<p>Our study investigates how different mapping strategies of distance information affect performance in an object exploration task with a teleoperated virtual robot. The task was to find an object inside a backpack using a simulated robotic gripper. A virtual proximity sensor tracked the distance between the tip of the gripper and the object. The distance was conveyed as a vibration pattern on the users index finger. This is the only information that was received to guide the user towards the object. The goal was to locate the hidden object by moving the tip of the gripper as quickly and as closely towards the object as possible without touching it. We implemented three different mapping strategies that utilized continuous frequency and amplitude variations of sinusoidal vibrations to encode distance. The present study provides empirical evidence that the mapping strategy can affect accuracy when approaching an object. We found that linear feedback sensations help to sense the rate of approach. Non- linear feedback perception can provide cues that enable more accurate approximation of the absolute distance. We found that experienced participants could selectively attend to and integrate frequency and intensity cues when both modalities are changed simultaneously. Inexperienced participants were not able to make this distinction and found it difficult to interpret such a signal. They preferred one-dimensional changes.</p>

The touch of textile products is a complex process, depending on the interaction between the human finger and the textile product. The evaluation of the touch, or so named handle properties is complex process, requiring samples, testing humans or special testing devices. The numerical evaluation of the surface is until now not reported, because of the complexity of the textile products. This work presents the current state of the 3D modelling of textile products at yarn and fiber level and the required additional steps in order these models to get applicable for numerical simulation of the fabric touch. This work cover only the aspects related to the textile representation and do not include the modelling of the human finger as mechanical and receptor system during the interaction. / Die Berührung und der Griffevaluation von Textilprodukten sind komplexe Prozesse, die von der Interaktion zwischen dem menschlichen Finger und dem Textilprodukt abhängig sind. Die Bewertung der 'Touch'- oder so genannten Griffeigenschaften ist ein komplexer Prozess, der Proben, Testpersonen oder spezielle Testgeräte erfordert. Die numerische Simulation der Oberflächenbeschaffenheiten ist aufgrund der Komplexität der textilen Produkte bisher nicht bekannt. Diese Arbeit stellt den aktuellen Stand der 3D-Modellierung von Textilprodukten auf Garn- und Faserebene und die erforderlichen zusätzlichen Schritte vor, damit diese Modelle für die numerische Simulation der Haptik von Textilien eingesetzt werden können. Es werden nur die Aspekte abgedeckt, die sich auf die Darstellung der Textilien beziehen und beinhaltet nicht die Modellierung des menschlichen Fingers als mechanisches und rezeptives System während der Interaktion.