Lehiaketako motozikleta baten txasisaren diseinu estrukturala

[EU]Lan honetan lehiaketako motozikleta baten txasisaren diseinu estrukturala egiten da. Zehazki esanda txasisaren aurreko aldea edo motorra inguratzen duena, sub-txasisa eta baskulatzailearekin bat egiten duen txapa kontuan hartu gabe. Lehenik sarreratxo bat egiten da txasisaren ezaugarri ezberdinak, mota ezberdinak azalduz eta zeintzuk diren lortu beharreko helburuak adieraziz. Hauek lortzeak ekarriko dituen onura zientifiko teknikoak zein ekonomikoak zeintzuk diren ere deskribatuko dira. Ondoren lana burutzeko ze metodologia jarraitu den agertzen da hasieratik bukaerara eman beharreko pausuak zeintzuk diren esanez. Gero metodologia hau aplikatuz egin diren diseinu ezberdinak jarriko dira bakoitza bere emaitzekin. Bukatzeko emaitza hauek konparatu eta konklusio batzuk aterako dira zein den diseinu egokiena jakiteko.

Diseño estructural de un basculante de moto de competición

[ES]En este trabajo se plantea una propuesta de diseño estructural de un basculante de una moto de competición de 250cc y 4T adecuado a las normas de la competición MotoStudent entre universidades. En primer lugar se estudian los distintos tipos de basculante existentes y se ponderan sus ventajas e inconvenientes. Posteriormente se elige uno de los tipos en base a las características de la moto y se desarrolla. La herramienta utilizada para el desarrollo es el programa PTC Creo 2.0. Primero se realiza el diseño en CAD de la pieza y después se estudia el diseño con el método de elementos finitos y se modifica hasta alcanzar los requisitos necesarios. Finalmente se añaden elementos auxiliares necesarios y se realizan los planos de la pieza.

Suspensión trasera regulable pra una moto de competición: altenrativa full-floater

[ES] El objeto de este estudio consiste en el diseño de un sistema de suspensión trasera regulable y progresiva, así como el prediseño de un basculante, para una motocicleta de competición. La motocicleta compite dentro de la categoría MotoStudent, por lo que se ha realizado el estudio de acuerdo con las normas de la Organización y las especificaciones del equipo de la ETSI.

Diseño de tijas y acople de pinza de freno para moto de competición.

[ES]Este trabajo pretende realizar el diseño de las tijas y del acople de freno para una moto de competición. El objetivo principal es conseguir un diseño óptimo de las tijas y del acople del freno. Para ello se realiza una investigación previa, se estudian las solicitaciones a las que se ven sometidas las piezas y se diseñan con un programa de CAD/MEF (PTC Creo 2.0) con su respectivo análisis de resultados. Con todo esto se pretende la posibilidad de aportar un diseño novedoso y eficaz de las tres piezas para el proyecto MotoStudent o para cualquier otro proyecto.

Diseño y fabricación de un conjunto de estriberas y semimanillares para moto de competición.

[ES]El objeto del presente trabajo consiste en diseñar un conjunto de estriberas y semimanillares para una moto de competición, que cumplan con una serie de requerimientos geométricos y que garanticen las mejores prestaciones posibles en cuanto a competición, entre las que destacan la seguridad y comodidad del piloto. A continuación se procederá a elegir los procesos más adecuados para la fabricación de los mismos, teniendo en cuenta requisitos económicos y de calidad, para sacar al mercado un producto lo más competitivo posible. El estudio se basa principalmente en el análisis de diferentes alternativas que se pueden adoptar para obtener el diseño de los productos y posterior fabricación. Para ello se estudiarán los objetivos y condiciones que se deben cumplir. Cabe destacar que la idea de desarrollo de este proyecto surgió dentro de otro de mayor envergadura, la competición MotoStudent. MotoStudent es una competición internacional entre universidades de todo el mundo en la que los equipos de estudiantes se enfrentan al desafío de diseñar y desarrollar un prototipo de motocicleta de competición similar a la categoría mundialista de Moto3.

Diseño del sistema de tensor de cadena y acople de pinza de freno trasero para moto de competición.

[ES]En este documento se propone el diseño de dos sistemas imprescindibles en el tren trasero de una moto de competición, el sistema de tensor de cadena y el del acople de pinza de freno trasero. Junto a estos sistemas se diseñará, dada su relevancia, el basculante de la moto. Estos diseños se realizarán de tal manera que cumplan una serie de requisitos geométricos y de resistencia, garantizando en todo momento la estabilidad y seguridad del piloto. Se realizará también el estudio de la fabricación de cada uno de los elementos que componen los sistemas, con el fin de realizar diseños viables, que resulten económicamente factibles y mantengan un alto grado de calidad. En el proyecto se analizarán las diferentes alternativas de los sistemas que se puedan adoptar, sus ventajas y desventajas, para así poder escoger, con un alto grado de seguridad, la opción que mejor cumpla los objetivos y condiciones establecidos. Cabe destacar que este proyecto se encuentra dentro de otro de mayor envergadura consistente en el diseño y la fabricación de una motocicleta de competición para participar en el campeonato internacional llamado “MotoStudent”. Esta competición se realiza entre universidades de todo el mundo y en ella los equipos de estudiantes se enfrentan al desafío de diseñar y desarrollar un prototipo de motocicleta de competición similar a la categoría mundialista de “Moto3”.

Risk sensitivity in a motor task with speed-accuracy trade-off.

When a racing driver steers a car around a sharp bend, there is a trade-off between speed and accuracy, in that high speed can lead to a skid whereas a low speed increases lap time, both of which can adversely affect the driver's payoff function. While speed-accuracy trade-offs have been studied extensively, their susceptibility to risk sensitivity is much less understood, since most theories of motor control are risk neutral with respect to payoff, i.e., they only consider mean payoffs and ignore payoff variability. Here we investigate how individual risk attitudes impact a motor task that involves such a speed-accuracy trade-off. We designed an experiment where a target had to be hit and the reward (given in points) increased as a function of both subjects' endpoint accuracy and endpoint velocity. As faster movements lead to poorer endpoint accuracy, the variance of the reward increased for higher velocities. We tested subjects on two reward conditions that had the same mean reward but differed in the variance of the reward. A risk-neutral account predicts that subjects should only maximize the mean reward and hence perform identically in the two conditions. In contrast, we found that some (risk-averse) subjects chose to move with lower velocities and other (risk-seeking) subjects with higher velocities in the condition with higher reward variance (risk). This behavior is suboptimal with regard to maximizing the mean number of points but is in accordance with a risk-sensitive account of movement selection. Our study suggests that individual risk sensitivity is an important factor in motor tasks with speed-accuracy trade-offs.

Efficient minimum manoeuvre time optimisation of an oversteering vehicle at constant forward speed

A receding horizon steering controller is presented, capable of pushing an oversteering nonlinear vehicle model to its handling limit while travelling at constant forward speed. The controller is able to optimise the vehicle path, using a computationally efficient and robust technique, so that the vehicle progression along a track is maximised as a function of time. The resultant method forms part of the solution to the motor racing objective of minimising lap time. © 2011 AACC American Automatic Control Council.

Stability control of a railway vehicle using absolute stiffness and inerters

Work presented in this paper studies the potential of employing inerters -a novel mechanical device used successfully in racing cars- in active suspension configurations with the aim to enhance railway vehicle system performance. The particular element of research in this paper concerns railway wheelset lateral stability control. Controlled torques are applied to the wheelsets using the concept of absolute stiffness. The effects of a reduced set of arbitrary passive structures using springs, dampers and inerters integrated to the active solution are discussed. A multi-objective optimisation problem is defined for tuning the parameters of the proposed configurations. Finally, time domain simulations are assessed for the railway vehicle while negotiating a curved track. A simplification of the design problem for stability is attained with the integration of inerters to the active solutions. © 2012 IEEE.

Time-averaged velocity and turbulence intensity at the initial downstream flow from a six-bladed propeller

The current study investigated the time-averaged velocity and turbulence intensity at the initial downstream flow from a six-bladed ship propeller. The six-bladed propeller provided the rapid periodical pulses of thrust in one revolution due to the blades leading to a complex downstream jet. The six-bladed propeller is popular as a boat racing propeller, but the presentation of its flow structure was rarely found in the previous studies. In this study, the experiments were carried out in a water tank to measure the time-averaged velocity and turbulence intensity by using a Laser Doppler Anemometry (LDA) system. The jet was produced by rotating the propeller at a constant speed powered by an electric motor. The maximum tangential and radial velocities of the six-bladed propeller were of 76% and 17% of the maximum axial velocity respectively. The study found that the six-bladed propeller has a lower tangential velocity, but a higher radial velocity with its own diffusing mechanism when comparing to the three-bladed propeller.

Automaticity of cognitive biases in addictive behaviours: Further evidence with gamblers

Objectives. The hypotheses that automatic, non-volitional, attentional and memory biases for addiction-related constructs exist is tested with compulsive gamblers.

Design. An independent groups design was employed. Processing of gambling, compared to neutral and drug-related information was examined in 15 gamblers recruited from new members of Gamblers Anonymous. Comparisons were made with the performance of their spouses (N = 15) to help distinguish addiction mechanisms from more non-specific emotional experiences with gambling, and an independent control group (N = 15), recruited from the staff and students of a university department.

Methods. A modified Stroop procedure was first employed. Automative cognitive interference was assessed relatively, by comparing colour-naming times on the gambling, drug and neutral Stroops. A subsequent word-stem completion task of implicit memory was then used to assess selective and automatic priming of the gambling constructs in memory.

Results. Only the gamblers showed selective and automatic interference for gambling-related constructs on the Stroop task. Spouses behaved like the control group on this task. An implicit memory bias for gambling-related words was statistically detected only in the gamblers compared to the control group, although the trend was similar in the comparison with spouses. Further evidence for the specificity of these effects was obtained in subgroup comparisons involving fruit-machine with racing gamblers.

Conclusions. Results are generally consistent with an automaticity in the cognitive biases gamblers show for gambling-related information. implications for cognitive understanding and treatments are highlighted.

Improving the Fuel Economy of a Tuned 600cc FSAE Engine

To maintain its relevance, motorsport cannot be exempt from
the trend of increasing fuel economy. This bears obvious
competitive benefits as well, either in decreasing the
frequency of pit stops or the mass of fuel carried. Given the
increased points weighting of fuel economy for the Formula
Student (FS) competition, a complete analysis was performed
on the Queen's Formula Racing 600cc motorcycle engine in
preparation for the 2011 competition.
The criteria for such high performance fuel economy differ to
a degree from most mass transportation counterparts and were
divided into three distinct regimes; full load, part load and no
load conditions.
Full load positions naturally demand maximum torque for
performance but that does not imply that fuel savings cannot
be made whilst preserving this. The point at which maximum
torque is produced with minimum air -fuel ratio, Leanest
mixture for Best Torque (LBT), was therefore sought and
mapped for full load.
At part load, torque is less of a concern, and maintaining a
sustainable engine temperature and transient response become
more important. With decreasing AFR, engine temperatures
can rise dramatically so temperatures were measured close to
the exhaust port for a wide range of air-fuel ratios.
Competition track data was analysed to highlight key part load
operating regions and these were mapped according to
measured safe temperature limits. Torque response to a step
throttle change was also measured to ensure suitable engine
transient performance was maintained.
At no load conditions, with low engine speed only idle
conditions need to be satisfied. In the situation where the
engine is still at high speed without load, the engine is being
motored and no fuel is required. An overrun fuel cut was
employed to reflect this giving significant fuel savings. The
effect on torque and engine pickup was measured.
Modifications were also made to the fuel injector location to
improve fuel mixing and evaporation at this lower air flow
condition.
These mapping regimes were implemented and tested using
fully transient lap simulations using competition track data
and a four quadrant AC engine dynamometer. The experiment
indicated a reduction in fuel consumption for 22 laps of the FS
track from 5.08litres to 3.67litres, around 27% in total. The
actual fuel used at the 2011 competition was 3.6 litres while
placing 8th in the endurance event, further validating the
benefits of these mapping regimes.

Sporting Justice: An Arbitrator's Perspective

Drawing on my experience of a number of sports dispute resolution tribunals in the UK and Ireland (such as Sports Resolutions UK; Just Sport Ireland; the Football Association of Ireland’s Disciplinary Panel and the Gaelic Athletic Association’s Dispute Resolution Authority) I intend to use this paper to review the legal arguments typically made in sports-related arbitrations. These points of interest can be summarised as a series of three questions: the fairness question; the liability question; the penalty question.

In answer to the fairness question, the aim is to give a brief outline on best practice in establishing a "fair" sports disciplinary tribunal. The answer, I believe, is always twofold in nature: first, and to paraphrase Lord Steyn in R v Secretary of State For The Home Department, Ex Parte Daly [2001] UKHL 26 at [28] "in law, context is everything" – translated into the present matter, this means that in sports disciplinary cases, the more serious the charges against the individual (in terms of reputational damage, economic impact and/or length of sanction); the more tightly wrapped the procedural safeguards surrounding any subsequent disciplinary hearing must be. A fair disciplinary system will be discussed in the context of the principles laid down in Article 8 of the World Anti-Doping Code which, in effect, acts as sport’s Article 6 of the ECHR on a right to a fair trial.

Following on from the above, in the 60 or so sports arbitrations that I have heard, there are two further points of interest. First, the claim before the arbitral panel will often be framed in an argument that, for various reasons of substantive and procedural irregularity, the sanction imposed on the appellant should be quashed ("the liability"). Second, and in alternative, that the sanction imposed was wholly disproportionate ("the penalty").

The liability issue usually breaks down into two further questions. First, what is the nature of the legal duty upon a sports body in exercising its disciplinary remit? Second, to what extent does a de novo hearing on appeal cure any apparent defects in a hearing of first instance? The first issue often results in an arbitral panel debating the contra preferentum approach to the interpretation of a contested rule i.e., the sports body’s rules in question are so ambiguous that they should be interpreted in a manner to the detriment of the rule maker and in favour of the appellant. On the second matter, it now appears to be a general principle of sports law, administrative law and even human rights law that even if a violation of the principles of natural justice takes place at the first instance stage of a disciplinary process, they may be cured on de novo appeal. Authority for this approach can be found at the Court of Arbitration for Sport and in particular in CAS 2009/A/1920 FK Pobeda, Aleksandar Zabrcanec, Nikolce Zdraveski v UEFA at para 87.

The question on proportionality asks what, aside from precedent found within the decisions of the sports body in question, are the general legal principles against which a sanction by a sports disciplinary body can be benchmarked in order to ascertain whether it is disproportionate in length or even irrational in nature?

On the matter of (dis)proportionality of sanction, the debate is usually guided by the authority in Bradley v the Jockey Club [2004] EWHC 2164 (QB) and affirmed at [2005] EWCA Civ 1056. The Bradley principles on proportionality of sports-specific sanctions, recently cited with approval at the Court of Arbitration for Sport, will be examined in this presentation.

Finally, an interesting application of many of the above principles (and others such as the appropriate standard of proof in sports disciplinary procedures) can be made to recent match-fixing or corruption related hearings held by the British Horse Racing Authority, the integrity units of snooker and tennis, and at the Court of Arbitration for Sport.

The effect of the 'Gait keeper' mutation in the DMRT3 gene on gaiting ability in Icelandic horses

A nonsense mutation in DMRT3 ('Gait keeper' mutation) has a predominant effect on gaiting ability in horses, being permissive for the ability to perform lateral gaits and having a favourable effect on speed capacity in trot. The DMRT3 mutant allele (A) has been found in high frequency in gaited breeds and breeds bred for harness racing, while other horse breeds were homozygous for the wild-type allele (C). The aim of this study was to evaluate further the effect of the DMRT3 nonsense mutation on the gait quality and speed capacity in the multigaited Icelandic horse and demonstrate how the frequencies of the A- and C- alleles have changed in the Icelandic horse population in recent decades. It was confirmed that homozygosity for the DMRT3 nonsense mutation relates to the ability to pace. It further had a favourable effect on scores in breeding field tests for the lateral gait tölt, demonstrated by better beat quality, speed capacity and suppleness. Horses with the CA genotype had on the other hand significantly higher scores for walk, trot, canter and gallop, and they performed better beat and suspension in trot and gallop. These results indicate that the AA genotype reinforces the coordination of ipsilateral legs, with the subsequent negative effect on the synchronized movement of diagonal legs compared with the CA genotype. The frequency of the A-allele has increased in recent decades with a corresponding decrease in the frequency of the C-allele. The estimated frequency of the A-allele in the Icelandic horse population in 2012 was 0.94. Selective breeding for lateral gaits in the Icelandic horse population has apparently altered the frequency of DMRT3 genotypes with a predicted loss of the C-allele in relatively few years. The results have practical implications for breeding and training of Icelandic horses and other gaited horse breeds.

Graffiti composition: screenplay

Ongoing collaboration with Christian Marclay. ‘Graffiti Composition’ and ‘Screenplay’ are two related works consisting of live musical improvisation and performance. They are part of an ongoing collaboration with the artist Christian Marclay. 'Graffiti Composition' involved Beresford directing an invited orchestra of improvising musicians. The work focuses on making music from the random compositional acts of strangers. Prior to realization, Marclay fly-posted several hundred sheets of blank manuscript paper, collecting the sheets some days later, after passers-by had written on them – using either traditional music notation or more transgressive interference modes (colour-blocks, torn holes in or abstract graphic symbols on the paper) – and sending photographs of them to Beresford. Beresford’s directorial decisions helped these random graffiti become music via simple formal processes – restricting each musician to a handout of two MS each, or stipulating a mini-concerto for each player. Beresford’s contribution explores the paradox of improvisation stipulated by strangers and controlled, however loosely, by the structuring agency of a musical director. ‘Screenplay’ extended this collaborative process between Marclay and Beresford. Beresford and other musicians responding to a visual track comprising found and public domain moving images manipulated by Marclay – gunfight scenes from a TV Western; running water; racing cars morphing into crying children, and so on, in black-and-white, with single-colour blocks appearing and developing as lines, spots, and other suggestive ‘notation’. The elliptical, surprising, humorous nature of the images at times is hyperexplicated by the improvised music, and at others challenged, ignored or contradicted by the musicians’ interaction. ‘Graffiti Composition’ was performed by the LSO at St. Luke’s, London, March 22, 2005. ‘Screenplay’ premiered in Dundee in 2006, and toured Europe during 2007. Reviewed in the Herald (21 Feb 06) and Times (24 March 07). Beresford’s work as improviser, composer and performer was profiled in The Wire (April 2002, May 2005).