Laura Justham

Accelerometer Profile Recognition of Swimming Strokes (P17)

The use of technology in sports performance analysis is a rapidly increasing practise. Tools for analysis aim to provide useful information to supplement coach knowledge and improve feedback in the development of athletes. In swimming the use of subjective video analysis is wide-spread, however, unlike some other sports, there are few quantitative measures of performance. Quantitative measures, such as intra cyclic variations of stroke characteristics, have the potential to provide more specific performance metrics from which to make improvements. Such measures are currently not widely available to coaches, support staff and swimmers, due to the infancy or lack of sufficiently developed technologies.

Stability of martensitic domains in the ferromagnetic alloy Ni2MnGa: a mechanism for shape memory behaviour

The martensitic phase transition in Ni2MnGa, fundamental to its shape memory behaviour, can be described by two successive 110 type shears leading to 36 possible different orientations for the axes of the pseudo-tetragonal martensitic phase. The distribution and orientation of the domains formed on cooling Ni2MnGa into the martensitic phase has been studied using single-crystal neutron diffraction with a multi-detector. The number of domains actually occurring was rather low and was reduced by residual strain. Thermal cycling through the phase transition was found to further reduce the number of domains occurring, which may stabilize after several cycles. Uniaxial stress or a magnetic field applied parallel to [001] is able to switch domains whose pseudo-tetragonal axis is [100] or [010] to ones of type [001]. The results suggest that plastic deformation in the martensitic phase takes place by twinning (change of domain), rather than by slip and that the shape memory property arises from the fixed orientation relationship between the martensitic twins and the high temperature cubic axes.

Investigation of relationship between interfacial electroadhesive force and surface texture

A novel investigation into the relationship between the obtainable interfacial electroadhesive forces and different surface textures is presented in this paper. Different surface textures were generated then characterized based on a recognized areal-based non-contact surface texture measurement platform and procedure. An advanced electroadhesive force measurement platform and procedure were then implemented to measure the obtainable electroadhesive forces on those different surface textures. The results show that the obtained interfacial electroadhesive forces increase with decreasing Sq (root mean square height) value of the substrate surface provided that the difference in Sq between the different substrates is over 5 μm. Also, the higher the applied voltage, the larger the relative increase in electroadhesive forces observed. However, when the difference of Sq value between different substrate surfaces is below 2 μm, the obtained interfacial electroadhesive forces do not necessarily increase with decreasing Sq. Furthermore, the obtainable electroadhesive forces are not necessarily the same when the Sq value of two substrate surfaces are the same due to the fact that the direction of the surface texture plays an important role in achieving electroadhesive forces.

Three-dimensional vision analysis to measure the release characteristics of elite bowlers in cricket:

Cricket is a sport played internationally in over 100 countries. Two teams face one another in a match, each taking it in turns to bat and field. In the fielding side, bowlers deliver the ball to the batsman who then responds by hitting the ball away. Batting and bowling are complex and dynamic skills which must be practised at length in training. However, due to the demanding nature of bowling, batsmen can train against a machine to face sufficient numbers of deliveries. An advanced training machine is under development at Loughborough University that is capable of delivering technically correct bowling deliveries in a repeatable manner. However, in order to monitor that the machine is generating accurate deliveries, a study to quantify the variability in the delivery parameters of bowlers has been undertaken, and the results are presented in this paper. Eight spin bowlers and ten pace bowlers have been studied. Each bowler was asked to deliver up to five balls, and the results have been analysed and presented. It has been found that the range of ball release speed varies from 17.5–35.0 m/s, the rate of spin imparted by the bowler varies from 11.44–231.22 rad/s, the launch angle of the ball varies from 9.7° above the horizontal to 19.2° below the horizontal and the launch position on the wicket varies from 1.97–2.38 m in height, ±1.95 m in width and 0.36–1.79 m from the bowler’s stumps.

New lifecycle monitoring system for electronic manufacturing with embedded wireless components

Purpose – The purpose of this paper is to present an update of and the latest results from work on a project aimed at monitoring electronic products during the whole life cycle with embedded wireless components.Design/methodology/approach – Business processes of the electronic manufacturing supply chain were analysed. A business case and the system opportunities for life cycle monitoring, based on embedded wireless components system were developed. Radio frequency identification (RFID) assembly technology was adapted for the integration of components into a multi‐layer printed circuit board (PCB).Findings – By storing product‐related information into electronic products, tracing of components, monitoring of processes, operations and costs, environmentally optimised recycling can be enhanced.Research limitations/implications – The research undertaken so far relates to the embedding of RFID tags into PCBs. Wireless components with more processing power will be used in the next project phase.Originality/valu...

Optimization and experimental verification of coplanar interdigital electroadhesives

A simplified and novel theoretical model for coplanar interdigital electroadhesives has been presented in this paper. The model has been verified based on a mechatronic and reconfigurable testing platform, and a repeatable testing procedure. The theoretical results have shown that, for interdigital electroadhesive pads to achieve the maximum electroadhesive forces on non-conductive substrates, there is an optimum electrode width/space between electrodes (width/space) ratio, approximately 1.8. On conductive substrates, however, the width/space ratio should be as large as possible. The 2D electrostatic simulation results have shown that, the optimum ratio is significantly affected by the existence of the air gap and substrate thickness variation. A novel analysis of the force between the electroadhesive pad and the substrate has highlighted the inappropriateness to derive the normal forces by the division of the measured shear forces and the friction coefficients. In addition, the electroadhesive forces obtained in a 5 d period in an ambient environment have highlighted the importance of controlling the environment when testing the pads to validate the models. Based on the confident experimental platform and procedure, the results obtained have validated the theoretical results. The results are useful insights for the investigation into environmentally stable and optimized electroadhesives.

A Concept Selection Method for Designing Climbing Robots

This paper presents a concept selection methodology, inspired by the Verein Deutscher Ingenieure (VDI) model and Pughs weighted matrix method, for designing climbing robots conceptually based on an up-to-date literature review. The proposed method is illustrated with a case study of ongoing research, the investigation of an adaptable and energetically autonomous climbing robot, in Loughborough University.

Quantification and characterization of cricket bowling technique for the development of the parameters required for a novel training system for cricket

Cricket bowling has traditionally been referenced using ball release speed, and existing classifications consider the four major bowling types as fast, fast—medium, medium, and spin. A research project based at Loughborough University has recognized the need for an extended bowling classification that not only considers the ball speed, but also its initial flight characteristics, including any spin imparted at release. The purpose of this paper has been the development of an extended bowling classification, which has been used in the development of a requirements specification for an advanced ball delivery system for cricket, to ensure the accurate recreation of technically correct bowling deliveries. Data collected during training and match play have been used to define bowling quantitatively. The initial ball flight characteristics of 30 elite-level bowlers have been filmed in training using a Photron FASTCAM ultima APX high-speed video camera. These videos have been used to determine the speed, the rate of spin, and the initial flight trajectory of the ball at release. Additionally, Hawk-Eye ball-tracking software has been used to investigate the full flight characteristics of seven elite bowlers during a five Test match series.

Feature extraction and tracking of a weld joint for adaptive robotic welding

Recent advances in automation and sensor technology have enabled the use of industrial robots for complex tasks that require intelligent decision making. Vision sensors have been the most successfully used sensor in many high value industrial applications. Over the recent years, weld seam tracking has been a topic of interest, as most of the existing robotic welding systems operate on basis of pre-programmed instructions. Such automated systems are incapable of adapting to unexpected variations in the seam trajectory or part fit-up. Applications such as tungsten inert gas (TIG) welding of aerospace components require high tolerances and needs intelligent decision making. Such decision making procedure has to be based on the weld groove geometry at any instance. In this study, a novel algorithm along with an automated system was developed for estimating the joint profile and path tracking of a three dimensional (3D) weld groove. A real-time position based closed-loop system was developed with a six axis industrial robot and a laser triangulation based sensor. The system was capable of finding the 3D weld joint profile and position in real-time, and make intelligent decisions accordingly. Raw data from a vision sensor was processed through a novel algorithm to obtain X and Z co-ordinates at an accuracy of 8.3μm and 43μm respectively at an acquisition speed of 2.5 profiles per second. The algorithm was also capable of measuring the weld gaps with an accuracy of 28μm. Finally, the developed system was successfully used for three dimensional seam tracking, and demonstrates an accuracy of ±0.5mm at a tracking a speed of 2mm/s.

Design and development of a novel, integrated bowling machine for cricket

Bowling machines are used in cricket training to improve a batsmans technique and prevent injury or fatigue to the bowler through overuse; however, existing bowling machines do not provide a realistic training environment that compares to the experience of facing a real bowler. This paper presents the design process undertaken to specify a novel bowling machine which is capable of recreating all common types of technically correct bowling deliveries. The design was implemented based on the requirements and specifications outlined by cricket coaches and players. A prototype was then manufactured and tested thoroughly in the laboratory and at the England and Wales Cricket Boards National Cricket Centre at Loughborough University. Results obtained have shown that the novel bowling machine is capable of recreating realistic bowling deliveries with the correct spin and speed characteristics.