HSRS is taken as a typical research case of large-scale complex nonlinear systems, and the re-innovation of associated imported technologies needs to be combined with the particularities of Chinese HSR practices, seeking a more suitable dynamic design methodology to conduct the self-adaptive improved design. Different from the troublesomeness of the primary hunting phenomenon, the self-adaptive improved design can decrease considerably the impact of car body instability on ride comfort merely by applying the semiactive damping technique between intervehicles, to promote scientifically the limit and construction speeds under the rational conditions of wheel-rail matching, i.e., λeN ≥ λemin, λemin = (0.03–0.05). The researching viewpoint of hunting kinematics makes the investigations on the geometric nonlinearity of the wheel-rail contacts contrary to the hypothesis of small creepage and no spin. Since the technical prototype of German ICE3 serial bogies has the design default of the primary hunting phenomenon, the improved design of the wheel-rail relationship has simply abandoned the high-quality technical resources of wheel-rail matching conditions at low conicity. On the contrary, the dynamic simulation analyses of MC01-TC02-MC03 three-vehicles trainset show that the semiactive damping technique between intervehicles takes advantage of Izz >> Ixx to improve the impacts of car body instability on ride comfort, and the self-adaptive improved design has consequently the ability to achieve the technical goal of uniform wear at low conicity. On the premise of meeting the requirements of crossing over different speed grade dedicated lines and realizing the running operations on three-speed levels of 160/250/350 km/h, the self-adaptive higher-/high-speed bogies can conditionally satisfy the economic reprofiling requirements of wheelsets through the optimal routing planning.

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For high-tech manufacturing industries, developing large-scale complex nonlinear dynamic systems must be taken as one of the basic works, formulating problems to be solved, steering system design in a more preferable direction, and making correct strategic decisions. By using effective tools of big data mining, Dynamic Design Methodology was proposed to establish a technical platform for Multidiscipline Design Optimization such as High-Speed Rolling Stock, including three key technologies: analysis graph of full-vehicle stability properties and variation patterns, improved transaction strategy of flexible body to MBS interface, seamless collaboration with weldline fatigue damage assessments through correct Modal Stress Recovery. By applying the above methodology, a self-adaptive improved solution was formulated with optimal parameter configuration, which is one of the more favorable options for higher-speed bogies. While within a velocity (140–200) km/h at λe < 0.10, car body instability’s influence on ride comfort can be easily improved by using a semi-active vibration reduction technique between inter-vehicles through outer windshields. Comprehensive evaluations show that only under rational conditions of wheel-rail matching, i.e., 0.10 ≥ λeN > λemin and λemin = (0.03–0.06), can this low-cost solution achieve the three goals of low track conicity, optimal route planning, and investment benefit maximization. So, rail vehicle experts are necessary to collaborate and innovate intensively with passenger transportation and steel rail ones. Specifically, by adopting rail grinding treatment, occurrence probability is controlled at 85% and 5% for track conicity of (0.03–0.10) and (0.25–0.35). By optimizing routing planning, operating across dedicated lines of different speed grades can achieve self-cleaning of central hollow tread wear over time. According to the inherent rigid-flex coupling relationship, geometric nonlinearities of worn wheel-rail contact should be avoided as much as possible for HSR practices. Only under weak coupling interfaces in the floor frame can the structural integrity of an aluminum alloy car body be ensured.

For hi-tech manufacturing industries, developing large-scale complex nonlinear dynamic system must be taken as one of basic works, formulating problems to be solved, steering system design to a more preferable direction, and making correct strategic decisions. By using effective tools of big data mining, Dynamic Design Methodology was proposed to establish technical platform of Multidiscipline Design Optimization such as High Speed Rolling Stock, including three key technologies: i) Analysis graph of full-vehicle stability properties and variation patterns, providing instructive guidance on optimal parameter configuration of self-adaptive improved design for higher speed bogies to reduce track force; ii) Improved transaction strategy of flexible body to MBS interface, making boundary loading treatments more subtle to implement weak coupling interface of aluminium alloy car body to equipment cabin under floor frame; iii) Seamless collaboration with weldline fatigue damage assessments, ensuring structure integrity via correct Modal Stress Recovery. Steel rail profession unilaterally initiated improved design of wheel-rail relationship, which is proved to be unfavourable to commercial applications for Chinese High Speed Rails. On first fluttering phenomenon of service car body, contrastive analyses of line tracking tests and rigid-flex coupling simulations show that internal lateral coupling resonance of such as traction converter has been one of main restrictive factors that determine cost effectiveness. Whilst self-adaptive improved solution is one of more favourable options. Comprehensive evaluations show that only under rational conditions of wheel-rail matching, i.e. 0.10 ≥ λeN > λemin and λemin= (0.03–0.06), can this low cast solution achieve three goals of low track conicity, optimal route planning and investment benefit maximization.