Production cells are typically built up of many heterogeneous components which are controlled by a central unit such as a standard programmable logic controller. Engineering of such cell controllers is usually based on an imperative programming paradigm. All possible decision situations are defined manually and coded offline, which is an acceptable method for simple or fixed recurring automation tasks. Implementing complex control and adaptation strategies however leads to disproportionately high engineering efforts, which incur whenever process changes are required. This paper presents a modelbased assembly control concept and a cell control engineering methodology. The concept was validated using a micro-slab laser assembly process within a multi-robot assembly cell.