Tactile Feels in Grasping/Cutting Processes with Scissors

Abstract

Understanding the dynamic phenomena in grasping/cutting processes with scissors is important for the design of surgical robots and virtual reality systems. Here, we show the relationship between the mechanical stimuli and tactile sensations when forceps or scissors are used. Nineteen subjects grasped or cut objects and evaluated the tactile sensations in each of the processes. To conduct the tactile and mechanical evaluation simultaneously, subjects operated scissors that were fixed to a mechanical evaluation system. When subjects grasped urethane resin, stainless steel plate, and adhesive tape, soft, hard, and sticky feels were perceived, respectively. Dry, hard, and creaking feels were perceived in the paper cutting process. In addition, we observed four characteristic tangential force profiles in the processes. Regression analysis suggests the following findings: Hardness is perceived by the change of force and blade movement when the scissors make contact with the object. Stickiness is caused by the increase and decrease of force at the moment of peeling when the scissors break contact with the object. The cutting sensation is affected by fine force fluctuations during the scissors closing and the rapidly decreased force at the moment of cutting completion.