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We propose the planetary flywheel inerter, which is a new type of ball screw inerter. A planetary flywheel consists of several planetary gears mounted on a flywheel bracket. When the flywheel bracket is driven by a screw and rotating, each planetary gear meshing with an outer ring gear generates a compound motion composed of revolution and rotation. Theoretical analysis shows that the output force of the planetary flywheel inerter is proportional to the relative acceleration of one terminal of the inerter to the other. Optimizing the gear ratio of the planetary gears to the ring gear allows the planetary flywheel to be lighter than its traditional counterpart, without any loss on the inertance. According to the structure of the planetary flywheel inerter, nonlinear factors of the inerter are analyzed, and a nonlinear dynamical model of the inerter is established. Then the parameters in the model are identified and the accuracy of the model is validated by experiment. Theoretical analysis and experimental data show that the dynamical characteristics of a planetary flywheel inerter and those of a traditional flywheel inerter are basically the same. It is concluded that a planetary flywheel can completely replace a traditional flywheel, making the inerter lighter.

This paper proposes a new structure of hybrid cam-linkage mechanical press. First of all, the design process is introduced and positive movement simulation is done separately for hybrid cam-linkage mechanism and hybrid seven-bar mechanism in Pro/Mechanism. Through comparing the curves of slider’s output displacement, velocity and acceleration, it comes to the conclusion that the slider of hybrid cam-linkage mechanical press has better output motion characteristics. Then power and torque distribution of servo motor and general motor of the hybrid cam-linkage mechanical press is studied in ADAMS based on the simulation results. At last, torque of general motor and servo motor in practical work is analyzed by taking cold extrusion press as an example.

Though there has been a large number of studies concerning the modification of wood plastic composite materials, there is still more to be done. This report aims to study the effect of the coupling agents (PP-g-MAH, silane, titanate) and compatibilizer(SBS) on the mechanical properties of straw flour/waste plastic composites. Straw flour, waste plastic, modifying agents and other additives were mixed evenly in a high speed mixing machine. And the mixed materials were compounded into the pelllets using the twin-screw extruder. Then the test specimens were prepared by the injection molding. The influence of 4% coupling agent (PP-g-MAH, silane, titanate) on the mechanical properties of straw flour/waste plastic composites was researched, and the most suitable coupling agent to the composites was obtained. In order to increase the toughness of the composite materials and to furthermore improve the comprehensive mechanical properties, the WPCs with different contents styrene butadiene styrene (SBS) were investigated. The experimental results showed that the coupling agent PP-g-MAH and the content was 4%, the mechanical properties of the composite materials were better; when SBS content was 5%, the maximum increases of tensile strength, flexural strength and impact strength of SBS modified WPCs were by 14.34%, 20.75%, 34.38% compared to those of neat WPCs respectively.