Vision-based topological mapping and localisation

Competent navigation in an environment is a major requirement for an autonomous mobile robot to accomplish its mission. Nowadays, many successful systems for navigating a mobile robot use an internal map which represents the environment in a detailed geometric manner. However, building, maintaining and using such environment maps for navigation is difficult because of perceptual aliasing and measurement noise. Moreover, geometric maps require the processing of huge amounts of data which is computationally expensive. This thesis addresses the problem of vision-based topological mapping and localisation for mobile robot navigation. Topological maps are concise and graphical representations of environments that are scalable and amenable to symbolic manipulation. Thus, they are well-suited for basic robot navigation applications, and also provide a representational basis for the procedural and semantic information needed for higher-level robotic tasks. In order to make vision-based topological navigation suitable for inexpensive mobile robots for the mass market we propose to characterise key places of the environment based on their visual appearance through colour histograms. The approach for representing places using visual appearance is based on the fact that colour histograms change slowly as the field of vision sweeps the scene when a robot moves through an environment. Hence, a place represents a region of the environment rather than a single position. We demonstrate in experiments using an indoor data set, that a topological map in which places are characterised using visual appearance augmented with metric clues provides sufficient information to perform continuous metric localisation which is robust to the kidnapped robot problem. Many topological mapping methods build a topological map by clustering visual observations to places. However, due to perceptual aliasing observations from different places may be mapped to the same place representative in the topological map. A main contribution of this thesis is a novel approach for dealing with the perceptual aliasing problem in topological mapping. We propose to incorporate neighbourhood relations for disambiguating places which otherwise are indistinguishable. We present a constraint based stochastic local search method which integrates the approach for place disambiguation in order to induce a topological map. Experiments show that the proposed method is capable of mapping environments with a high degree of perceptual aliasing, and that a small map is found quickly. Moreover, the method of using neighbourhood information for place disambiguation is integrated into a framework for topological off-line simultaneous localisation and mapping which does not require an initial categorisation of visual observations. Experiments on an indoor data set demonstrate the suitability of our method to reliably localise the robot while building a topological map.

Yet to be known

TBA: Triptych: Digital Print, PVC Text, Acrylic Sheet Total Size: 252cm x 119cm---------- The work employs text based representations of indigenous plants (3500 species names) and quotations from an eminent botanist. This information is spatialised to represent the geographic area within which the plants where recorded (by others-Gov’t database).---------- The work was exhibited at Eyes wide open (curators K Bradby and A Brandenberg) which was held at Gorepani Gallery, Albany WA to coincide with the first national screening on SBS Television of the Western Australian documentary A Million Acres a Year (Rijavec, F, Harrison, N & Bradby K (directors), Snakewood Films & Film Australia, c2003).

Many Mount Barrens

Cibachrome photographic prints, Digital print, Acrylic Sheet , wire & card.--------- Total size: 170cm x 119cm x 15cm---------- The work employs a terrestrial photography and cartographic technique to represent a diversity of landscape types surrounding West Mt Barren in Western Australia. Sixteen views of West Mt Barren were captured over a two week period from map grid coordinates in the surround landscape. These images are configured in Many Mount Barrens in a manner which corresponds to the position from which they were recorded.---------- The work was exhibited at Eyes wide open (curators K Bradby and A Brandenberg) which was held at Gorepani Gallery, Albany WA to coincide with the first national screening on SBS Television of the Western Australian documentary A Million Acres a Year (Rijavec, F, Harrison, N & Bradby K (directors), Snakewood Films & Film Australia, c2003).

Sandplain

Triptych: Digital print, Acrylic Sheet--------- Total size: 252 cm x 119cm---------- The work employs text based representations of agricultural plants (26 species names). This information is spatialised to represent the geographic area within which the plant species are harvested.---------- The work was exhibited at Eyes wide open (curators K Bradby and A Brandenberg) which was held at Gorepani Gallery, Albany WA to coincide with the first national screening on SBS Television of the Western Australian documentary A Million Acres a Year (Rijavec, F, Harrison, N & Bradby K (directors), Snakewood Films & Film Australia, c2003).

Heathprint

The work was derived from terrestrial laser scan data of a bio-diverse landscape on the SE coast of Western Australia. The digital three dimensional scan data has been abstracted into two dimensional horizontal sections or slices. This abstraction converts the complex data into spatial information which is meaningful in the context of the act of architectural and landscape architectural design. The primary intention behind the production of the work was to expand understanding on the means of representing and then designing for sites in 'kwongan' landscapes which are constituted by highly biodiverse - and thus difficult to measure - heath vegetation. From Heathprint the author generated contour intervals of the landform upon which an associate (Daniela Simon architect) designed a work of architecture, which subsequently was awarded a commendation for residential architecture in the WA Chapter Australia Institute of Architects awards 2007.

The aesthetico-ethical subject : another narrative about being ethically responsible

This paper builds on work I presented at the PESA conference in 2007, which moved through both aesthetic and ethical theory to generate a new theory of creative integrity around the issues of autonomy, agency and authenticity. This preliminary theorizing had its origins in my undergraduate ethics classroom where I was confronted with advertising students who resisted the idea of being taught ethics, along with all the philosophical ethical theories traditionally used to do this.

Economics of non-market innovation and digital literacy

This article is an abbreviated version of a debate between two economists holding somewhat different perspectives on the nature of non-market production in the space of new digital media. While the ostensible focus here is on the role of markets in the innovation of new technologies to create new economic value, this context also serves to highlight the private and public value of digital literacy.

Narrative on the "Compliance and Regulatory Journal" : past, present and future

A conversation over a cup of coffee in late 2005 between Australasian Compliance Institute members Bill Dee and Dr Len Gainsford quickly turned to previously unsuccessful attempts to start a professional journal about compliance. There were two main issue - the difficultly in getting a professional journal off the ground and then sustaining a continuous flow of quality contributions. As practitioners, Bill and Len knew there was a considerable amount of 'thought and practice leadership' compliance material out there but they also knew that such material had not been presented in a relevant and interesting way. A foolish thought arose - could we start a professional journal that practitioners might actually read and use?

Sounds from the empty city : a practice-led case study in the confluence of music, narrative and emotion

The creative practice: the adaptation of picture book The Empty City (Megarrity/Oxlade, Hachette 2007) into an innovative, interdisciplinary performance for children which combines live performance, music, projected animation and performing objects. The researcher, in the combined roles of writer/composer proposes deliberate experiments in music, narrative and emotion in the various drafts of the adaptation, and tests them in process and performance product. A particular method of composing music for live performance is tested in against the emergent needs of a collaborative, intermedial process. The unpredictable site of research means that this project is both looking to address both pre-determined and emerging points of inquiry. This analysis (directed by audience reception) finds that critical incidents of intermediality between music, narrative, action and emotion translate directly into highlights of the performance.

2006 International digital art awards : Beijing film academy galleries, China

The field was the curation of new media within large-scale exhibition practice for Chinese audiences. The context was improved understandings of the intertwining cultures and concerns of Chinese and Western contemporary practitioners. The research uncovered a range of connective and dialogical concerns around cultural displacement and re-identification, germane to the chosen group of media artists. The methodology was principally practice-led. The research brought together 31 practitioners from Asian, European and Australasian cultures within a major highly visible Chinese exhibition context. By identifying and promoting a distinct commonality within difference amongst the diverse practitioners the exhibition successfully activated a global dialogue that incorporated environmental and cultural identity agendas within a major Chinese educational and public context - thereby promulgating cross-cultural understanding, despite the often oppressive shadowing of domestic political processes. The project was developed under the international aegis of IDA Projects (established since 1999) and was substantially supported by the Fine Art Department of the Beijing Film Academy, QUT Precincts and Platform China Art Institute. It built upon IDA’s 2005 inaugural new media exhibition at the ‘Today Art’ Museum in Beijing – now recognised as one of the leading art spaces in China. Numerous peer-reviewed grants won included the Australian Embassy in China and the Australia China Council. Through subsequent invitations from external curators the work then traveled in a range of reconfigured formats to other major venues including the Block Gallery at QUT, Brisbane and ZAIM Artspace, Yokohama Japan. A major catalogue with authoritative essays was also printed.

Copyright, digital media literacies and preservice teacher education

This article considers copyright knowledge and skills as a new literacy that can be developed through the application of digital media literacy pedagogies. Digital media literacy is emerging from more established forms of media literacy that have existed in schools for several decades and have continued to change as the social and cultural practices around media technologies have changed. Changing requirements of copyright law present specific new challenges for media literacy education because the digitisation of media materials provides individuals with opportunities to appropriate and circulate culture in ways that were previously impossible. This article discusses a project in which a group of preservice media literacy educators were introduced to knowledge and skills required for the productive and informed use of different copyrights frameworks. The students’ written reflections and video production responses to a series of workshops about copyright are discussed, as are the opportunities and challenges provided by copyright education in preservice teacher education.

Value-mapping inputs

This research aims to increase understanding of and delivery to qualitative (or intangible) outcomes and impacts of major economic infrastructure projects (i.e. bridges, roads, water infrastructure and the like), and the role of stakeholder engagement in this process.-------- Recent doctoral research completed at the Queensland University of Technology by the author investigated how the principles of corporate responsibility are applied in the construction sector. This related specifically to major economic infrastructure projects (hereafter referred to as major projects), with particular regard to urban transportation projects. One outcome of this past research was a value-mapping framework which enables organisations to track project outcomes to pre-existing corporate objectives, and report on these throughout the project life-cycle. Two recommendations for future research from that work formed the basis for this current research: • How can qualitative measurables be better integrated into decision-making on major economic infrastructure projects? • How can non-contractual stakeholders be more effectively engaged with on these projects? The link between these two areas may relate to the stakeholders’ role in qualitative indicator identification and measurement. This is a key point for future investigation.---------- The aim of this research is thus to further investigate these two areas, with the intent of (i) better defining the research direction; (ii) identifying potential research partners; and (iii) identify possible sources of future funding.

Mapping a suburb with a single camera using a biologically inspired SLAM system

This paper describes a biologically inspired approach to vision-only simultaneous localization and mapping (SLAM) on ground-based platforms. The core SLAM system, dubbed RatSLAM, is based on computational models of the rodent hippocampus, and is coupled with a lightweight vision system that provides odometry and appearance information. RatSLAM builds a map in an online manner, driving loop closure and relocalization through sequences of familiar visual scenes. Visual ambiguity is managed by maintaining multiple competing vehicle pose estimates, while cumulative errors in odometry are corrected after loop closure by a map correction algorithm. We demonstrate the mapping performance of the system on a 66 km car journey through a complex suburban road network. Using only a web camera operating at 10 Hz, RatSLAM generates a coherent map of the entire environment at real-time speed, correctly closing more than 51 loops of up to 5 km in length.

Persistent navigation and mapping using a biologically inspired SLAM system

The challenge of persistent navigation and mapping is to develop an autonomous robot system that can simultaneously localize, map and navigate over the lifetime of the robot with little or no human intervention. Most solutions to the simultaneous localization and mapping (SLAM) problem aim to produce highly accurate maps of areas that are assumed to be static. In contrast, solutions for persistent navigation and mapping must produce reliable goal-directed navigation outcomes in an environment that is assumed to be in constant flux. We investigate the persistent navigation and mapping problem in the context of an autonomous robot that performs mock deliveries in a working office environment over a two-week period. The solution was based on the biologically inspired visual SLAM system, RatSLAM. RatSLAM performed SLAM continuously while interacting with global and local navigation systems, and a task selection module that selected between exploration, delivery, and recharging modes. The robot performed 1,143 delivery tasks to 11 different locations with only one delivery failure (from which it recovered), traveled a total distance of more than 40 km over 37 hours of active operation, and recharged autonomously a total of 23 times.