The increased diffusion of cooperation between humans and robotics in manufacturing systems is one of the next things to implement within robotics. Since the computer power gets more and more powerful, the possibilities increase to achieve safer working environment, due to that all safety signals demands fast management of data. This could lead to a possibility to work closer and more direct with a robot, using the robot as a third hand. Within an EU FW7 funded project called LOCOMACHs (Low Cost Manufacturing and Assembly of Composite and Hybrid Structures) there are one study focusing on how to support a future higher TRL-leveled HMI cell (Human Machine Interaction) in an assembly task. The main objective in this paper is to present how different external safety systems could support the whole HMI assembly cell to work properly in an industrial context. The scenario for HMI, in this case, is that an operator enters into the robot working area with the aim to perform an assembly task that need two hands. There are different support systems that could be applied to this assembly application, but every one of these needs to coincide with official standards to be applied in an approved industrial HMI assembly cell. The different safety support systems that are used in this research are light barriers, physical barriers and three-position enabler. These safety support systems are tested in a demonstrator assembly cell using a mock-up wing part. The tests with the selected safety support systems in the physical demonstrator will be compared with a concept that uses cameras to achieve the same degree of safety.