Considering that impact motion is not only a function of time but also dependent on phase-angle, we suppose the non-linear response of the vibro-impact system with time-varying mass is a function dependent not only on different time scale but also on the phase parameter. An approximate analytical solution of second order for the vibration is obtained by using Multi-Scales Method. The feasibility is verified by the numerical solution using Runge-Kutta algorithms. It is shown that the motion of the variable mass system has periodic behavior with the period of the changing mass, and the mass variation can only influence the system amplitude but not its cycle. However, the bigger the mass factor varies, the more intensive the response enlarges, and vice versa. The method and findings may be useful to analyze similar vibration systems with impact dampers or design the vibration control strategy.

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Based on the principle of Space Mechanism, the kinematics model of 6-DOF transportation vibration platform is described, and system kinematics analysis and calculation are finished. With an example, the displacement of actuator is solved according to the position and orientation of moving platform. The kinematics analysis is the basis of deciding system motion parameters, motion trajectory planning and system dynamics analysis.

The number of special purpose vehicle increase quickly recent year, so more Program Grounds were needed to performed the durability test. Now more than one Program Ground owned the qualification to perform the test. To secure the test results were uniform in different Program Grounds, a equivalence analysis method based on fatigue theory was given in the paper. The acceleration signals on vehicle were taken as the basic parameters in the method. At last, a high mobility vehicle was used to collecting the vibration signals on two different Program Grounds.The equivalence relationship was analyzed.

Installation is the key technology of the deepwater vertical collet connectors. Based on thorough analysis of the existing installation technology and construction resources, combined with the technical features of installation used to connect different types of jumpers, new designs of vertical collet connectors installation for rigid jumpers and flexible jumpers are proposed in detail in this paper.