To improve passing topography capacity of 2WD truck on soft soil, A track device circling driving wheel (TDCDW) is developed and tested. Tests are conducted on sandy loam to determine the traction performance of the TDCDW. The drawbar pull and the slip of the 2WD truck with TDCDW are measured by the dynamometer vehicle. The soil resistance of 2WD truck with TDCDW is got by pulling the wire rope fixed on truck with the winch and reading the load cell fixed on the wire rope. The main results of this study are: The load on the front wheel has no influences on the tractive effort of TDCDW on sandy loam. The slip of the vehicles with the TDCDW is not the simple assembled slip of wheel on TDCDW and TDCDW on sandy loam. When the load is the same, the maximum tractive effort of truck with TDCDW is equal to the maximum tractive effort of tracked vehicle with the same contact area on sandy loam.

The stress distribution of an S-shaped micro spring fabricated by the micro-electro-mechanical-system (MEMS) technology was analyzed by the finite-element method (FEM) using ANSYS software, which showed that the stress concentration is located in the inner corner of the turning round. To reduce the maximum stress but not change the spring coefficient, an optimization S-shaped micro spring with the slope cross section was designed. The width of one end of the turning round is increased from the original 80μm to 100μm, while the other is decreased from 80μm to 21.5μm. The spring coefficient formula of the optimization S-shaped micro spring was calculated out by the Castigliano second law, and the difference between the formula and the FEM is 2.7%. At the same time the FEM simulation shows that the maximum stress of the optimization S-shaped micro spring can be reduced by 32.7% while the spring coefficient is the same comparing with the primary S-shaped micro spring, which shows that the mechanical performance of the optimization S-shaped micro spring is better than that of the primary S-shaped micro spring.

The self-loading device used for side-crane is put forward. Its structure is presented. Based on the force analysis when the side-crane works at flat ground, the mathematical model is established when the crane working at uneven ground. And the design calculation is performed. The self-loading device’s optimal design is accomplished. Based on the above calculation results, the self-loading prototype is manufactured. And the design method can be adopted to the similar equipment’s structural design.

A VCA direct-drive 2-DOF precision positioning table is put forward, which can be applied to IC packaging for wafer wire bonding equipment. With the help of a novel elastic decoupling mechanism, the VCA is mounted on the baseboard, diminishing its moving inertia, improving its dynamic performance. The table structural is detailed and its dynamic design approach is proposed. The prototype experiment shows that the new 2-DOF positioning table is of higher speed and higher accuracy than the traditional ones.

As the important content of modern design method, virtual design plays a key role in machine system optimal design. The VDT (Virtual Design Technology) is discussed in detail. The flow of virtual design is given. Based on the flow of virtual design, the application of virtual design to container loading device is studied.