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Since most people now have a high-performing computing device with an attached camera in their pocket, in the form of a smartphone, robotics and computer vision researchers are thrilled about the possibility this creates. Such devices have previously been used in robotics to create 3D maps of environments and objects by feeding the camera data to a 3D reconstruction algorithm. The big downside with smartphones is that their cameras use a different sensor than what is usually used in robotics, namely a rolling shutter camera.These cameras are cheaper to produce but are not as well suited for general 3D reconstruction algorithms as the global shutter cameras typically used in robotics research. One recent, accurate and performance effective 3D reconstruction method which could be used on a mobile device, if tweaked, is LSD-SLAM. This thesis uses the LSD-SLAM method developed for global shutter cameras and incorporates additional methods developed allow the usage of rolling shutter data.The developed method is evaluated by calculating numbers of failed 3D reconstructions before a successful one is obtained when using rolling shutter data.The result is a method which improves this metric with about 70\% compared to the unedited LSD-SLAM method.

Initial investigations were conducted to determine the feasibility of applying a post solution heat treatment stress relief stretching operation to near-net-shaped taper rolled aerospace aluminium plate, in terms of the possible process window and the impact on key mechanical properties. Finite element modelling (FEM) and simulations, validated using digital image correlation to measure the strain distribution in flat tapered tensile specimens, have demonstrated the existence of a suitable process window for the production of near-net-shape wing skin blanks. It was revealed that the limits of the available taper geometry are dictated by the work hardening behaviour of the specific aluminium alloy. In addition, in the case of two typical upper wing skin alloys AA2195 and AA7055, tensile and toughness testing revealed that the resultant strain gradient offers the potential for graded mechanical properties suited to this application, with a higher level of toughness at the wing root and an increase in the yield strength of the material at the wing tip. Further, investigations explore the effect of increased tensile pre-stretching, to the maximum achievable before tensile instability, on the strength, microstructure, and precipitation kinetics seen during ageing alloys AA2195 and AA7055. Subsequently, in both alloys, microstructure data have been used to deconvolute and model the effects of increasing pre-strain on the main strengthening components that contribute to the T8 yield strength of the material. In the case of the AA2195 alloy, the T8 yield strength was observed to increase continually as a function of pre-strain to a maximum value of ~670MPa at 15%. It was shown that refinement of the T1 phase continued to the maximum obtainable pre-strain, which was predicted to result in a reduction in the precipitate strengthening contribution. The increase in the T8 yield strength resulting from high levels of pre-strain was attributed to a large increase in residual strain hardening following artificial ageing, owing to a low level of recovery. In the AA7055 alloy, increased pre-strain led to a substantial increase in the T3 yield strength, which was revealed to be due to the dynamic precipitation of GP-Zones. In the T8 temper the yield strength of the alloy increased continually as a function of pre-strain to a maximum of ~607MPa at 24%. Increasing pre-strain was shown to result in a continual and significant increase in the residual strain hardening contribution to the alloys T8 yield strength, due to the occurrence of limited recovery. However, it was also shown that increasing pre-strain led to a progressive reduction in the precipitate strengthening contribution from the eta prime phase, due to an increase in the volume fraction of precipitate free zones (PFZs) with increased dislocation density. Therefore, the increase in the T8 yield strength, as a function of pre-strain, is attributed to an increased residual strain hardening contribution which outweighs a smaller progressive reduction in the precipitate strengthening contribution.

Mobile robots for rough terrain are of interest to researchers as their range of possible uses is large, including exploration activities for inhospitable areas on Earth and on other planets and bodies in the solar system, searching in disaster sites for survivors, and performing surveillance for military applications. Nature generally achieves land movement by walking using legs, but additional modes such as climbing, jumping and rolling are all produced from legs as well. Robotics tends not to use this integrated approach and adds additional mechanisms to achieve additional movements. The spherical device described within this thesis, called Jollbot, integrated a rolling motion for faster movement over smoother terrain, with a jumping movement for rougher environments. Jollbot was developed over three prototypes. The first achieved pause-and-leap style jumps by slowly storing strain energy within the metal elements of a spherical structure using an internal mechanism to deform the sphere. A jump was produced when this stored energy was rapidly released. The second prototype achieved greater jump heights using a similar structure, and added direction control to each jump by moving its centre of gravity around the polar axis of the sphere. The final prototype successfully combined rolling (at a speed of 0.7 m/s, up 4° slopes, and over 44 mm obstacles) and jumping (0.5 m cleared height), both with direction control, using a 0.6 m spherical spring steel structure. Rolling was achieved by moving the centre of gravity outside of the sphere’s contact area with the ground. Jumping was achieved by deflecting the sphere in a similar method to the first and second prototypes, but through a larger percentage deflection. An evaluation of existing rough terrain robots is made possible through the development of a five-step scoring system that produces a single numerical performance score. The system is used to evaluate the performance of Jollbot.

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A general approach to numerically simulating wear in rollingand sliding contacts is presented in this thesis. A simulationscheme is developed that calculates the wear at a detailedlevel. The removal of material follows Archard’s wear law,which states that the reduction of volume is linearlyproportional to the sliding distance, the normal load and thewear coefficient. The target application is the wheel-railcontact. Careful attention is paid to stress properties in the normaldirection of the contact. A Winkler method is used to calculatethe normal pressure. The model is calibrated either withresults from Finite Element simulations (which can include aplastic material model) or a linear-elastic contact model. Thetangential tractions and the sliding distances are calculatedusing a method that incorporates the effect of rigid bodymotion and tangential deformations in the contact zone.Kalker’s Fastsim code is used to validate the tangentialcalculation method. Results of three different sorts ofexperiments (full-scale, pin-on-disc and disc-on-disc) wereused to establish the wear and friction coefficients underdifferent operating conditions. The experimental results show that the sliding velocity andcontact pressure in the contact situation strongly influencethe wear coefficient. For the disc-on-disc simulation, therewas good agreement between experimental results and thesimulation in terms of wear and rolling friction underdifferent operating conditions. Good agreement was alsoobtained in regard to form change of the rollers. In thefull-scale simulations, a two-point contact was analysed wherethe differences between the contacts on rail-head to wheeltread and rail edge to wheel flange can be attributed primarilyto the relative velocity differences in regard to bothmagnitude and direction. Good qualitative agreement was foundbetween the simulated wear rate and the full-scale test resultsat different contact conditions. <b>Keywords:</b>railway rail, disc-on-disc, pin-on-disc,Archard, wear simulation, Winkler, rolling, sliding

Since oil-in-water emulsions combine good cooling and lubricating capabilities, they have been commonly used in cold rolling nowadays. In order to understand the tribology characteristics of the emulsion during the cold rolling process, the effects of load, sliding speed, material of specimen, surface roughness and type of emulsion on the tribology characteristics of cold rolling are investigated by using the multi-purpose friction and wear tester.The P (load) ¡VV (sliding speed) curve was investigated under the conditions of load (below 2.4GPa), sliding speed (below 2.2m/s) at lower specimen roughness. Results show that QK-N36 emulsion can differentiate between boundary lubrication regime and initial seizure according to their friction coefficient, but RL-61 emulsion cannot differentiate them. Therefore, the load carrying capacity of RL-61 emulsion is better than that of QK-N36 emulsion, and its friction coefficient is also lower than that of QK-N36 emulsion. However, this tendency of experimental results is different from the cold-rolling practice.Under the lower load and higher surface roughness conditions with different hardness of specimen, the friction coefficient of RL-61 emulsion is higher than that of QK-N36 emulsion. This tendency of experimental results is the same as the rolling practice. Under the lower load condition with SDK-11 specimen, the friction coefficient of RL-61 emulsion varies gradually in the range of 0.07 ~ 0.09 located in the boundary lubrication regime, but the friction coefficient of QK-N36 emulsion reduces to 0.02~0.04 located in the mixed lubrication regime.

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In this research the stochastic nonlinear dynamic behaviors and probability density function of ship rolling are studied by nonlinear dynamic method and probability theory. The probability density function of rolling response is evaluated through solving the stochastic differential equations by using path integral method based on Gauss-Legendre interpolation scheme. The time-dependent probability of ship rolling restricted within the safe domain is provided and capsizing is investigated in the probability‟s view. The random differential equation of ships‟ rolling motion is established considering the nonlinear damping, nonlinear restoring moment, the white noise wave excitation, and the colored noise wave excitation. As an example, an ocean survey vessel T-AGOS is considered to sail in the seas of Pierson-Moskowitz wave spectrum. It is found that the probability decreases as time progresses and it decreases much more quickly for the high intensity of the noise. The ship will finally leave the safe domain and capsize in the probability‟s view. It is also shown the similarity of probability density contours between the case of white noise wave excitation and the case of colored noise wave excitation.

Abstract The rolling is an efficient and economical approach for the manufacturing of strip or plate metals, it plays an important role because of its versatility and its high production rate in the manufacture of various products with uniform cross-sectional area. Without the knowledge of the influences of the variables such as friction conditions, material properties, and workpiece geometry on the process mechanics, it will not be possible to design and control the equipment adequately, or to predict and prevent the occurrence of failures. According to modeling by numerical has become a major tool in rolling research. By using the proper criterion, de-pending upon the production requirements along with the modeling results, the process efficiency, productivity and quality can be increased and the down time of the mill and cost operation can be reduced. In this study, investigated that it do not consider to work hardening and consider to work hardening during the rolling process from Von Karman theory. We can realize friction coefficient, reduction ratio, rolling force, rolling torque, neutral point, and pressure distribution relation, then from measuring rolling force, torque, neutral point can inverse to solve friction coefficient and pressure distribution. Result that we found the error of direct and inverse solution about rolling friction coefficient was less than 5 %, and the coef-ficient of friction was found to increase with reduction and rolling force and neutral point.