Initial interaction between a mobile robot and at least one user is described herein. 0 dtex and multifilament B yarns having a total fineness of not lower than 35 dtex,wherein the arrangements of the respective yarns in the warp and weft directions are such that the yarn constitution ratio \u201cB yarnA yarn\u201d is \xbc to 120 andwherein the A yarn-to-B yarn pitches are not longer than 7 mm. , referred to as a SmartStack module, that can be coupled directly to a device with a SmartStack module controller.