A nonlinear PI and backstepping based controller for tractor-steerable trailer influenced by slip

Autonomous guidance of agricultural vehiclesis vital as mechanized farming production becomes more prevalent. It is crucial that tractor-trailers are guided with accuracy in both lateral and longitudinal directions, whilst being affected by large disturbance forces, or slips, owing to uncertain and undulating terrain. Successful research has been concentrated on trajectory control which can provide longitudinal and lateral accuracy if the vehicle moves without sliding, and the trailer is passive. In this paper, the problem of robust trajectory tracking along straight and circular paths of a tractor-steerable trailer is addressed. By utilizing a robust combination of backstepping and nonlinear PI control, a robust, nonlinear controller is proposed. For vehicles subjected to sliding, the proposed controller makes the lateral deviations and the orientation errors of the tractor and trailer converge to a neighborhood near the origin. Simulation results are presented to illustrate that the suggested controller ensures precise trajectory tracking in the presence of slip.

Corporate, risk, mining camps and knowledge/power

Australia is currently in the midst of a major resources boom. However the benefits from the boom are unevenly distributed, with state governments collecting billions in royalties, and mining companies billions in profits. The costs are borne mostly at a local level by regional communities on the frontier of the mining boom, surrounded by thousands of men housed in work camps. The escalating reliance on non–resident workers housed in camps carries significant risks for individual workers, host communities and the provision of human services and infrastructure. These include rising rates of fatigue–related death and injuries, rising levels of alcohol–fuelled violence, illegally erected and unregulated work camps, soaring housing costs and other costs of living, and stretched basic infrastructure undermining the sustainability of these towns. But these costs have generally escaped industry, government and academic scrutiny. This chapter directs a critical gaze at the hopelessly compromised industry–funded research vital to legitimating the resource sector’s self–serving knowledge claims that it is committed to social sustainability and corporate responsibility. The chapter divides into two parts. The first argues that post–industrial mining regimes mask and privatise these harms and risks, shifting them on to workers, families and communities. The second part links the privatisation of these risks with the political economy of privatised knowledge embedded in the approvals process for major resource sector projects.

Creativity is as important as literacy : making a film trailer responding to literature

The first part of the title is from Sir Ken Robinson (Robinson, 2009), the esteemed educator and champion of creativity in schools. Sometimes in the face of meeting the demands of time, timetabling, demanding administration tasks and teaching for high stakes testing accountability, we can find ourselves desperate for time to remember that English has always been one of the places in schools where creativity can flourish. English is a place for the play of the imagination. English teachers are the purveyors of narrative; the keepers and teachers of stories. The new Australian Curriculum: English, (Australian Curriculum and Assessment Reporting Authority (ACARA), 2012) asks us to be using ICT technologies in creative ways to tell those stories. The curriculum asks students to access texts receptively and to then speak about, write and create texts productively. There are so many interesting things to do with texts beyond word processing of print based resources. Responding to literature through media is always an alternative option to writing or simply speaking about it. In this paper my QUT pre-service student Chrystal Armitage describes how she made a mini story via a film trailer in response to a short story, ‘Turned’ (Gilman, 1987) in the unit, Literature in Secondary Teaching.

Dynamic load-sharing of longitudinal-connected air suspensions of a tri-axle semi-trailer

The effects of suspension parameters and driving conditions on dynamic load-sharing of longitudinal-connected air suspensions of a tri-axle semi-trailer are investigated in this study. A novel nonlinear model of a multi-axle semi-trailer with longitudinal-connected air suspensions is formulated based on fluid mechanics and thermodynamics and validated through test results. The effects of road surface conditions, driving speeds, air line inside diameter and connector inside diameter on dynamic load-sharing capability of the semi-trailer were analyzed in terms of load-sharing criteria. Simulation results indicate that, when larger air lines and connectors are employed, the DLSC (Dynamic Load-Sharing Coefficient) optimization ratio reaches its peak value when the road roughness is medium. The optimization ratio fluctuates in a complex manner as driving speed increases. The results also indicate that if the air line inside diameter is always assumed to be larger than the connector inside diameter, the influence of air line inside diameter on load-sharing is more significant than that of the connector inside diameter. The proposed approach can be used for further study of the influence of additional factors (such as vehicle load, static absolute air pressure and static height of air spring) on load-sharing and the control methods for multi-axle air suspensions with longitudinal air line.

Scared straight : boot camps for Queensland

The Liberal National Party (‘LNP’) ‘tough on youth crime’ policy mantra was well publicised in the months leading up to the 2012 Queensland state election. 1 Boot camp trials were espoused as a quick-fix panacea — a way of addressing youth offending. The idea was particularly favoured in the far northern regions of the state. In line with the new government’s policy, the Youth Justice (Boot Camp Orders) and Other Legislation Amendment Bill 2012 (Qld) (‘the Bill’) had a speedy passage through the unicameral Queensland parliament. It was introduced on 1 November 2012, scrutinised by the Legal Affairs and Community Safety Committee (‘LACSC’) which sought community feedback, and reported back to Parliament within the given timeframe of three weeks. The Bill received assent early December and the provisions commenced in January 2013. This article examines the legislative changes implemented in Queensland. It analyses the issues prompting the amendments such as the perception that parts of Queensland were in the grip of a ‘soaring juvenile crime rate’, the conservative government’s ‘tough stance’ policy towards youth offending, and the transfer of youth justice ‘solutions’ such as ‘boot camps’ among jurisdictions. The article assesses the evidence base for boot camp orders as an option in sentencing young offenders and concludes by raising serious concerns about pursuing such a narrow hardline approach to youth justice.

Hard Lessons : Reflections on Governance and Crime Control in Late Modernity

The essays in this book catalogue a wide and varied range of instances where 'things go wrong' in the practice of criminal justice. The contributions document instances where laws, policies and practices have produced unintended consequences of the most deleterious kind, drawing attention to 'boot camps', detention centres and specific penal policies such as 'short, sharp shock' and 'three strikes and you're out'. Also examined are policing practices such as 'zero tolerance', 'saturation policing' and punitive laws in the area of drug use, sex offences, and prostitution. It will be demonstrated that in each of these cases, the objectives of government resulted in the creation of new and unforeseen problems requiring further reform to the justice system.

Globalization, frontier masculinities and violence : booze, blokes and brawls

Over the last two decades, two new trajectories have taken hold in criminology - the study of masculinity and crime, after a century of neglect, and the geography of crime. This article brings both those fields together to analyse the impact of globalisation in the resources sector on frontier cultures of violence. This paper approaches this issue through a case study of frontier masculinities and violence in communities at the forefront of generating resource extraction for global economies. This paper argues that the high rates of violence among men living in work camps in these socio-spatial contexts cannot simply be understood as individualised expressions of psycho-pathological deficit or social disorganisation. Explanations for these patterns of violence must also consider a number of key subterranean convergences between globalising processes and the social dynamics of male-on-male violence in such settings.

Towards a culturally appropriate mental health system: Sudanese-Australians' experiences with trauma

Australia is fortunate to welcome approximately 13,000 humanitarian entrants per year, most of whom have experienced protracted violence, hardship and life in refugee camps. The majority of humanitarian migrants were raised in cultural contexts very different to that of Australia, contributing to the increasing diversity of this region. With this diversity comes a responsibility to ensure every Australian receives culturally appropriate mental healthcare. Those who are forced into migration have experienced trauma and the stress of acculturation often compounds this trauma. This study investigated the experience of trauma from the perspectives of Sudanese-Australians. Grounded theory methodology was employed to extract themes from interviews with 15 Sudanese-Australians aged between 19 and 49 years. Results demonstrated four overarching themes: support, religion, strength and new possibilities. The data within these themes are compared and contrasted with previous literature that has examined notions of trauma, distress and growth in western populations. Conclusions drawn from these results highlight the need to build inclusive practices that support diversity into existing trauma services in Australia.

Novel car carrier design : prevention of falls from heights

This article reports the details of a research on novel design in the field of semitrailer sector and discuss design by hazard prevention techniques. The novel design made addresses occupational health and safety (OHS)concerns of fall from heights. The research includes a detailed survey of national data sources to examine the fatalities caused due to fall from heights in car carriers. The study investigates OHS recommendations in Australia for semitrailer sector. Often injuries are caused due to drivers working above the 1.5 meter height for loading, unloading of the cars, moving the decks up, down, strapping the cars, and slipperly. The new design is developed using latest computer aided design and engineeing (CAD, CAE), product data management (PDM), virtual design process (VDP). The new car carrier design excels in reducing the risks of injuries to drivers and new bench mark for OHS standards. The new design has all the decks operated with hydraulics and uses unique ratchet lock mechanism (fool proof design) and loading happens at a safe working height (below 1.5 meter). All the cars are strapped on the safe working height, and then car desks operated hydraulically to transfer them to the required position. This also includes the car on the prime mover, which shuttles across from one deck to other using hydraulic and rack-pinion mechanisms. The novel design car carrier solves the problem of falls from height: next step would be to transfer this technology across other similar effected sectors.

Nurturing Needs: Literacy Achievement for Refugee students

Yeronga State School, located 7 km from the city in Brisbane, Queensland, opened in 1871. YSS caters for a middle class inner-suburban community, however, from the mid 1990s enrolments brought new forms of socio-economic, cultural and linguistic diversity. Initially, ESL students were enrolled due to their immigrant parents enrolling in the neighbouring TAFE. Then refugee families from Bosnia and the Middle East became part of the YSS community. In recent years, refugee numbers have accounted for up to 23% of the school population. Many of these new arrivals left behind families in war-torn circumstances, were orphaned or came to live with unknown relatives. Some family members were victims of torture which may have been witnessed by the children. Trauma for some or all family members was a very real concern. Others were born in refugee camps, where food was scarce, belongings needed to be guarded and safety was never guaranteed.

The resource boom's underbelly : criminological impacts of mining development

Australia is currently in the midst of a major resources boom. Resultant growing demands for labour in regional and remote areas have accelerated the recruitment of non resident workers, mostly contractors, who work extended block rosters of 12-hour shifts and are accommodated in work camps, often adjacent to established mining towns. Serious social impacts of these practices, including violence and crime, have generally escaped industry, government and academic scrutiny. This paper highlights some of these impacts on affected regional communities and workers and argues that post-industrial mining regimes serve to mask and privatize these harms and risks, shifting them on to workers, families and communities.

Violent urbanism is us

This paper explores violent urbanism in the recent science-fiction filem District 9 whhich depicts an alien immigration camp, filmed on location in Soweto in 2008 in the midst of a series of violent clashed between indigenous South Africans and the new wave of African immigrants. Violent Urbanism is the State of method of control of bodies and populations by those precise biological techniques that determine geopolitical sites for the control of cities. This film while presented as cinema verite speaks the real invasion of traditional, spatio-disciplinary regimes such as corporate-run detention centres, refugee camps, border control and enforced relocation by those imperceptible techniques which violate the body by reducing it to a biological datum, tool, or specimen to serve the security agenda of the twenty-first century nation-state. These techniques are chemical and biological warfare proliferation; genetic engineering; and surveillance systems, such as biometrics, whose purview is no longer limited to the specular but includes the molecular. District 9 evinces a compelling urban image of contemporary biopolitics that disturbs the received historiography of post-apartheid urbanism. Clearly Johannesburg is not the only place this could or is happening - the reach of biopolitics is worldwide. District 9 visualises with utter precision the corporate hijacking of the biological realm in contemporary cites, just as it asks the unsettling question, who exactly is the "audience" of Violent Urbanism?