Validation of a 4DOF manoeuvring model of a high-speed vehicle-passenger trimaran

This paper presents the validation of a manoeuvring model for a novel 127m-vehicle-passenger trimaran via full scale trials. The adopted structure of the model is based on a model previously proposed in the literature with some simplifications. The structure of the model is discussed. Then initial parameter estimates are computed, and the final set of parameters are obtained via adjustments based on engineering judgement and application of a genetic algorithm so as to match the data of the trials. The validity of the model is also assessed with data from a trial different from the one use for the parameter adjustment. The model shows good agreement with the trial data.

Proposed vehicle impact speed: Severe injury probability relationships for selected crash types

Speed is recognised as a key contributor to crash likelihood and severity, and to road safety performance in general. Its fundamental role has been recognised by making Safe Speeds one of the four pillars of the Safe System. In this context, impact speeds above which humans are likely to sustain fatal injuries have been accepted as a reference in many Safe System infrastructure policy and planning discussions. To date, there have been no proposed relationships for impact speeds above which humans are likely to sustain fatal or serious (severe) injury, a more relevant Safe System measure. A research project on Safe System intersection design required a critical review of published literature on the relationship between impact speed and probability of injury. This has led to a number of questions being raised about the origins, accuracy and appropriateness of the currently accepted impact speed–fatality probability relationships (Wramborg 2005) in many policy documents. The literature review identified alternative, more recent and more precise relationships derived from the US crash reconstruction databases (NASS/CDS). The paper proposes for discussion a set of alternative relationships between vehicle impact speed and probability of MAIS3+ (fatal and serious) injury for selected common crash types. Proposed Safe System critical impact speed values are also proposed for use in road infrastructure assessment. The paper presents the methodology and assumptions used in developing these relationships. It identifies further research needed to confirm and refine these relationships. Such relationships would form valuable inputs into future road safety policies in Australia and New Zealand.

Influences on novice drivers' speed selection - a systematic review: Application and limitations of theory and methodology

Background Excessive speed is a primary contributing factor to young novice road trauma, including intentional and unintentional speeds above posted limits or too fast for conditions. The objective of this research was to conduct a systematic review of recent investigations into novice drivers’ speed selection, with particular attention to applications and limitations of theory and methodology. Method Systematic searches of peer-reviewed and grey literature were conducted during September 2014. Abstract reviews identified 71 references potentially meeting selection criteria of investigations since the year 2000 into factors that influence (directly or indirectly) actual speed (i.e., behaviour or performance) of young (age <25 years) and/or novice (recently-licensed) drivers. Results Full paper reviews resulted in 30 final references: 15 focused on intentional speeding and 15 on broader speed selection investigations. Both sets identified a range of individual (e.g., beliefs, personality) and social (e.g., peer, adult) influences, were predominantly theory-driven and applied cross-sectional designs. Intentional speed investigations largely utilised self-reports while other investigations more often included actual driving (simulated or ‘real world’). The latter also identified cognitive workload and external environment influences, as well as targeted interventions. Discussion and implications Applications of theory have shifted the novice speed-related literature beyond a simplistic focus on intentional speeding as human error. The potential to develop a ‘grand theory’ of intentional speeding emerged and to fill gaps to understand broader speed selection influences. This includes need for future investigations of vehicle-related and physical environment-related influences and methodologies that move beyond cross-sectional designs and rely less on self-reports.

Analysis and prevention of extreme vibration in high speed craft - A research framework

Extreme vibration has been reported for small, high speed craft in the maritime sector, with performance and health threatening effects on boat operators and crew. Musculoskeletal injuries are an enduring problem for high speed craft passengers. Spinal or joint injuries and neurological disorders may occur from repetitive pounding over rough water, continued vibration and single impact events. The risk from whole body vibration (WBV) induced through the small vessels mainly depends on time spent on the craft, which can’t be changed in a military scenario; as well as the number of shocks and jolts, and their magnitude and frequency. In the European Union for example, physical agents directives require all employers to control exposure to a number of physical agents including noise and vibration. The EC Vibration Directive 2002/44/EC then sets out regulations for the control of health and safety risks from the exposure of workers to hand arm vibration (HAV) and WBV in the workplace. Australia has exposure standards relating to WBV, AS 2670.1-2001 – Evaluation of human exposure to whole body vibration. This standard is identical to the ISO 2631-1:1997, Mechanical vibration and shock – Evaluation of human exposure to whole-body vibration. Currently, none of the jurisdictions in Australia have specific regulations for vibration exposures in workplaces. However vibration is mentioned to varying degrees in their general regulations, codes of practice and guidance material. WBV on high speed craft is normally caused by “continuous 'hammering' from short steep seas or wind against tide conditions. Shock on High Speed Craft is usually caused by random impacts. Military organisations need the knowledge to make informed decisions regarding their marine operations, compliance with legislation and potentially harmful health effects, and develop and implement appropriate counter-measures. Marine case studies in the UK such as published MAIB (Marine Accident Investigation Branch) reports show injuries that have occurred in operation, and subsequent MCA (Maritime Coastguard Agency) guidance is provided (MGN 436 (M+F), WHOLE-BODY VIBRATION: Guidance on Mitigating Against the Effects of Shocks and Impacts on Small Vessels. MCA, 2011). This paper proposes a research framework to study the origin, impact and pathways for prevention of WBV in small, high speed craft in a maritime environment.

Does gait speed indicate prosthetic walking potential following lower limb amputation?

Background: Gait speed is an indicator of walking ability, morbidity and mortality; and is a reliable, valid and sensitive outcome measure commonly used in the rehabilitation setting. Gait speed is a quick and efficient assessment method; yet, to date, there has been little investigation of its potential use in populations with lower limb amputation.

Speed the plough

Dancing was an important pastime in colonial society. People would dance to celebrate events such as weddings and harvests, but also as a general recreational activity. Dancing is a shared experience which forges and maintains a sense of community and cultural identity – a sense of belonging. This was significant in the new land, where many people had left their families and friends behind. Speed the Plough was a very popular English country dance which came from a play of the same name, first performed in London in 1798.

The influence of the elements of procedural justice and speed camera enforcement on young novice driver self-reported speeding

Road policing is an important tool used to modify road user behaviour. While other theories, such as deterrence theory, are significant in road policing, there may be a role for using procedural justice as a framework to improve outcomes in common police citizen interactions such as traffic law enforcement. This study, using a sample of 237 young novice drivers, considered how the four elements of procedural justice (voice, neutrality, respect and trustworthiness) were perceived in relation to two forms of speed enforcement: point-to-point (or average) speed and mobile speed cameras. Only neutrality was related to both speed camera types suggesting that it may be possible to influence behaviour by emphasising one or more elements, rather than using all components of procedural justice. This study is important as it indicates that including at least some elements of procedural justice in more automated policing encounters can encourage citizen compliance.

Comparison of the sensitivity of different sensor technologies to imbalance severity in low speed wind turbines

Imbalance is not only a direct major cause of downtime in wind turbines, but also accelerates the degradation of neighbouring and downstream components (e.g. main bearing, generator). Along with detection, the imbalance quantification is also essential as some residual imbalance always exist even in a healthy turbine. Three different commonly used sensor technologies (vibration, acoustic emission and electrical measurements) are investigated in this work to verify their sensitivity to different imbalance grades. This study is based on data obtained by experimental tests performed on a small scale wind turbine drive train test-rig for different shaft speeds and imbalance levels. According to the analysis results, electrical measurements seem to be the most suitable for tracking the development of imbalance.