This paper describes precision enhancement of an optical three-axis tactile sensor capable of detecting both normal force and tangential force. The sensor’s single cell consists of a columnar feeler and 2-by-2 conical feelers. We have derived equations to precisely estimate the three-axis force from the area-sum and area-difference of the conical feelers’ contact areas by taking into account wr...

With the advent of the aging society, the demand for nursing care for the elderly is becoming much larger. The application of robotics to helping on-site caregivers is consequently one of the most important new areas of robotics research. Such humaninteractive robots, which share humans’ environments and interact with them, should be covered with soft areal tactile sensors for safety, communica...

Sensors provide robotic systems with the information required to perceive the changes that happen in unstructured environments and modify their actions accordingly. The robotic controllers which process and analyze this sensory information are usually based on three types of sensors (visual, force/torque and tactile) which identify the most widespread robotic control strategies: visual servoing...

BACKGROUND Because gastrointestinal cancers are generally firm, the presence and extent of a tumor can be assessed by touch during surgery. However, an objective scale for evaluating tissue hardness does not exist. We developed a new instrument, the endoscopic ultrasonic tactile sensor, that allows objective evaluation of hardness. In this study the usefulness of this device for diagnosis of th...

This chapter provides an overview of force and tac-tile sensing, with the primary emphasis placed on tactile sensing. We begin by presenting some basic considerations in choosing a tactile sensor and then review of a wide variety of sensor types, including proximity, kine-matic, force, dynamic, contact, skin deflection, thermal and pressure sensors. We also review various transduc-tion methods,...

Active touch with voluntary movement on the surface of an object is important for human to obtain the local and detailed features on it. In addition, the active touch is considered to enhance the human spatial resolution. In order to improve dexterity performance of multifinger robotic hands, it is necessary to study an active touch method for robotic hands. In this paper, first, we define four...

A novel capacitive tactile sensor using a polyurethane thin film is proposed in this paper. In previous studies, capacitive tactile sensors generally had an air gap between two electrodes in order to enhance the sensitivity. In this study, there is only polyurethane thin film and no air gap between the electrodes. The sensitivity of this sensor is higher than the previous capacitive tactile sen...

We propose an experience-based approach to the problem of blind grasping, stable robotic grasping using tactile sensing and hand kinematic feedback. We first collect a set of stable grasps to build a tactile experience database which contains tactile contacts for each stable grasp. Using the tactile experience database, we propose an algorithm to synthesize local hand adjustment that controls t...

This paper proposes a learning model that enables a robot to acquire a body image for parts of its body that are invisible to itself. The model associates spatial perception based on motor experience and motor image with perception based on the activations of touch sensors and tactile image, both of which are supported by visual information. The tactile image can be acquired with the help of th...