, such as predictability and stability analysis etc, to hormone-inspired control, and makes it applicable to self-reconfigurable systems in general. Simulation and experimental results show the capacity of our method.}, address = {Orlando, FL}, author = {Feili Hou and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = icra-06, month = may, pages = {1477--1482}, title = {Mathematical Foundation for Hormone-Inspired Control for Self-Reconfigurable Robotic Systems}, year = {2006} } @InProceedings{ shen2000hormone-based-control-for-self-reconfigurable-robots, abstract = {Self-reconfigurable or metamorphic robots can change their individual and collective shape and size to meet operational demands. Since these robots are constructed from a set of autonomous and connectable modules (or agents), controlling them is a challenging task. The difficulties stem from the facts that all locomotion, perception, and decision making must be distributed among a network of modules, that this network has a dynamic topology, that each individual module has only limited resources, and that the coordination between modules is highly complex and diverse. To meet these challenges, this paper presents a distributed control mechanism inspired by the concept of hormones in biological systems. We view hormones as special messages that can trigger different actions in different modules, and we exploit such properties to coordinate motions and perform reconfiguration in the context of limited communications and dynamic network topologies. The paper develops a primitive theory of hormone-based control, reports the experimental results of applying such a control mechanism to our CONRO metamorphic robots, and discusses the generality of the approach for a larger class of distributed autonomous systems.}, address = {Barcelona, Spain}, author = {Wei-Min Shen and Yimin Lu and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {Proc. Intl. Conf. on Autonomous Agents}, title = {Hormone-Based Control for Self-Reconfigurable Robots}, year = {2000} } @InProceedings{ shen2000hormones-for-self-reconfigurable-robots, abstract = {Self-reconfigurable, or metamorphic, robots can change their individual and collective shape and size to meet operational demands. Since these robots are constructed from a set of autonomous and connectable modules (or agents), control of the robots and coordination among the modules are highly complex and challenging tasks. The difficulties stem from the fact that all locomotion, perception, and decision making must be distributed among a network of modules. This network has a dynamic topology, and each individual module has only limited resources in terms of computational power and local information about the topology in its neighborhood. To meet these challenges, this paper presents a distributed control mechanism inspired by the concept of hormones in biological systems. We view hormones as broadcast messages that trigger different actions in different modules, and exploit such to coordinate motions and perform reconfiguration in the context of limited communications and dynamic network topologies. The paper develops a primitive theory of hormone-based control, and reports the experimental results of applying such a control mechanism to our CONRO metamorphic robots, along with the results of simulations. }, address = {Venice, Italy}, author = {Wei-Min Shen and Behnam Salemi and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {Intl. Conf. on Intelligent Autonomous Systems (IAS-6)}, pages = {918--925}, publisher = {IOS Press}, title = {Hormones for Self-Reconfigurable Robots}, year = {2000} } @Article{ castano2000conro:-towards-deployable-robots, abstract = {Metamorphic robots are modular robots that can reconfigure their shape. Such capability is desirable in tasks such as earthquake search and rescue and battlefield surveillance and scouting, where robots must go through unexpected situations and obstacles and perform tasks that are difficult for fixed-shape robots. The capabilities of the robots are determined by the design specification of their modules. In this paper, we present the design specification of a CONRO module, a small, self-sufficient and relatively homogeneous module that can be connected to other modules to form complex robots. These robots have not only the capability of changing their shape (intra-robot metamorphing) but also can split into smaller robots or merge with other robots to create a single larger robot (inter-robot metamorphing), i.e., CONRO robots can alter their shape and their size. Thus, heterogeneous robot teams can be built with homogeneous components. Furthermore, the CONRO robots can separate the reconfiguration stage from the locomotion stage, allowing the selection of configuration-dependent gaits. The locomotion and automatic inter-module docking capabilities of such robots were tested using tethered prototypes that can be reconfigured manually. We conclude the paper discussing the future work needed to fully realize the construction of these robots.}, author = {Andres Castano and Wei-Min Shen and Peter Will}, bib2html_pubtype={Journal Papers}, journal = {Autonomous Robots}, month = jun, number = {3}, pages = {309--324}, title = {{CONRO}: Towards Deployable Robots with Inter-Robots Metamorphic Capabilities}, volume = {8}, year = {2000} } @InProceedings{ castano2001representing-and-discovering-the-configuration-of-conro, abstract = {A Conro reconfigurable robot is formed by joining a set of self-contained modules in a particular configuration; the actions of the robot are the result of the coordinated actions of its modules. These actions can be controlled using a master-slave approach only if the master can map the particular configuration of the robot to one that it already knows how to control. In this paper we discuss how to describe this configuration using graphs, how to discover a robot configuration and how to identify it as a particular known configuration. The methodology used is very general and can be applied easily to other modular robots. Experimental results for Conro quadrupeds and snakes are presented.}, author = {Andres Castano and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = icra-01, pages = {3503--3509}, title = {Representing and Discovering the Configuration of {CONRO} Robots}, year = {2001} } @InProceedings{ salemi2001hormone-controlled-metamorphic-robots, abstract = {Metamorphic robots with shape-changing capabilities provide a powerful and flexible approach to complex tasks in unstructured environments. However, due to their dynamic topology and decentralized configuration, metamorphic robots demand control mechanisms that go beyond those used by conventional robots. This paper builds on our previous results of hormone-based control, and develops a novel distributed control algorithm called CELL that can select, synchronize, and execute gaits and other reconfiguration actions without assuming any global configuration knowledge. This algorithm is flexible enough to deal with changes of configuration, and can resolve conflicts between locally selected actions and manage multiple active hormones for producing coherent global effects. }, author = {Behnam Salemi and Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = icra-01, pages = {4194--4199}, title = {Hormone-Controlled Metamorphic Robots}, year = {2001} } @InProceedings{ shen2001docking-in-self-reconfigurable-robots, abstract = {Docking is a crucial action for self-reconfigurable robots because it supports almost all practical advantages of such robots. In addition to the classic docking challenges found in other applications, such as reliable dock/latch mechanics, effective guiding systems, and intelligent control protocols, docking in self-reconfigurable robots is also subject to some unique constraints. These constraints include the kinematics constraints imposed on the docking modules by other modules in the configuration, communication limitations between the docking and relevant modules, and the demand for distributed control software because of the dynamics of configuration. To solve these challenging problems, this paper reports a set of solutions developed in the CONRO reconfigurable robot project. The paper presents a three-stage docking process, six different alignment protocols, distributed inverse kinematics, and other techniques such as dynamic lubrication that are essential for successful docking in CONRO-like robots. These solutions enable CONRO robots to perform autonomous and distributed reconfigurations in a laboratory environment, and they also suggest important considerations for docking in self-reconfiguration in general. }, author = {Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = iros-01, keywords = { self-reconfiguration, docking}, pages = {1049--1054}, title = {Docking in Self-Reconfigurable Robots}, year = {2001} } @Article{ shen2002special-issue-on-self-reconfigurable-modular, author = {Wei-Min Shen and Mark Yim}, bib2html_pubtype={Journal Papers}, journal = {{IEEE/ASME} Trans.\ on Mechatronics}, number = {4}, pages = {401--402}, title = {Self-Reconfigurable Modular Robots, Guest Editorial}, url = {http://ieeexplore.ieee.org/xpl/tocresult.jsp?isNumber=25977} , volume = {7}, year = {2002} } @InProceedings{ stoy2002global-locomotion-from-local, abstract = {We present a general distributed control algorithm for achieving locomotion of a self-reconfigurable robot. In this algorithm each module continuously performs a cyclic sequence of actions with a period . When a specified fraction of this period has elapsed a signal is sent to all child modules. Upon receiving this signal the child module resets its action sequence making it delayed compared to its parent. The algorithm is minimal and robust to loss of synchronization signals and change in the number of modules. We show in three different experiments that the algorithm can be used to implement a caterpillar, a sidewinder, and a rolling wheel gait in a real self-reconfigurable robot consisting of eight modules. }, author = {Kasper St{\o}y and Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {Proc. 7th Intl. Conf. on Intelligent Autonomous Systems (IAS-7)}, pages = {309--316}, title = {Global locomotion from local interaction in self-reconfigurable robots}, year = {2002} } @InProceedings{ stoy2002how-to-make-a-self-reconfigurable-robot-run, abstract = {In this paper we present role based control which is a multi-agent based control algorithm for self-reconfigurable robots. We use role based control to implement quadruped and hexapod gaits in a real self-reconfigurable robot made from up to nine independent autonomous modules. We show that this implementation scales and argue that it is minimal, robust to module failures, to loss of communication signals, and to interchange of modules. In role based control all modules of the robot run identical programs, but may play different roles. The modules decide what role to play based on their local configuration and information propagated down to them through the configuration tree. A role consists of a cyclic motion, the period of this motion, and a set of delays. The delays specify the phase delay of the cyclic motions of the child modules compared to the parent. These delays are used to coordinate the motions of the individual module to obtain a coordinated global behavior. }, address = {Bologna, Italy}, author = {Kasper St{\o}y and Wei-Min Shen and Peter Will}, bib2html_pubtype={Conference Papers}, booktitle = {Proc. First Intl. Joint Conf. on Autonomous Agents \& Multiagent Systems}, pages = {813--820}, title = {How to Make a Self-Reconfigurable Robot Run}, year = {2002} } @Article{ shen2002hormone-inspired-adaptive-communication-and-distributed, abstract = {Presents a biologically inspired approach to two basic problems in modular self-reconfigurable robots: adaptive communication in self-reconfigurable and dynamic networks, and distributed collaboration between the physically coupled modules to accomplish global effects such as locomotion and reconfiguration. Inspired by the biological concept of hormone, the paper develops the adaptive communication (AC) protocol that enables modules continuously to discover changes in their local topology, and the adaptive distributed control (ADC) protocol that allows modules to use hormone-like messages in collaborating their actions to accomplish locomotion and self-reconfiguration. These protocols are implemented and evaluated, and experiments in the CONRO self-reconfigurable robot and in a Newtonian simulation environment have shown that the protocols are robust and scaleable when configurations change dynamically and unexpectedly, and they can support online reconfiguration, module-level behavior shifting, and locomotion. The paper also discusses the implication of the hormone-inspired approach for distributed multiple robots and self-reconfigurable systems in general.}, author = {Wei-Min Shen and Behnam Salemi and Peter Will}, bib2html_pubtype={Journal Papers}, journal = tra, month = oct, number = {5}, pages = {700--712}, title = {Hormone-Inspired Adaptive Communication and Distributed Control for {CONRO} Self-Reconfigurable Robots}, volume = {18}, year = {2002} } @Article{ stoy2002using-role-based-control-to-produce, abstract = {This paper presents a role-based approach to the problem of controlling locomotion of chain-type self-reconfigurable robots. In role-based control, all modules are controlled by identical controllers. Each controller consists of several playable roles and a role-selection mechanism. A role represents the motion of a module and how it synchronizes with connected modules. A controller selects which role to play depending on the local configuration of the module and the roles being played by connected modules. We use role-based control to implement a sidewinder and a caterpillar gait in the CONRO self-reconfigurable robot. The robot is made from up to nine modules connected in a chain. We show that the locomotion speed of the caterpillar gait is constant even with loss of 75\% of the communication signals. Furthermore, we show that the speed of the caterpillar gait decreases gracefully with a decreased number of modules. We also implement a quadruped gait and show that without changing the controller the robot can be extended with an extra pair of legs and produce a hexapod gait. Based on these experiments, we conclude that role-based control is robust to signal loss, scales with an increased number of modules, and is a simple approach to the control of locomotion of chain-type self-reconfigurable robots.}, author = {Kasper St{\o}y and Wei-Min Shen and Peter Will}, bib2html_pubtype={Journal Papers}, journal = {{IEEE/ASME} Trans. on Mechatronics}, month = dec, number = {4}, pages = {410--417}, title = {Using role-based control to produce locomotion in chain-type self-reconfigurable robots}, volume = {7}, year = {2002} } @Article{ castano2002the-conro-modules-for-reconfigurable-robots, abstract = {The goal of the Conro Project is to build deployable modular robots that can reconfigure into different shapes such as snakes or hexapods. Each Conro module is, itself, a robot and hence a Conro robot is actually a multirobot system. In this paper we present an overview of the Conro modules, the design approach, an overview of the mechanical and electrical systems and a discussion on size versus power requirement of the module. Each module is self-contained; it has its own processor, power supply, communication system, sensors and actuators. The modules, although self-contained, were designed to work in groups, as part of a large modular robot. We conclude the paper by describing some of the robots that we have built using the Conro modules and describing the miniature custom-made Conro camera as an example of the type of sensors that can be carried as payload by these robots. }, author = {Andres Castano and Alberto Behar and Peter Will}, bib2html_pubtype={Journal Papers}, journal = {{IEEE/ASME} Trans.\ Mechatronics}, keywords = { self-reconfiguration}, month = dec, number = {4}, pages = {403--409}, title = {The {Conro} Modules for Reconfigurable Robots}, volume = {7}, year = {2002} } @Article{ shen2003self-organization-through-digital-hormones, author = {Wei-Min Shen}, bib2html_pubtype={Journal Papers}, journal = {{IEEE} Intelligent Systems}, number = {4}, pages = {81--83}, title = {Self-Organization through Digital Hormones}, volume = {18}, year = {2003} } @Misc{ shen2003us-patent, author = {Wei-Min Shen and Behnam Salemi and Peter Will}, bib2html_pubtype={Patents}, title = {{US} Patent \#6,635,781, {D}istributed Control and Collaboration of Autonomous Agents in a Dynamic Reconfigurable System}, year = {2003} } @InProceedings{ salemi2003distributed-task-negotiation-in-self-reconfigurable, abstract = {A self-reconfigurable robot can be viewed as a network of many autonomous modules. Driven by their local information, the modules can initiate tasks that may conflict with each other at the global level. How the modules negotiate and select a coherent task among many competing tasks is thus a critical problem for the control of self-reconfigurable robots. This paper presents a distributed algorithm called DISTINCT to solve this challenging problem and show that it can be successfully applied to the CONRO self-reconfigurable robots. A discussion how to apply DISTINCT to other types of distributed systems such as sensor network, swarm robots, or multi-agent systems is also given.}, author = {Behnam Salemi and Peter Will and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-03, pages = {2448--2453}, title = {Distributed task negotiation in self-reconfigurable robots}, year = {2003} } @Article{ salemi2003distributed-task-negotiation-in-modular, author = {Behnam Salemi and Peter Will and Wei-Min Shen}, bib2html_pubtype={Journal Papers}, journal = {Journal of the Robotics Society of Japan, Special Issue on ``Modular Robots''}, month = nov, number = {8}, pages = {32--39}, title = {Distributed Task Negotiation in Modular Robots}, volume = {21}, year = {2003} } @Article{ jiang2004integument-pattern-formation-involves, abstract = {Pattern formation is a fundamental morphogenetic process. Models based on genetic and epigenetic control have been proposed but remain controversial. Here we use feather morphogenesis for further evaluation. Adhesion molecules and/or signaling molecules were first expressed homogenously in feather tracts (restrictive mode, appear earlier) or directly in bud or inter-bud regions (de novo mode, appear later). They either activate or inhibit bud formation, but paradoxically co-localize in the bud. Using feather bud reconstitution, we showed that completely dissociated cells can reform periodic patterns without reference to previous positional codes. The patterning process has the characteristics of being self-organizing, dynamic and plastic. The final pattern is an equilibrium state reached by competition, and the number and size of buds can be altered based on cell number and activator/inhibitor ratio, respectively. We developed a Digital Hormone Model which consists of (1) competent cells without identity that move randomly in a space, (2) extracellular signaling hormones which diffuse by a reaction-diffusion mechanism and activate or inhibit cell adhesion, and (3) cells which respond with topological stochastic actions manifested as changes in cell adhesion. Based on probability, the results are cell clusters arranged in dots or stripes. Thus genetic control provides combinational molecular information which defines the properties of the cells but not the final pattern. Epigenetic control governs interactions among cells and their environment based on physical-chemical rules (such as those described in the Digital Hormone Model). Complex integument patterning is the sum of these two components of control and that is why integument patterns are usually similar but non-identical. These principles may be shared by other pattern formation processes such as barb ridge formation, fingerprints, pigmentation patterning, etc. The Digital Hormone Model can also be applied to swarming robot navigation, reaching intelligent automata and representing a self-re-configurable type of control rather than a follow-the-instruction type of control. }, author = {T.-X. Jiang and R. Wideltz and Wei-Min Shen and Peter Will and D. Wu and C. Lin and J. Jung and C. Chuong}, bib2html_pubtype={Journal Papers}, journal = {Int.\ J.\ Dev.\ Biol.}, pages = {117--135}, title = {Integument pattern formation involves genetic and epigenetic controls operated at different levels: feather arrays simulated by a Digital Hormone Model}, volume = {48}, year = {2004} } @Article{ shen2004hormone-inspired-self-organization-and-distributed-control, abstract = {The control of robot swarming in a distributed manner is a difficult problem because global behaviors must emerge as a result of many local actions. This paper uses a bio-inspired control method called the Digital Hormone Model (DHM) to control the tasking and executing of robot swarms based on local communication, signal propagation, and stochastic reactions. The DHM model is probabilistic, dynamic, fault-tolerant, computationally efficient, and can be easily tasked to change global behavior. Different from most existing distributed control and learning mechanisms, DHM considers the topological structure of the organization, supports dynamic reconfiguration and self-organization, and requires no globally unique identifiers for individual robots. The paper describes the DHM and presents the experimental results on simulating biological observations in the forming of feathers, and simulating wireless communicated swarm behavior at a large scale for attacking target, forming sensor networks, self-repairing, and avoiding pitfalls in mission execution. }, author = {Wei-Min Shen and Peter Will and Aram Galstyan and Cheng-Ming Chuong}, bib2html_pubtype={Journal Papers}, journal = {Autonomous Robots}, keywords = { self organization, self-reconfiguration, modular robots, distributed control, robot swarms, digital hormones}, month = jul, number = {1}, pages = {93--105}, title = {Hormone-Inspired Self-Organization and Distributed Control of Robotic Swarms}, volume = {17}, year = {2004} } @Article{ modi2005adopt:-asynchronous-distributed-constraint, abstract = {The Distributed Constraint Optimization Problem (DCOP) is a promising approach for modeling distributed reasoning tasks that arise in multiagent systems. Unfortunately, existing methods for DCOP are not able to provide theoretical guarantees on global solution quality while allowing agents to operate asynchronously. We show how this failure can be remedied by allowing agents to make local decisions based on conservative cost estimates rather than relying on global certainty as previous approaches have done. This novel approach results in a polynomial-space algorithm for DCOP named Adopt that is guaranteed to find the globally optimal solution while allowing agents to execute asynchronously and in parallel. Detailed experimental results show that on benchmark problems Adopt obtains speedups of several orders of magnitude over other approaches. Adopt can also perform bounded-error approximation--it has the ability to quickly find approximate solutions and, unlike heuristic search methods, still maintain a theoretical guarantee on solution quality.}, author = {P. J. Modi and Wei-Min Shen and M. Tambe and M. Yokoo}, bib2html_pubtype={Journal Papers}, journal = {Artificial Intelligence Journal}, keywords = { multiagent systems; constraints; distributed optimization}, month = jan, number = {1-2}, pages = {149--180}, title = {{ADOPT}: Asynchronous Distributed Constraint Optimization with Quality Guarantees}, volume = {161}, year = {2005} } @InProceedings{ salemi2006superbot, address = {Beijing, China}, author = {Behnam Salemi and Mark Moll and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-06, month = oct, title = {{SUPERBOT}: A Deployable, Multi-Functional, and Modular Self-Reconfigurable Robotic System}, year = {2006} } @InProceedings{ moll2006distributed-control-of-the-center-of-mass, abstract = {We present a distributed controller for the center of mass of a modular robot. This is useful for locomotion of a modular robot over uneven and unknown terrain. By controlling the center of mass, a robot can prevent itself from falling over. We present a distributed and decentralized algorithm that computes the mass properties of the robot. Additionally, each module also computes the mass properties of the modules that are directly or indirectly connected to each of its connectors. With this information, each module can independently steer the center of mass towards a desired position by adjusting its joint positions. We present simulation results that show the feasibility of the approach.}, address = {Beijing, China}, author = {Mark Moll and Peter Will and Maks Krivokon and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-06, month = oct, title = {Distributed Control of the Center of Mass of a Modular Robot}, year = {2006} } @Article{ wei-min-shen2006multimode-locomotion-for-reconfigurable-robots, abstract = {One of the most challenging issues for a self-sustaining robotic system is how to use its limited resources to accomplish a large variety of tasks. The scope of such tasks could include transportation, exploration, construction, inspection, maintenance,in-situ resource utilization, and support for astronauts. This paper proposes a modular and reconfigurable solution for this challenge by allowing a robot to support multiple modes of locomotion and select the appropriate mode for the task at hand. This solution relies on robots that are made of reconfigurable modules. Each locomotion mode consists of a set of characteristics for the environment type, speed, turning-ability, energy-efficiency, and recoverability from failures. This paper demonstrates a solution using the SuperBot robot that combines advantages from M-TRAN, CONRO, ATRON, and other chain-based and lattice-based robots. At the present, a single real SuperBot module can move, turn, sidewind, maneuver, and travel on batteries up to 500 m on carpet in an office environment. In physics-based simulation, SuperBot modules can perform multimodal locomotions such as snake, caterpillar, insect, spider, rolling track, H-walker, etc. It can move at speeds of up to 1.0 m/s on flat terrain using less than 6 W per module, and climb slopes of no less 40 degrees.}, author = {Wei-Min Shen and Maks Krivokon and Harris Chiu and Jacob Everist and Michael Rubenstein and Jagadesh Venkatesh}, bib2html_pubtype={Journal Papers}, journal = {Autonomous Robots}, keywords = { modular, multifunctional and self-reconfigurable robots, space robots, multimode gaits}, number = {2}, pages = {165--177}, title = {Multimode Locomotion for Reconfigurable Robots}, volume = {20}, year = {2006} } @Article{ RA-Magazine-2007, abstract = {The field of modular self-reconfigurable robotic systems addresses the design, fabrication, motion planning, and control of autonomous kinematic machines with variable morphology. Beyond conventional actuation, sensing, and control typically found in fixed-morphology robots, self-reconfigurable robots are also able to deliberately change their own shape by rearranging the connectivity of their parts in order to adapt to new circumstances, perform new tasks, or recover from damage. Over the last two decades, the field of modular robotics has advanced from proof-of-concept systems to elaborate physical implementations and simulations. The goal of this article is to outline some of this progress and identify key challenges and opportunities that lay ahead.}, author = {Mark Yim, Wei-Min Shen, Behnam Salemi, Daniela Rus, Mark Moll, Hod Lipson, Eric Klavins, and Gregory S. Chirikjian}, journal = {IEEE Robotics and Autonomation Magazine}, keywords = { modular and self-reconfigurable robots}, number = {}, pages = {43--53}, title = {Modular Self-Reconfigurable Robot Systems -- Challenges and Opportunities for the Future}, volume = {March}, year = {2007} } @InProceedings{ ranasinghe2007modular-robot-climbers, abstract = {The goal of modular robots is to achieve versatility in the field, while satisfying any number of traditional robot tasks. We chose the task of traversing terrain by climbing, and present various methods of climbing with modular robots. In particular, we focus on the tasks of climbing across a horizontal rope, climbing up a vertical rope, and climbing up stairs using the Superbot modular robot. The horizontal rope climber has successfully traversed a 20 meter rope at various inclines, while the vertical rope climber has successfully climbed the height of a 6 story car park on a fully charged set of batteries in under an hour.}, address = {San Diego, CA}, author = {Nadeesha Ranasinghe and Jacob Everist and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-07, month = nov, note = {IROS 2007 Workshop on Self-Reconfigurable Robots, Systems & Applications}, title = {Modular Robot Climbers}, year = {2007} } @InProceedings{ chiu2007multifunctional-superbot-with-rolling-track-configuration, abstract = {SuperBot is a modular, multifunctional and reconfigurable robotic system built for NASA applications. This paper reports the design of the 20 SuperBot modules and experimental results for multifunctional behaviors of a rolling track configuration, including a long-distance (1km) running and a steep sand dune climbing. These behaviors of a single rolling track demonstrate the multifunctional capability and endurance of the SuperBot system and also its ability to work in a rough environment condition.}, address = {San Diego, CA}, author = {Harris C. H. Chiu and Mike Rubenstein and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-07, month = nov, note = {IROS 2007 Workshop on Self-Reconfigurable Robots, Systems & Applications}, title = {Multifunctional SuperBot with Rolling Track Configuration}, year = {2007} } @InProceedings{ hou2007remotely-controlled-autonomous-tricyclebot-locomotion-via-superbot, abstract = {This paper presents a new gait called tricycleBot, which is implemented on a reconfigurable modular robot called SuperBot. In this paper, the design of SuperBot is first reviewed, and then the configuration design and locomotion control of tricycleBot is described. Two different wireless controllers are used to remotely control tricycleBot. Experiment results show that tricycleBot is capable of carrying payloads more than 5 times of its own weight with satisfactory speed. It can also be steered remotely to move forward/backward, turn left/right, and travel over 1 km on a fully charged set of batteries in a carpeted office environment, or over 2 km on a smooth marble surface.}, address = {San Diego, CA}, author = {Feili Hou and Nadeesha Ranasinghe and Behnam Salemi and Wei-Min Shen}, bib2html_pubtype={Conference Papers}, booktitle = iros-07, month = nov, note = {IROS 2007 Workshop on Self-Reconfigurable Robots, Systems & Applications}, title = {Remotely-Controlled Autonomous TricycleBot Locomotion via SuperBot}, year = {2007} }