34 accepted papers
The McKibben muscle, widely employed in antagonistic drive robots, exhibits approximately 20% contraction under pneumatic pressure but lacks crucial passive extensibility. Previous attempts to achieve passive extensibility resulted in reduced overall contraction ratios due to the series connection o
The McKibben muscle can produce a high force-to-mass ratio, beneficial for various applications in the soft mechatronics field. The thin McKibben muscle, which has a small diameter, has the advantage of a high force-to-mass ratio and sufficient flexibility for use in a bent state. This flexibility p
Hydraulic artificial muscles offer superior performance compared to most pneumatic artificial muscles, but their suitability in multi-DOF robotics remains unverified. We fabricated a 7-DOF power soft robot spanning over 1.5 m using 29 McKibben hydraulic artificial muscles. We analyzed the proposed r
Soft robotics, including soft grippers and manipulators, are increasingly required to function more adaptively and securely in unknown environments. However, conventional soft pneumatic grippers often grasp and hold objects via the active bending of multiple fingers, making it challenging to grip an
Synthetic fiber ropes are widely used for robots because of their advantages such as lightweight, high tensile strength and flexibility. However, there is limited information on the physical properties of synthetic fiber ropes when used for robots. This study focuses on repetitive twisting of synthe…
The neck of a giraffe has excellent characteristics that can serve as a good alternative for designing a large robotic mechanism. For example, the neck can rapidly move when performing necking, a motion where the giraffes strike each other’s necks. Furthermore, the neck of a giraffe helps prevent im
The primary role of a robot exploring an unknown space is to investigate the state and the spatial shape of the environment. We have designed a soft robot that aims to move forward in an unknown space as it recognizes and adapts to the spatial shape of the environment. We previously reported that so
This letter proposes a novel method to accomplish shape recognition by utilizing a tensegrity structure with a soft sensor via a recurrent neural network (RNN). The combination of soft tensegrity and soft sensors make it capable of recognizing the deformation to reflect the shape of its surroundings
The exploration and inspection of narrow spaces in industrial plants require the use of long-reach redundant manipulators with large three-dimensional (3D) workspaces. To this end, in a previous work, a coupled tendon-driven articulated manipulator with a total length of 10 m and yaw joints for 3D m
A hydraulic drive system can generate a large force and is impact resistant. Thus, robots that utilize hydraulic drive systems have been developed for use in disaster areas. In a hydraulic drive system, it is necessary to design the motion of the robot within the capacity of the pump unit, but it is…
Robotic manipulators using thrusters for weight compensation are an active research topic due to their potential to exceed the limits of maximum length. However, existing manipulators that use thrusters have limitations of maximum length because the hardware design is not sufficiently refined. This
This letter proposes a particular tensegrity topology for a humanoid hand in which the motion of the hand is actuated using thin McKibben artificial muscles. The specific actuation pattern for this tensegrity hand with multiple degrees of freedom, which includes the location of the artificial muscle
Pneumatic pressure is a widely used power source in soft actuators as it has advantages such as simplicity of design, structure, and driving principle. However, electromagnetic valves are used for controlling pneumatic pressure, and these tend to be large and heavy, thus reducing flexibility in the
Robots currently have a wide range of practical applications. However, their widespread use is limited by long design and manufacturing times as well as increasingly complex drive system electronics and software, which have led to high development costs. Therefore, simpler manufacturing, driving, an
Ionic polymer-metal composites (IPMC) actuators are popular because they can be driven at a low voltage, possess excellent responsiveness, and can perform soft motions similar to that of living creatures. Conventional IPMC soft robots are manufactured by cutting and assembling IPMC sheets. However,…
This letter proposes a new wire-driven mechanism in order to relay many ropes very simply and compactly. Ropes pass through in a joint while bundled. Synthetic fiber rope can slide and twist, exploiting its low friction coefficient. In order to use this mechanism, it is necessary to investigate the
In this letter, we propose a novel active weave named “18 Weave” using a thin McKibben muscle and report on the application to a prototype soft power support suit for the upper limb. The active weave utilizes the flexibility of the thin McKibben muscle, which is used for warps and wefts. From the pr
In this letter, we report on a multi-layer casting process of an ionic polymer metal composite actuator to produce a monolithic thin film robot (MTFR). This robot is developed on the basis of the novel concept of a soft robot, which consists of a body united with actuators and does not require mecha
Among the various pneumatic actuators, thin McKibben muscles are particularly attractive owing to their high performance in terms of high contraction ratio, high flexibility, and productivity. One of the challenges for thin McKibben muscles and other pneumatic actuators is the fact that they general…
The decommissioning of the Fukushima Daiichi Nuclear Power Plants is a national urgent problem in Japan. The distribution and characteristics of the fuel debris inside the nuclear reactor must be investigated to safely retrieve them. This letter describes a 10-m-long articulated manipulator for inve
This letter presents a novel concept of braiding thin McKibben muscles to improve their contracting ability compared to original muscles. Whereas a single original muscle and the conventional bundled muscle had a contracting ratio of 28%, braiding the muscles realized a contracting ratio of 37%. We
A synthetic fiber rope is potentially capable of replacing a stainless steel wire rope because it is light weight, and has high tensile strength and flexibility. In order to exploit the maximum tensile strength of the rope, a terminal fixation method with a sufficient fixing force is essential. Howe
A synthetic fiber rope, which is lightweight and has a high tensile strength and flexibility, is receiving considerable attention as a replacement for a stainless steel wire rope. This letter describes its ability to endure repetitive bending. We performed experiments in conformity with the ISO 2020
This letter introduces a lightweight hexapod robot, Giacometti robot, made with long and narrow legs following the Alberto Giacometti's sculpture conception. The goal is achieved by, first, using multiple links with thin and soft McKibben actuators, and second, choosing a leg design which is narrow
In recent years, synthetic fiber ropes have attracted much attention because of their potential to increase the load capacity, reduce the size, and lighten the weight of tendon-driven mechanisms. However, the mechanical characteristics of synthetic fiber ropes in a dynamic loading situation remain a
As part of our research on developing different types of Giacometti robots, the potential of a very long, very light, and very simple robot arm with a balloon body is discussed in this paper. Although this robot arm is not suitable for precise positioning, rapid motion, and high load capacity, which
As a part of our research on several different types of Giacometti robots, a 20-m-long, considerably light, and simple robot arm, referred to as the Giacometti arm, is developed in this study. Even though the Giacometti arm is not suitable for precise positioning, rapid motion, and high load capacit…
Unmanned rescue, observation and/or research vehicles with high terrain adaptability, high speed, and high reliability are needed to reach difficult locations. However, most vehicles achieve improved performance over rough terrain at the expense of low speed and/or complex mechanisms. We developed a…
In recent years, industrial robots have been applied to food production because of its huge potential market. Although cooking large amount of foods are done by specially designed cooking machines, dishing up the cooked foods remains as a labor-intensive task. To solve this problem, this paper propo
The crank wheel mechanism, consisting of a wheel mechanism and parallel links connected to each wheel, achieved high mobility and efficiency because it has both wheels and legs in a simple structure. However, each prior model of crank wheel mechanism has had shortcomings such as mass oscillation or…
An amphibious all terrain mobile robot is required for disaster response tasks. In this paper, we propose “R-Crank”, which has a simple four wheels driving configuration with crank links, connecting to ipsilateral front and rear wheels so as to form parallel four-bar linkage systems. The crank links…
In this paper, a lightweight master interface for a surgical robot system is proposed. The position of the human hand is measured by a non-contact motion tracker, but the force feedback is realized by a handheld haptic device. A gripping force is displayed by a pneumatic bellows, which is smaller an…
Development of intuitive user interface of a dexterous forceps with wrist joint for minimally-invasive surgery (MIS) is important for reducing the surgeon's confusion and fatigue. In this paper, a wearable robotic forceps manipulator is proposed. By measuring the wrist attitude of the surgeon by a m…
Generally, wheel mechanisms are inferior to a tracked or walking mechanism in terms of step climbability or traversability in rough terrain; however, they are superior in terms of energy efficiency, structural simplicity, and carrying capacity. This paper proposes a new wheel mechanism, the swing-gr…