Author name cluster

Dave Duff

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.

5 papers

1 author row

ICRA Conference 2004 Conference Paper

PolyBot and PolyKinetic™ System: a Modular Robotic Platform for Education

Alex Golovinsky
Mark Yim
Ying Zhang
Craig Eldershaw
Dave Duff

Modular robotics has been an active area of research for the last decade. In this paper, we argue that it also provides an excellent platform for education. PolyBot is a type of modular reconfigurable robot developed at PARC. The PolyKinetic/spl trade/ System provides a robotic scripting language and programming environment for controlling this type of robot. Based on experience with mentoring high school students, and running a tutorial for robotic researchers at IROS'03, we show that, PolyBot and the PolyKinetic/spl trade/ System is effective for educational activities at multiple levels. These include playing, exploring, building, programming, competing, and most of all, learning while having fun.

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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.

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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.

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IROS Conference 2001 Conference Paper

Closed-chain motion with large mechanical advantage

Mark Yim
Dave Duff
Ying Zhang

One of the constraints that severely limit the capability of highly redundant manipulator arms is the actuator torque limits. This paper presents a way to achieve large effective forces from weak actuators by exploiting the large mechanical advantage that results from systems near singularities. While large mechanical advantages have been applied near singularities in many instances, this method allows the application of this large force over a large distance. It is applied specifically to closed chain mechanisms and demonstrated on the PolyBot modular self-reconfigurable robot.

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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.

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