In order to solve the problem of underwater robot contest URWPGSim2D robot simulation platform 1.0 release can not be the venue of the adaptive scaling and real-time collision detection is not easy to entities required to coordinate information and other issues, presents a simulation platform for space robotic fish with real-time dynamic entities rendering method. Designed the venue and the realization of dynamic physical rendering ideas, and design robot fish appearance and movement patterns according to the physical machine fish swimming simulation model, so that the site and to all the dynamic entity size of simulation platform can be according to the physical machine fish venue size scaling and display. At the same time, the new platform also provides a dynamic entity, a static entity, real-time location information for calls to other modules in the platform, and the need for collision detection to provide the coordinates of each edge of the data entity. Practice results show: the method can be physical machine fish game scene real-time, fidelity to appearances in URWPGSim2D simulation platform 2.