In this paper, a grip amplified glove consists of pneumatic artificial rubber muscles (PARMs) which are covered with an exoskeleton structure is developed. A bi-rticular mechanism with a PARM that is suitable for bending finger is realized. The glove has totally 10 DOFs consist of four units. To achieve power-assist motion properly, a PI control, which is based on the pressure value from the balloon sensor, is applied. Synchronized actuation of the PARMs adds to the user's own movements provides power and support the grasping. As the balloon type sensors are used, electric circuits can be separated from the finger parts that have advantage in the use of hostile environment. To evaluate the validity of the glove, the skin surface electromyography (EMG) signals of muscles are measured during grasping. These results demonstrate that the eff ectiveness of the power amplified glove.

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A rod-less type flexible pneumatic cylinder is a novel soft actuator. In this paper, a sliding and bending mechanism composed of these flexible pneumatic cylinders is described. Due to its simple structure and flexibility, the tested mechanism can generate a natural flowing movement with multi-motion such as bending, expanding and contracting. A master-slave attitude control method for the mechanism is proposed and tested. An analytical model of the mechanism is also proposed for the attitude control. In addition, an inexpensive quasi-servo valve using on/off control valves and a tiny embedded controller are utilized in the attitude control system to improve the control performance. As a result, the usability of the proposed mechanism and the effectiveness of the attitude control method by using the analytical model and the quasi-servo valve are confirmed. This mechanism will be applied to a rehabilitation device for a human wrist as our future work.

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This paper presents the first prototype of a pneumatically-driven forceps manipulator using a simple flexible joint for enhanced practicalities. A high performance spring component with wire actuation is employed for a two-degree of freedom (DOF) bending joint, and a two-DOF tendon drive system is implemented using four pneumatic cylinders. The kinematics is described using a continuum model and the dynamics are described as a linear elastic rod with the friction of wires. For the control system, a cascade controller with two control loops of the joint position and a pneumatic driving force is designed, which shows good performance at a sufficient working frequency for surgical operations. In addition, the forceps manipulator can estimate external forces using a disturbance observer. A link approximation model is introduced to design the observer for an intuitive approach. As the first step, the effectiveness of the force estimation is experimentally verified in the basic straight posture of the flexible joint.

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Robots have entered human life, and closer relationships are being formed between humans and robots. It is desirable that these robots be flexible and lightweight. For this reason, we studied and developed an artificial muscle actuator using straight-fiber-type artificial muscles derived from the McKibben-type muscles, which have excellent contraction rate and force characteristics. Therefore, we developed a 6-DOF artificial muscle manipulator, which has a wider moveable range than that using McKibben-type artificial muscle. However, this manipulator vibrates when receiving a sudden load, because the artificial muscle is flexible. For this problem, we suggest that control of joint stiffness is effective. In this paper, we controlled joint stiffness of the 6-DOF artificial muscle manipulator, and obtained a compliance ellipse of the end-effector. In addition, this manipulator controlled vibration of the end-effector by changing joint stiffness depending on the position of the end-effector.

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There are diseases of the small intestine such as Crohn’s disease or Polyp that cause Intussusception. These diseases were not discovered before using an conventional endoscope and the small intestine was called “The Dark Continent”. Recently, these diseases are inspected by a Double-Balloon Endoscope or Capsule Endoscope. However, the method used for these inspections have a few problems. Therefore, we proposed a new method of inspecting the small intestine. Utilizing our past research, we developed a robot for the small intestine using peristaltic crawling. The robot is attached to a conventional endoscope. When the endoscope reaches the small intestine, the robot is detached from the endoscope and moves forward and observes and treats the afflictions. In this paper, we fabricated the prototype and experimented in an acrylic pipe and elastic tube. In addition, we confirmed that the robot and endoscope can be separated in any place.

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In this study, we focus on a rehabilitation motion of human wrist joint and aim at supporting these rehabilitation training by introducing a mechanical system like a robot. A pneumatic parallel manipulator is introduced since it can drive enough D.O.F to correspond to a wrist motion and has inherent compliance characteristics resulted from air compressibility. We propose a new training method for a muscle strengthening training based on electromyography (EMG), where a pay-load is set between joint angle and the muscle we want to train directly. In addition, we propose a method to detect muscle fatigue based on a frequency analysis of EMG. The effectiveness of the proposed method is confirmed through some experiments.

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