This video shows the basic functions of HFAMRO-2 equipped with the step-on interface (SOI). In the SOI the projected screen is used as a bilateral interface. It not only presents information from the equipment to the user but also delivers the instructions from the user to the equipment. HFAMRO is intended to represent the concept based on which robots interact with users. It assumes, for example, the ability to play 'tag' - in this case, playing tag with light, similar to 'shadow' tag. The HFAMRO-2 mobile robot, developed to study the SOI's application with mobility, has two sets of the SOI consisting of a projector and a range scanner on a mobile platform. The projector displays a direction screen on a travel surface and the two-dimensional range scanner detects and measures the user's stepping to specify the selected button.