中文摘要：

机械-液压约束活塞发动机（MHCPE）主运动系统优化设计是提高MHCPE性能的关键，优化涉及多个学科，需自行开发多学科协同优化平台以实现结构优化。介绍了MHCPE优化设计平台的结构组成和使用方法，建立了主运动系统的协同优化模型并进行了优化分析。结果显示，优化过程收敛速度快，主运动系统的体积减少大约12．62％，其中连杆体积增大9．26％，曲轴减小14．06％。该模型可为解决更为复杂的MHCPE优化问题打下基础。

英文摘要：

Mechanical-hydraulic Confined Piston Engine （MHCPE） main motor system optimization is the key to improving MHCPE performance, whose optimization involves multiple disciplines. It needs to develop its own optimized platform for multidisciplinary collaboration in order to achieve structural optimization. It introduces the structure and uses of the MHCPE optimized platform, and establishes its optimization model for the optimization analysis. The results show optimization process converges faster than usual, and the volume of primary motor system reduces about 12.62; and with link increased 9.26% and crankshaft reduced 14.06%. It is the foundation to solve more complex problem of MHCPE optimization.