Papers by Author: L.H. Zhu

Abstract: On the basis of analyzing assembly process of main structural components in CA6140 lathe, 3D models for those components were established with CAD software UGNX6.0. Virtual assembly and motion simulation of the structure parts were performed with virtual technology. A set of virtual assembly system of CA6140 engine lathe was developed with programming software Visual Basic 6.0. It contains six main modules about spindle box, feed box, apron, tailstock, turret, etc. Dynamic simulation and motion simulation of the corresponding components in entity lathe can be realized, respectively. And also, mechanical structure, working principle, assembly relation between different components and motion transmission process of the lathe can be realistically reproduced with the system. This virtual assembly system not only can be used to analyze and transform old products, but also can be used in new products development, and to some extent, can be used to replace the prototype. It is an indispensable tool in the employee training and mechanical engineering activities.

Abstract: By researching on the main factors affecting the active zone area strain of electroactive dielectric elastomers, the suitable conditions of area strain for the material in the application as artificial muscles actuator was determined. In the experiments, the strain characteristics of the material was investigated under uniaxial pre-stretching, uniform biaxial pre-stretching and non-uniform biaxial pre-stretching respectively. In addition, the strain rates of the materials active zone under different ratio of the active zone to the window radius of the materials were investigated. The experimental results show that the area strain of active zone would have inflexion under any pre-stretching condition, and the area strain increased with applied voltage increasing, decreased with the ratio of the active zone to the window radius increasing. It could be found that the strain conditions have an important influence on the area strain of the active zone.

Abstract: Prestrain affects the performance of dielectric elastomer actuators so much that rare actuators is used before pre-stretching. In this article, the author made a series of circular actuators with acrylic VHB4910 and graphite mixture electrodes, and performed contrast experiments, under non-prestrain, uniaxial prestrain and equibiaxial prestrain, respectively, to figure out the changing of area strain against prestrain. Result of experiment indicates that the film actuator obtains the highest output strain while applying equibiaxial prestrain. An optimum prestrain ratio of actuators, in this research, occurs between 150%~200% under equibiaxial prestrain condition. This result has practical value in the future design and use of dielectric elastomer actuators.