In order to solve the requirements of navigation robot for universality and compatibility, this study designs a navigation robot experiment platform accord to the concept of modular design, which consists of a microprocessor module, motor module, communication module, sensing module, and power module. Meanwhile, aiming at the cumulative error problem of the navigation robot in the construction of an environment map, a maximum expected probability mapping algorithm, which combines prior estimation and maximum likelihood estimation, is proposed to solve the cumulative error. Finally, the navigation robot platform is used to carry out the experiment of mapping and autonomous navigation. The coordinates obtained by the indoor motion capture system are used as a reference to validate the algorithm, which can effectively reduce the cumulative error generated by the robot.