This paper describes the application of a 3D-simulation model to develop the control system of a demolition excavator. In order to simplify the system development and provide means for early prototype validation, a simulation-based development workflow is presented. A 3D model of the excavator, a demolishable wall, a virtual LiDAR sensor as well as CAN and Ethernet communication interfaces are used to support the development and testing of different software components as well as a test setup for automation strategies.