Interdisciplinary System Simulation of a Tracked Compost Turner

The investigation “autonomous navigation for tracked compost turners” (ANTON) aims to automate composting machines by means of satellite-based navigation technologies. In the course of this project, a navigation module and a control module for a driverless, electrically driven, tracked compost turner will be developed and tested. A fundamental task during the process of composting is turning the biogenic material with machines. Currently, this is conducted and monitored by an operator inside the driver’s cab of a diesel-driven compost turner or conventional loader. Due to low driving speeds of compost turners (approx. 50 to 300 m/h), high ambient temperatures, released gases, and bad smell during compost turning, the operator is exposed to very unpleasant conditions. Further on, the currently used diesel engines do not meet the expectations of the customers regarding sustainability and green technologies which is the reason why the focus is on electric powered system. The primary innovation is determining a precise and robust position of a slowly moving vehicle like the compost turner under the so far non-tested surrounding conditions. For the vehicle’s motion control, a control structure shall be established and evaluated with the help of the method “Software in the Loop” (SiL). For that matter, the controller software is directly coupled with a multibody simulation model, which describes the driving characteristics of the tracked vehicle. The main goal of the investigation is to develop a prototype of a compost turner which can fulfill the required task “turning windrows” autonomous. Further on the developers expect a minimum of initial start-up time because a significant number of crucial tests for the controller are already done within the SiL system. This approach will decrease the cost of the investigation significantly. Within this article, the authors will mainly elaborate on the interdisciplinary system simulation and its coupling using functional mock-up interfaces, which outlines the base ot SiL method. The system simulation will cover the coupling of a signal flow-oriented simulation to simulate the control structure, a multibody simulation, which simulates the mechanics of the compost turner’s tracks and a discrete element method (DEM) simulation, which simulates the force feedback of the turning of the biogenic material.