Two finger grasping simulation with cutaneous and kinesthetic force feedback Claudio Pacchierotti 1,2 , Francesco Chinello 1 , Monica Malvezzi 1 , Leonardo Meli 1 , and Domenico Prattichizzo 1,2 1 Department of Information Engineering, University of Siena, Via Roma 56, 53100 Siena, Italy 2 Department of Advanced Robotics, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy {pacchierotti,chinello,malvezzi,meli,prattichizzo}@dii.unisi.it Abstract. This paper presents an experiment of two finger grasping. The task considered is the peg-in-hole and the simulated force feedback is cutaneous or kinesthetic. The kinesthetic feedback is provided by a commercial haptic device while the cutaneous one is provided by a new haptic display proposed in this work, which allows to render at the fingertip a wide range of contact forces. The device consists of a mobile surface, which interacts with the fingertip, actuated by three wires directly connected to the motors placed on the grounded struc- ture of the display. This work summarizes the design of the proposed display and presents the main relationships which describe its kinematics and dynamics. Results showed that cutaneous feedback exhibits improved performances when compared to visual feedback only. 1 Introduction Cutaneous feedback is important to simulate interactions with objects in a virtual envi- ronment. Single-contact haptic devices, such as the Omega devices (Force Dimension, CH), provide haptic feedback, consisting of both cutaneous and kinesthetic forces, to the user, making him/her aware of the relative position of neighboring parts of the body by means of sensory organs in muscles and joints [1]. Watanabe et al., in [2], devel- oped a system for controlling cutaneous sensations of surface roughness by applying ultrasonic vibration to the surface. In [3] the authors proposed an approach to provide human cutaneous sensation using surface acoustic wave. A pulse-modulated driving voltage excited temporal distribution of shear force on the surface acoustic wave sub- strate. The force-friction distribution was perceived as cutaneous sensations at receptors in the skin. A widely-used approach for providing cutaneous sensations is employing dynamic pin-matrices. Ikei et al., in [4], developed a cutaneous display which has 50 vibrating pins. The vibratory pin array included 5x10 contact piano-wires 0.5mm in diameter, aligned in a 2mm pitch with a vibration frequency of 250Hz. In [5] the authors devel- oped a pin-array cutaneous display, composed of a 6x5 pin-array actuated by 30 piezo- electric bimorphs. It was able to display planar distributed and Braille cell patterns. Pin-arrays were also employed in [6], where the authors used a solenoid, a permanent