Acta Medica Okayama 0924-4247 184 2012 An ultrasonic motor for cryogenic temperature using bolt-clamped Langevin-type transducer 134 140 EN Daisuke Yamaguchi Takefumi Kanda Koichi Suzumori In this study, a small ultrasonic motor driven under cryogenic temperature conditions has been fabricated and evaluated. Since transducer performance generally decreases at cryogenic temperatures, we designed and fabricated a bolt-clamped Langevin-type transducer for operation at cryogenic temperature. We simulated the influence of thermal stress on the transducer. The results from simulation were used to design the transducer, and it was then used to fabricate an ultrasonic motor for cryogenic temperature. The maximum diameter and the height of the motor are 30 mm and 38.7 mm. To enable the motor to be driven at cryogenic temperature, we evaluated the relationship between the contact pre-load and the lowest rotatable temperature. The motor's driving performance was evaluated at both room temperature and cryogenic temperatures. In a 4.5 K helium gas ambient, the rotation speed and starting torque were 133 rpm and 0.03 mu N m when the applied voltage was 50 Vp-p. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 0924-4247 164 1-2 2010 Multiplex pneumatic control method for multi-drive system 88 94 EN Yasutaka Nishioka Koichi Suzumori Takefumi Kanda Shuichi Wakimoto Pneumatic actuators have several advantages such as light weight safety low cost and high compliance However many pneumatic actuators have complicated systems that include a compressor air tubes and pneumatic valves with electrical wires This research proposes a new control method for a multiplex pneumatic transmission constructed with special resonant valves and air tubes with a control system driven by air vibration in air tubes without electrical wires The control is simplified and effective for pneumatic systems having many degrees of freedom In this paper the development of a primitive model of the resonant valve and a prototype valve is described In addition two control methods which are a superimposing method and a time-sharing method are shown and the independent driving of four actuators is realized by using one of the control methods with air tubes only. No potential conflict of interest relevant to this article was reported.

IOP Publishing Acta Medica Okayama 0964-1726 20 10 2011 Design of a variable-stiffness robotic hand using pneumatic soft rubber actuators EN Jun-ya Nagase Shuichi Wakimoto Toshiyuki Satoh Norihiko Saga Koichi Suzumori In recent years, Japanese society has been ageing, engendering a labor shortage of young workers. Robots are therefore expected to be useful in performing tasks such as day-to-day support for elderly people. In particular, robots that are intended for use in the field of medical care and welfare are expected to be safe when operating in a human environment because they often come into contact with people. Furthermore, robots must perform various tasks such as regrasping, grasping of soft objects, and tasks using frictional force. Given these demands and circumstances, a tendon-driven robot hand with a stiffness changing finger has been developed. The finger surface stiffness can be altered by adjusting the input pressure depending on the task. Additionally, the coefficient of static friction can be altered by changing the surface stiffness merely by adjusting the input air pressure. This report describes the basic structure, driving mechanism, and basic properties of the proposed robot hand. No potential conflict of interest relevant to this article was reported.

日本設計工学会 Acta Medica Okayama 0919-2948 46 9 2011 空気圧剛性可変フィンガを有するバルーン型腱駆動ロボットハンドの開発 517 523 EN Jun-ya Nagase Shuichi Wakimoto Norihiko Saga Koichi Suzumori No potential conflict of interest relevant to this article was reported.

日本ロボット学会 Acta Medica Okayama 0289-1824 29 7 2011 大腸内視鏡挿入支援を目指したラバーチューブアクチュエータの設計と基礎駆動特性 619 625 EN Shuichi Wakimoto Ken Ozaki Koichi Suzumori Colonoscopy is an important medical action to detect disorders like colon cancer. However generally it is difficult to insert a scope into the colon, because the colon is flexible and complex shape. This study aims at development of an actuator which can add propelling ability to a colonoscope. We focus on rubber pneumatic actuators, because advantages of them, for example, high compliance, low cost, water proof, and so on, agree with the required properties of medical devices. In this paper, we design a novel rubber actuator consisting of three air chambers by nonlinear FEM (finite element method) and fabricate the actuator employing the design by extrusion molding method. Basic characteristics of the actuator are clarified by a motion capture system, and functional motion leading assisting colonoscope insertion is observed. Actually using dummy endoscope, transportation ability by the actuators is confirmed experimentally and insertion experiments into a large intestine phantom are conducted. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 0169-1864 25 9-10 2011 Miniature Pneumatic Curling Rubber Actuator Generating Bidirectional Motion with One Air-Supply Tube 1311 1330 EN Shuichi Wakimoto Koichi Suzumori Keiko Ogura Soft actuators driven by pneumatic pressure are promising actuators for mechanical systems in medical, biological, agriculture, welfare fields and so on, because they can ensure high safety for fragile objects from their low mechanical impedance. In this study, a new rubber pneumatic actuator made from silicone rubber was developed. Composed of one chamber and one air-supply tube, it can generate curling motion in two directions by using positive and negative pneumatic pressure. The rubber actuator, for generating bidirectional motion, was designed to achieve an efficient shape by nonlinear finite element method analysis, and was fabricated by a molding and rubber bonding process using excimer light. The fabricated actuator was able to generate curling motion in two directions successfully. The displacement and force characteristics of the actuator were measured by using a motion capture system and a load cell. As an example application of the actuator, a robotic soft hand with three actuators was constructed and its effectiveness was confirmed by experiments. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 0169-1864 24 10 2010 Development of an Intelligent Chair Tool System Applying New Intelligent Pneumatic Actuators 1503 1528 EN Ahmad 'Athif Mohd Faudzi Koichi Suzumori Shuichi Wakimoto This paper develops an Intelligent Chair Tool (ICT) - a new chair-type human and machine interaction seating system powered by 36 intelligent pneumatic actuators. This tool can be used to facilitate investigation of chair shapes from spring and damping effects of seating and backrest surfaces. Each actuator used consists of five extensive elements of encoder, laser strip rod, pressure sensor, valves and PSoC microcontroller incorporated in a single device. By using the ICT, different shapes, spring and damping characteristics can be obtained to aid the design of chairs from the control inputs, i.e., position x, stiffness k(s) and viscous coefficient c. Several control algorithms are presented to realize the communication and control system, and to obtain all data in real-time. The control methodology presented contains an inner force loop and an outer position loop implemented using a unified control system. The specification, development design and experimental evaluation of the ICT control system and actuator used are presented and discussed. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 127 1 2006 A micro ultrasonic motor using a micro-machined cylindrical bulk PZT transducer 131 138 EN Takefumi Kanda Akira Makino Tomohisa Ono Koichi Suzumori Takeshi Morita Minoru Kuribayashi Kurosawa In this paper, a micro ultrasonic motor using a micro-machined bulk piezoelectric transducer is introduced. The cylindrical shaped bulk piezoelectric transducer, a diameter of 0.8 mm and a height of 2.2 mm, was developed as stator transducer for traveling wave type ultrasonic motor. The transducer was made of lead zirconate titanate (PZT) bulk ceramics, and formed by micro machining, Ni plating and laser beam cutting process. Using this stator transducer, we have fabricated a cylindrical micro ultrasonic motor, a diameter of 2.0 mm and a height of 5.9 mm. We have also evaluated some characteristics and succeeded in driving the micro ultrasonic motor. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2004 Nutation motor : a new direct-drive stepping motor for robots 21 22 EN Koichi Suzumori Takefumi Kanda Kazuo Uzuka Isao Enomoto A new type of stepping motor, named nutation motor was developed. This motor has a reduction mechanism consisting of a pair of bevel gears, realizing high torque and high resolution stepping motion. Three prototypes, two pneumatic nutation motors and an electric nutation motor, were designed, developed, and tested. We show the basic driving principle and the experimental results in this paper. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2004 New actuators and their applications: from nano actuators to mega actuators 15 21 EN Koichi Suzumori The present report describes R&D activities on new actuators undertaken at our laboratory at Okayama University for the past three years. These activities include various types of actuators, such as electromagnetic, electrostatic, piezoelectric, pneumatic, and hydraulic actuators, ranging in size and force from the nano to the mega range. These actuators are described in four categories: microactuators, power, intelligence, and novel principle. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 2002 Pneumatic direct-drive stepping motor for robots 2031 2036 EN Koichi Suzumori Tatsuya Hashimoto Kazuo Uzuka Isao Enomoto A new type of pneumatic stepping motor, named pneumatic nutation motor, was developed. This motor achieves stepping positioning of 720 steps/rotation without any electrical devices or sensors mounted on the servo mechanisms. This makes the motor possible to be used under hazardous conditions such as in water and in strong magnetic fields where conventional electromagnetic motors cannot be used. The motor torque is so big that the motor can be used as a direct motor. In this report, the driving principle and design of this motor are presented. Its characteristics are analyzed experimentally and theoretically. The motors were applied to a parallel linkage mechanism with six degrees of freedom. The mechanism shows that the pneumatic nutation motors can be used as a direct servo motor for robot mechanisms. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 4 2004 Active link mechanisms for physical man-machine interaction 3895 3900 EN Jumpei Ochi Tatsuya Hashimoto Koichi Suzumori Takefumi Kanda In this paper, we propose a new type of haptic interface, named active link mechanism. This device realizes physical man-machine interaction (PMI) between machines and persons. Two prototypes were developed to demonstrate the potential of the active link mechanisms. Developed interface devices are an active tetrahedron and an active icosahedron. Nine-DOF micro spherical joints and pressure control pneumatic cylinders were developed to realize the active tetrahedron, while fifteen-DOF micro spherical joints and intelligent pneumatic cylinders were developed for the active icosahedron. The tetrahedron successfully realizes "virtual touch"; the operators feel actions, forces, and shapes of the virtual objects in PC and also move and deform them. Real time PMI is realized by building the developed devices into MSC.Visual-Nastran4D. MSC.VisuaI-Nastran4D is a mechanism analysis software, which can make motion analysis in real time. The active icosahedron also realized dynamic interaction with virtual objects in PC, showing the potential of the devices as a haptic interface. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2004 Development of active icosahedron and its application to virtual clay modeling 175 180 EN Jumpei Ochi Tatsuya Hashimoto Junichi Tanaka Koichi Suzumori Takefumi Kanda We have developed an active link mechanism for physical man-machine interaction. We report an active icosahedron consisting of intelligent cylinders and its application to virtual clay modeling. Intelligent pneumatic cylinders are newly developed to realize active link mechanisms. This cylinder aims at a novel cylinder in which various sensors and control devices are built. Active link mechanisms are highly integrated and enhanced by intelligent cylinders. A control system is built for the active icosahedron. In the control system, a key element is a control program implementing drawing of a virtual model on display and controlling of active links. Virtual clays are deformed by the program based on the apex positions converted from cylinder lengths. The active icosahedron realized dynamic interaction with virtual objects in PC, showing the potential of the devices as a haptic interface. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 2005 A cylindrical micro ultrasonic motor using micro-machined piezoelectric vibrator 721 724 EN Takefumi Kanda Akira Makino Yoshitaka Oomori Koichi Suzumori A micro ultrasonic motor using a micro-machined cylindrical bulk piezoelectric vibrator is introduced. This motor consists of the vibrator, a glass case and a rotor. The diameter of the piezoelectric vibrator is 0.8 mm and that of the motor case is 1.8 mm. Since the stator transducer is fixed at the end of the cylinder, it is easy to support the vibrator and the structure of the motor is not complicated. In addition, the vibrator and rotor are supported by the glass case. This is important for the micro ultrasonic motor because it is difficult to support the vibrator when the vibrator is miniaturized. We have fabricated and evaluated the cylindrical shaped traveling type micro ultrasonic motor using this vibrator. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 2003 A miniature inspection robot negotiating pipes of widely varying diameter 2735 2740 EN Koichi Suzumori Shuichi Wakimoto Masanori Tanaka The purpose of this research is to realize a small robot which can negotiate pipes whose diameter varies widely during the robot's course. A new in-pipe locomotion mechanism named "snaking drive" is proposed in this paper and its potential and fundamental characteristics are shown with experimental data of the prototype model. First, in the sections 2 to 5, the basic traveling characteristics of the snaking drive mechanism are discussed: a theoretical formula of the fundamental characteristics and control algorithm are derived, the motions of the robot are simulated on a PC, and the prototype model was designed, developed, and tested. Next, in the sections 6 and 7, additional control algorithms for the front link are derived. They are necessary for steering at T-branches and L-bends of pipes, and also for camera view stabilization. Their performances are also shown by software simulation and experiments. The prototype robots moved in pipes whose diameter varies between 55 mm to 331 mm with the maximum speed of 22 mm/s. The paper also shows that the prototype negotiates T-branches and L-bends of pipes with inspection capability through a camera mounted on the robot. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 2005 Development of intelligent McKibben actuator with built-in soft conductive rubber sensor 745 748 EN Shuichi Wakimoto Koichi Suzumori Takefumi Kanda This study aims at the development of an intelligent McKibben actuator, in which a soft rubber displacement sensor is integrated. Recently, the McKibben actuator has attracted engineers because of light weight, high output power and high compliance. But in the case of using it for servo control at present, the systems need encoders or potentiometers, therefore the systems tend to grow in size and take away from compliance which is an important advantage for a safe and secure mechanism. We have developed a soft displacement sensor and incorporated it in a McKibben actuator, named it the intelligent McKibben actuator, and proved its potential. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 4 2004 Active link mechanisms for physical man-machine interaction 3895 3900 EN J. Ochi Tatsuya Hashimoto Koichi Suzumori J. Tanaka Takefumi Kanda In this paper, we propose a new type of haptic interface, named active link mechanism. This device realizes physical man-machine interaction (PMI) between machines and persons. Two prototypes were developed to demonstrate the potential of the active link mechanisms. Developed interface devices are an active tetrahedron and an active icosahedron. Nine-DOF micro spherical joints and pressure control pneumatic cylinders were developed to realize the active tetrahedron, while fifteen-DOF micro spherical joints and intelligent pneumatic cylinders were developed for the active icosahedron. The tetrahedron successfully realizes "virtual touch"; the operators feel actions, forces, and shapes of the virtual objects in PC and also move and deform them. Real time PMI is realized by building the developed devices into MSC.Visual-Nastran4D. MSC.VisuaI-Nastran4D is a mechanism analysis software, which can make motion analysis in real time. The active icosahedron also realized dynamic interaction with virtual objects in PC, showing the potential of the devices as a haptic interface. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2005 Development of intelligent McKibben actuator 487 492 EN Shuichi Wakimoto Koichi Suzumori Takefumi Kanda The aim of this study is to develop an intelligent McKibben actuator with an integrated soft displacement sensor inside, so that displacement of this actuator can be controlled without having any extra devices attached. In addition, the high compliance which is a positive feature of the McKibben actuator is still conserved. This paper consists of four main parts. First of all, different types of soft displacement sensors made out of rubber were composed, and tested for their functional characteristics. Secondly, the intelligent McKibben actuator was developed with the soft displacement sensor incorporated within. Then, experiments of the position servo control with a single intelligent McKibben actuator were carried out. At last a robot arm mechanism was designed with two intelligent McKibben actuators, and those experimental results showed a great potential for its future applications. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2003 A micro snake-like robot for small pipe inspection 303 308 EN Shuichi Wakimoto Jun Nakajima Masanori Tanaka Takefumi Kanda Koichi Suzumori The goal of this research is development of a micro robot which can negotiate pipes whose diameter varies widely. The robot mechanism is based on "snaking drive". First, in section 1 to 4, basic characteristics of the snaking drive are discussed: the principle of the snaking drive is shown, theoretical fundamental formulas are derived, and the motions of the robot are simulated. Second, in section 5, a micro robot was designed, fabricated and tested. And fundamental experiments of the robot are shown. Third, in section 6, two application experiments are shown: one is a stabilization of camera image, and the other is a robot steering at branches. The robot moved in pipes whose diameter varies between 18 mm to 100 mm with the maximum speed of 36 mm/s. And the robot could negotiate T-branches and L-bends of pipes. No potential conflict of interest relevant to this article was reported.