A multi-finger robotic hand with an iris mechanism that we previously developed was driven by a single actuator and could grasp an object by wrapping fingers completely around its circumference at multiple points. However, the blades used to grasp objects were within the robotic hand mechanism, so it could only grasp objects small enough to fit within the hollow disk comprising the outer surface of the device body. Furthermore, the hand could not grasp objects smaller than the thickness of the hollow disk. The multi-fingered robotic hand proposed in this study has a new mechanism in which the blades of the iris are placed outside of the hand mechanism, and fingers shaped as equilateral triangular prisms extend perpendicular to the disk of the robotic hand body and are attached to the blade tip. Placing the blade outside the mechanism and adjusting the gear ratios within allows adjustments to the gripping torque and speed. The vertically extended fingers can thus grasp small objects and objects longer than the blade diameter. In this study, we performed geometric and theoretical analyses of the proposed multi-fingered robotic hand. We then fabricated an actual robotic hand, verified the validity of the analyses.

In recent years, rehabilitation has become increasingly important due to the aging of the population. Although many assistive devices have been developed, most of them are designed for gross movements of the upper and lower limbs in order to recover from diseases such as paralysis. However, complex and fine movements of fingers and arms, such as turning a knob to open a door or opening the lid of a plastic bottle, are also indispensable in daily life, and the deterioration of their movements leads to a decline in quality of life (QOL). In this research, we developed an integrated training system of fingers and upper limb for maintaining motor and cognitive functions of Elderly. The proposed system enables to train the gross motion and the fine motion simultaneously according to the instructions presented on the monitor display. And MR fluid-based variable damping devices give the user the changeable reaction force and feeling during the training tasks. In this paper, we will explain the designed structures and the control system of the proposed training system and show the results of the performance evaluation.

In this paper, we propose a method to remove distortion from highly-distorted input images by an ultra-wide-angle vision sensor. We extend an extensive look-up table step by step by taking into account reduction of chromatic aberration, as iteratively concatenating look-up tables for distortion removal using projective transformation of a local small square lattice pattern. Comparative evaluation experiments of RGB values before and after removing distortion were conducted. Results by our proposed method demonstrated effectiveness for more reliable feature point matching and object recognition by reducing chromatic aberration.

Thermal-based material identification has the advantage of distinguishing materials' thermal properties, which is one of the essential roles of recognizing contact objects. However, the thermal responses are sensitive to contact conditions, being affected not only by material properties but also by the initial temperature, contact surface, contact force, etc. The paper investigates the effect of contact force, time, and temperature differences on material classification by an assumption derived from a physical model and various kinds of experiments. The obtained knowledge might be useful for high-accuracy material classification based on thermal sensing.

In recent years, due to the decrease in the working population, restaurants and other food service industries are required to automate various tasks such as serving, washing, and storing dishes. In this paper, we propose a design method for a simple gripper with bent jaws that can be used to place multiple sizes and types of bowls upside down in a dishwasher rack. Then, we design and fabricate bent jaws suitable for grasping target bowls using the proposed method. Moreover, we confirm the effectiveness of the proposed method through experiments on the placement of the bowls.

This paper presents a novel control method of pneumatic soft actuators with arrayed chambers (PSAAC) for object manipulations. A discrete model composed of multiple linear elastic elements is introduced for representing the surface shape of PSAAC. Based the model, pressurization patterns of PSAAC for generating the desired surface shape under the contact pressure from the object is obtained using a mathematical optimization method. The proposed method is experimentally verified by the object tilting task and the object lifting task.

In recent years, jig-less assembly of variously shaped parts and development of versatile hands have been desired for variable type and variable volume production in the manufacturing industry. Focusing on shaft-shaped parts, we developed a versatile hand with parallel stick fingers that is equipped with functions for reorientation and alignment of those parts in our previous study. This paper describes the verification of feasibility and results of jig-less assembly of an example product (a gear unit) containing shaft-shaped parts with the hand.

This paper introduces a craft box assembly challenge conducted in a fourth-year undergraduate PBL (Project-based learning) class aimed at training robot SIers. Although robot competitions are held for various tasks, there are few beginner-level assembly challenges that focus on mechanical design. Therefore, we propose a challenge to build a robot system that automatically assembles a craft box using a desktop 4-axis robot arm. This paper presents the study of the assembly task, the contents of the class, and some of the systems created by the students.