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A novel structure design method to improve the output performance in course of modular robot is presented in this paper. The new design parameter of modular joint is defined based on analysis of existing joint. Output torque and Max speed is increased by means of different Brushless DC-Servomotor and harmonic reducer in limited interspace. The repeated positioning accuracy is not reduced when output torque and Max speed are increased. And parts of the process parameters is improved. The new design parameters show that the design method is feasible.

In order to improve the response effectiveness, extend the workspace of parallel manipulator and make it more conveniently to be used in realistic tasks, this paper has introduced an improved mechanism based on the traditional 6-PUS, which applied the rails leaning outside and the linear motor as its driving system. This has optimized the initial parameters of the improved mechanism, and analyzed its workspace in the software Matlab using the method of cylindrical coordinate search. The result has a guiding significance in optimization of traditional parallel manipulators and the manufacturing of the new prototype.

In order to establish a flexible squirm pipe robot’s mechanical model and find an appropriate method to improve its moving performance, the working qualifications and dynamic analysis of brake wheels are made. Proceed with the robot's moving mechanism, the squirm principle and mechanical qualifications of the robot’s brake wheels are analyzed, and the model of the robot’s traction is derived. Based on that, the prototype is made. Finally, the validity of the design and theories is verified by experiments.

This study develops a generalised multi‐hazard analysis framework for evaluating the impact of secondary hazard events on structures that have previously been damaged by major hazardous events. More specifically, the present work investigates the effects of thunderstorm downbursts on earthquake‐damaged tall steel buildings giving an emphasis in assessing the revised accumulated earthquake‐wind ductility demands. The novel approach is validated on a 20‐storey steel building. The structure is initially subjected to a ductility‐controlled pushover analysis to simulate the earthquake‐induced damage, and then, a parametric dynamic analysis is performed using damaged structure models under synthetic downburst time‐histories developed for various wind profiles, wind velocities and terrain types. The method accurately controls the damage level induced by the primary hazard and separately assesses secondary hazard effects which enables a direct quantification of the new multi‐hazard design requirements. This can provide effective guidance in the stage of preliminary structural design or post‐hazard assessment of structures identifying new serviceability limits, as well as support repair procedures and decision‐making frameworks for existing structures to prevent collapse. The results demonstrate a significant increase up to three to four times in ductility demands of the structure after the occurrence of the strong downburst winds, compared with the ductility demands that were initially imposed by the varying severity degrees of the earthquake.