Abstract.Starting from an existing advanced motorcycle dynamics model, which allows simulation of reasonably general motions and stability, modal and response computations for small perturbations from any trim condition, improvements are described. These concern (a) tyre/road contact geometry, (b) tyre shear force and moment descriptions, as functions of load, slip and camber, (c) tyre relaxation properties, (d) a new analytic treatment of the monoshock rear suspension mechanism with sample results, (e) parameter values describing a contemporary high performance machine and rider, (f) steady-state equilibrium and power checking and (g) steering control. In particular, the "Magic Formula" motorcycle tyre model is utilised and complete sets of parameter values for contemporary tyres are derived by identification methods. The new model is used for steady turning, stability, design parameter sensitivity and response to road forcing calculations. The results show the predictions of the model to be in general agreement with observations of motorcycle behaviour from the field and they suggest that frame flexibility remains an important design and analysis area, despite improvements in frame designs over recent years. Motorcycle rider parameters have significant influences on the behaviour, with results consistent with a commonly held view, that lightweight riders are more likely to suffer oscillation problems than heavyweight ones.

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Abstract-This paper develops an indirect optimal control methodology to achieve green driving optimisation for series hybrid electric vehicles. Starting from a given vehicle mission, specified in terms of a road journey that has to be completed in a given amount of time, the power sharing among the powertrain sources and the vehicle speed profile along the journey are optimised and found. The scheme combines parametric modelling of the vehicle and powertrain together with computationally efficient optimal control software to provide an optimization strategy that works in real-time. Simulation results that demonstrate the success of the method and provide further insight into efficient driving, are presented.

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A comprehensive study of the eVects of acceleration and braking on motorcycle stability is presented. This work is based on a modi®ed version of a dynamic model presented earlier, and is thought to be the most comprehensive motorcycle dynamic model in the public domain. Extensive use is made of both non-linear and linearized models. The models are written in LISP and make use of the multibody modelling package AUTOSIM. There is novelty in the way in which control systems have been used to control the motorcycle drive and braking systems in order that the machine maintains desired rates of acceleration and deceleration.The results show that the wobble mode of a motorcycle is signi®cantly destabilized when the machine is descending an incline or braking on a level surface. Conversely, the damping of the wobble mode is substantially increased when the machine is ascending an incline at constant speed, or accelerating on a level surface. This probably accounts for the pleasingly stable`feel' of the machine under ®rm acceleration.Except at very low speeds, inclines, acceleration and deceleration appear to have little eVect on the damping or frequency of the weave mode. Non-linear simulations have quanti®ed the known di culties to do with rear tyre adhesion in heavy braking situations that are dominated by rear wheel braking.

11.11.14 KB. Ok to add accepted version to spiral, subject to 12 months embargo (published online 21 Sept 2014

Abstract-A new family of electro-mechanical active suspensions that offers significant advantages with respect to passive and semi-active suspensions, while at the same time avoiding the main disadvantages of alternative active solutions, is presented in this paper. The Series Active Variable Geometry Suspension takes a conventional independent passive or semi-active suspension as its starting point, and improves its behavior by actively controlling the suspension geometry with an electro-mechanical actuator. The advantages of this type of suspension are discussed and its simplest variant is studied in detail. Insight on the design process, as well as on the actuator modeling and selection is provided. Moreover, a control system for pitch attitude control of the chassis is presented. Simulation results obtained with a high-fidelity, fullvehicle, non-linear model of a high performance sports car that includes actuator dynamics and saturation limits are shown to confirm the potential of the proposed system.