Author name cluster

Kimon Roufas

Possible papers associated with this exact author name in Arrow. This page groups case-insensitive exact name matches and is not a full identity disambiguation profile.

4 papers

1 author row

IROS Conference 2003 Conference Paper

Motion planning with narrow C-space passages

Craig Eldershaw
Mark Yim
Ying Zhang
Kimon Roufas
Dave Duff

A common point of weakness in many path/motion planners is dealing with configuration spaces (C-spaces) that involve narrow gaps of passages. This is caused by the indirect representation of the C-space inherent in those planners. Unfortunately many real environments and tasks give rise to such situations. While a small number of planners do exist which reliably work in these environments, they in turn have problems when the robot has many controllable degrees of freedom. High degree of freedom motion in confined spaces is a typical problem encountered by PARC's PolyBot platform. The algorithm put forward in this paper is designed to work directly with the C-space obstacles' geometry, and so is not hampered by narrow passages. The planner is a homotopic one which solves general problems in n-dimensional C-space. The algorithm's theoretical characteristics are shown to compare very favourably with other contending planners in these specialised domains. Results of some preliminary testing are given.

Details

IROS Conference 2003 Conference Paper

Phase automata: a programming model of locomotion gaits for scalable chain-type modular robots

Ying Zhang
Mark Yim
Craig Eldershaw
Dave Duff
Kimon Roufas

Modular reconfigurable robots have the potential for great versatility and robustness; however, programming locomotion gaits for hundreds of modules remains a challenge. In this paper we present a formal model for programming locomotion gaits in chain-type modular robots: phase automata. A phase automation is an event-driven state automation with an initial phase delay. The phase delay is normally a real value between 0 and 1. Phase automata are compact representation of locomotion gaits and capable of being embedded and distributed across modules. The concepts of phase automata have been implemented on both PCs and embedded micro-processors. An XML script language and programming interface for phase automata are being built. Locomotion gaits programmed using phase automata have been tested both in simulation with 100+ modules and in hardware with 50+ modules.

Details

IROS Conference 2001 Conference Paper

Software architecture for modular self-reconfigurable robots

Ying Zhang
Kimon Roufas
Mark Yim

Modular, self-reconfigurable robots show the promise of great versatility, robustness and low cost. However, programming such robots for specific tasks, with hundreds of modules and each of which with multiple actuators and sensors, can be tedious and error-prone. The extreme versatility of the modular systems requires a new paradigm in programming. We present a software architecture for this type of robot, in particular the PolyBot, which has been developed through its third generation. The architecture, based on the properties of the PolyBot electro-mechanical design, features a multi-master/multi-slave structure in a multi-threaded environment, with three layers of communication protocols. The architecture is currently being implemented for Motorola PowerPC using vxWorks.

Details

ICRA Conference 2000 Conference Paper

PolyBot: A Modular Reconfigurable Robot

Mark Yim
Dave Duff
Kimon Roufas

Modular, self-reconfigurable robots show the promise of great versatility, robustness and low cost. The paper presents examples and issues in realizing those promises. PolyBot is a modular, self-reconfigurable system that is being used to explore the hardware reality of a robot with a large number of interchangeable modules. PolyBot has demonstrated the versatility promise, by implementing locomotion over a variety of terrain and manipulation versatility with a variety of objects. PolyBot is the first robot to demonstrate sequentially two topologically distinct locomotion modes by self-reconfiguration. PolyBot has raised issues regarding software scalability and hardware dependency and as the design evolves the issues of low cost and robustness will be resolved while exploring the potential of modular, self-reconfigurable robots.

Details