This paper describes a collaborative modelling exercise using the DESTECS framework. The DESTECS approach allows engineers and software designers to collaborate to produce system models that contain a discrete-event (DE) model of a controller and continuous-time (CT) model of a plant. We call these models co-models and call their execution co-simulation. The DESTECS tool couples existing DE and CT tools (Overture and 20-sim, respectively) allowing engineers to use paradigms and tools with which they are familiar, while collaborating to construct these shared system models. The work involved collaborative modelling of a line-following robot. We report on both the details of the models and experience in producing them.