David Yuen's Homepage
Research Interest Contact .


Introduction

I was a PhD student in the Robotics Group, which is part of the Computer System Research Cluster in the Department of Electrical and Computer Engineering. The research was supervised by Dr Bruce MacDonald and related to vision-based robot localisation. Robotic research still lacks behind the human imagination nad expectation in many fronts. It was one of the motivations that drives me to start my research in this field. My earlier research experience was more process engineering oriented. My master thesis was about the application model-predictive control for the fermentation process in a beer brewery. It would be nice to see whether my previous exposure can give me some interesting insights to a fairly different application domain.

Now I am a research fellow in the Intelligence, Agents, Multimedia (IAM) group of University of Southampton. My research focus shifts from single robot to multiple agents by applying primarily market based control methods. Please visit my new homepage at http://www.ecs.soton.ac.uk/~dy.

Research

Vision-based localisation is a biologically-inspired process.  In contrast to the development of robotic research in the past few decades, only a few types of nocturnal animals, such as bats, use direct range sensing as a mean to explore the environment.  The heavy computation requirement involved in near real-time image processing hindered the widespread use of vision in robotics.  Due to the continuous advances in electronics, this physical barrier has largely been overcome nowadays.  It is now about time for us to explore further into this fascinating area.

To be more specific, statistical vision-based localisation is my research focus.  If we want the robot to localise using natural landmarks extracted from the scene, it will have to match these landmarks before carrying out triangulation.  Image features are not unique in many scenes, which may be leaves on a tree or identical chairs in a conference room.   It is different to match these similar objects precisely.  Robust estimation methods, e.g. RANSAC, can be improved to take advantage of the extra available information.  Panoramic image geometry has a number of desirable properties, including very large field-of-view and ease processing, which is particularly relevant for robotics.  Its use has been integrated to my robot localisation algorithm.

Recent development in Sequential Monte Carlo (SMC) methods offers very efficient estimation to the Bayes' Theorem.   Many different classes of localisation problems, including absolute position estimation, tracking and the very difficult kidnapped robot problem, have been solved using SMC.  Possible extension to localisation problems, in which neither robot nor landmark positions are known, is one of the other direction that I am researching on at this moment.  Research to extend the algorithm for localisation using image features is still on-going.

For more details:

Panoramic iamge with epipolar lines
Panoramic image with cylindrical projection. (epipolar lines are shown in green)
SMC based localisation
SMC robot localisation simulation.  The blue spots are individual "particles" whereas the current robot positiin is represented in green.

Technical Interests

In this section, I am going to put a few scripts/programs/designs that I have worked on previously. Some are originated from my research, some are just my personal interest.

Other Interests


Contact Info

Postal Address:
Department of Electrical and Computer Engineering
School of Engineering, University of Auckland
Private Bag 92019, Auckland, New Zealand.
Physical Address:
Room 2.308 (a.k.a. SPACE Lab),
Level 3, 20 Symonds Street
URL:
www.ece.auckland.ac.nz/~cyue001
Email:
d.yuen@auckland.ac.nz
Phone:
+64-9-3737599 ext 88104



Last Updated:   Web Jul 6 10:59:52 NZDT 2005