Socially Acceptable Behaviour for Robots Approaching Humans using an Adaptable Personal Space Topics: Mobile, Wearable and Pervasive Devices; Models for Human-Agent Interaction; User Modeling and Profiling In Proceedings of the 12th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications - Volume 2: VISIGRAPP, 116-121, 2017 , Porto, Portugal