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Surface acoustic waves (SAWs) are used in many applications. Here, we consider application of SAWs to actuators, which require relatively large vibration amplitudes. In conventional applications, a SAW propagates on a LiNbO3 substrate that serves as an elastic medium. This implies that the maximal size of a SAW transducer is limited by the LiNbO3 wafer size. Better actuators require larger-size SAW transducers. Here, we propose a transducer in which an excited SAW propagates on an inexpensive elastic medium (indirect excitation method). The method combines a piezoelectric material and a non-piezoelectric material substrate. These two materials are coupled. Electric energy is provided by an interdigital transducer (IDT). We designed and studied three different transducer configurations. To determine the optimal configuration, various materials and their combinations were considered with the proposed method. Electrical and mechanical characteristics were quantified in terms of the frequency response of admittance and vibration response, respectively. A suitable combination of materials was determined after measuring and analyzing the properties of different transducers. For this combination, the vibration velocity of the novel transducer was as large as that obtained using the conventional direct excitation method.

A method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A stator transducer material (piezoelectric material) of a SAW tactile display, however, had constraint of size and shape. Previously, to solve this problem, a new method was proposed to excite and propagate SAW on a non-piezoelectric material surface. Excitation and propagation of SAW on a non-piezoelectric material is realized by combination of a LiNbO 3 plate and a glass substrate. Using the method, the glass substrate SAW tactile display could realize tactile sensation in the same manner as the conventional SAW tactile display. However, a relationship between the friction coefficient and vibration amplitude is unclear in the glass substrate SAW tactile display. To decide and optimize the control parameters of the glass substrate SAW tactile display, the relation is needed. In this research, the friction shifts was experimentally confirmed in the glass substrate SAW tactile display. Additionally, the relation was investigated.

A surface acoustic wave (SAW) linear motor is a kind of ultrasonic motor. The advantages of the SAW linear motor are thin structure, high thrust force, high velocity and precise positioning. The relationship between applied current and output velocity is, however, unstable in the low velocity range due to the friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control in the low-velocity region. In this research, to realize low velocity, a pulse width modulation (PWM) control and flexible slider structure are employed. Flexible structure is installed to cancel vibration due to the PWM carrier wave. A lower velocity in the unstable range is realized. Moreover we change the calculation algorithm for the slider velocity measurement. As a result, the SAW linear motor can be driven at an ultra low velocity of 30μm/s. Additionally, driving characteristics are improved using a feedforward controller.

We report a patient who had a 4-year history of adult-onset Still's disease (AOSD) and showed a prominent increase in large granular lymphocytes (LGL) when she developed severe Pseudomonas conjunctivitis due to Pseudomonas aeruginosa, skin eruptions, liver damage, and abnormal findings in coagulation studies, without any evidence of active viral activation, hemophagocytosis, or malignancies. The increased LGL cells were CD3(+)CD8(+), and disappeared promptly after the administration of antibiotics combined with prednisolone, with subsequent stabilization of her general condition.

Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The SAW linear motor has several advantages, such as thin structure, high thrust force, high velocity and precise positioning. Relationship between applied voltage and output velocity, however, had non-linearity in low velocity range due to friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control at low velocity. To realize low velocity, PWM (pulse width modulation) control and flexible slider structure are employed. The flexible structure is installed to cancel vibration due to PWM carrier frequency. In this research, PWM is applied for controlling the slider velocity. Lower velocity in non-linear range is realized. Influence of the flexible structure upon precise positioning is investigated.

This paper describes a novel method to indicate tactile sensation through a PC mouse using friction control applying surface acoustic wave (SAW). For the friction control, a wave-circulating SAW transducer is proposed. In the structure, the wave excited by the oscillator can circulate around the substrate surface to improve energy efficiency. In this research, a tactile mouse, which is a computer mouse with tactile feedback, is proposed. The tactile feedback applying the friction control is described. The friction between the mouse and a mouse pad can be controlled by mechanical vibration of the SAW. Fabrication and characteristics of the SAW transducer are indicated. Successful work of the tactile mouse is also reported.

This paper is concerned with stability curves and capsizing of a ship in severe quartering waves. The effects of wave height, wave length and heading angles of ship to waves on stability curve are analytically investigated for a container ship. A time domain numerical simulation program for motions and capsizing has been used to investigate motions in a variety of wave configulations. Numerical simulations based on a mathematical model are carried out to predict critical situation leading up to capsizing of a container ship in severe quartering waves. Various phisical mechanism that could be responsible for capsize are pointed out by numerical experiments.

A surface acoustic wave (SAW) linear motor is a kind of ultrasonic motor, which has many merits such as thin structure, easy installation and so on. The motor, however, has a problem with wear of contact surface due to its driving principle. Diamond-like carbon (DLC) film have been recognized as a wear-resistant material. In this research, segment-structured DLC (S-DLC) films have been applied to the stator transducer surface. However, exfoliations of the S-DLC films and insufficient driving performance were observed. This paper proposes a new preparing method for the segment structure on the stator transducer and describes the prepared surface. Driving surface abrasion test result is also reported. Maximum coefficient of static friction of the proposed motor is compared with that of a conventional motor. Driving characteristics observation result is also included.

Recently, pen-tablet interface for PC has been commercialized. Using the device, its user can draw a line on it as well as point icons like a mouse. During such operation, users can feel only smoothness on the top of the pen. They cannot recognize the completion of the operation, because of no tactile sensation feedback. In this research, tactile feedback through the pen is proposed. The operators can feel drawing sensation similar to the feeling when they draw a line with a charcoal on a drawing paper. To realize the feedback, principle of surface acoustic wave (SAW) tactile display was applied. A movable tablet with a SAW transducer was designed and fabricated. With the transducer, tactile feedback can be enjoyed on whole PC screen.

This paper describes development of a pen tablet type surface acoustic wave (SAW) tactile display. Combination of the device with a Phantom is proposed to control the display. The role of the Phantom is to detect pen position and to guide the pen inside the indication area of the display. This paper presents principle of the SAW tactile display and its application to pen tablet interface. The combination to realize our proposal is also indicated. Demonstration is reported to show effectiveness of the developed device.

A surface acoustic wave (SAW) linear motor is a kind of ultrasonic motor. The advantages of the SAWlinear motor are its thin structure, high thrust force, high velocity and precise positioning. However, the stator transducer material (piezoelectric material) of the SAW linear motor has constraints of size and shape. To resolve this problem, a method is proposed to excite and propagate a SAW on a non-piezoelectric material surface. Excitation and propagation of the SAW on the non-piezoelectric material is realized by the combination of a LiNbO3 plate and a glass substrate. The design and fabrication of the glass substrate transducer for the SAW linear motor are described. The design employs a novel transducer structure, which has been proposed previously. SAW excitation on the glass substrate stator transducer is applied for the SAW linear motor. The fabricated motor worked successfully. Driving characteristics of the glass substrate SAW linear motor are also reported.

This paper describes development of a pen tablet type surface acoustic wave (SAW) tactile display. Combination of the device with a pen tablet LCD device is proposed. The role of the device is to detect pen position and to provide visual information. This paper presents principle of the SAW tactile display and its application to pen tablet interface integrated with visual information. The combination to realize our proposal is also indicated. Demonstration method and measurement result of mechanical vibration of the pen are also reported.

A 58-year-old female with systemic lupus erythematosus (SLE) and anti-phospholipid syndrome (APS) was referred and admitted to our hospital because of fever and pancytopenia. She had been taking small dose of prednisolone and azathiprine since 2003 with stable SLE and APS. Two weeks before the admission, she developed fever and common cold-like symptoms and was admitted to a hospital. Antibiotics were ineffective and thrombocytopenia manifested. Under a diagnosis of progressive SLE, bolus methylprednisolone was administrated. However, she became pancytopenic and was transferred to our hospital. A bone marrow aspirate showed the hemophagocytosis and chest CT scanning revealed interstitial pneumonia. Cytomegalovirus (CMV) antigenemia test gave a positive result. A diagnosis of CMV-induced hemophagocytic syndrome (HPS) and CMV pneumonia was made. Gancyclovir resolved the pancytopenia, pneumonia, and fever. There have been only 3 reported cases of CMV-related HPS in collagen disease.

This paper deals with proposal of a pen tablet interface combined with visual information. The interface employs surface acoustic wave (SAW) tactile display. Basic principle of the tactile display and its application for our proposal are described. Design and fabrication of an ultrasonic transducer are also reported. Development of the proposed interface using the same controller as the conventional SAW tactile display is explained. Measurement result of vibration on the top of the pen indicates realization of the proposed interface.

A surface acoustic wave (SAW) linear motor, which is a kind of ultrasonic motors, has many merits such as thin structure, large force, high speed, precise positioning and so on. On the other hand, wear is one of problems in the motor due to friction drive principle. Diamond-like carbon (DLC) films have been recognized as a wear resistant material. In this research, segment structured DLC films are focused to avoid the DLC property of easy damage. Installation of the films to friction surface of the motor is reported. Measurement result of its driving characteristics is also described.

This paper deals with proposal of a pen tablet interface combined with surface acoustic wave (SAW) tactile display. Basic principle of the tactile display and its application for our proposal are described. Design and fabrication of an ultrasonic transducer are also reported. Development of the proposed interface using the same controller as the conventional SAW tactile display is explained. Measurement result of vibration on the top of the pen indicates realization of the proposed interface.

A method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A stator transducer material (piezoelectric material) of a SAW tactile display, however, had constraint of size and shape. In this research, to solve this problem, a new method has been proposed to excite and propagate SAW on a non-piezoelectric material surface. Excitation and propagation of SAW on a non-piezoelectric material is realized by a combination of a LiNbO3 plate and a glass substrate. This paper describes design and fabrication of a large sized glass substrate transducer for the novel method to indicate tactile sensation using SAW. The design employs the novel transducer structure, which has been proposed previously. Using the transducer, two-dimensional rubbing motion is available. This paper also reports measurement result of speed of a slider under control. The result indicates successful display of roughness sensation based on the tactile display principle proposed by authors.

We had proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage is applied to reproduce human tactile sensation. To expand its application, a glass substrate SAW transducer has been proposed. The glass substrate transducer worked successfully. In the application, however, user's rubbing motion was limited to one-dimensional motion. To expand tactile display application, a wide and long transducer would be required. Such a transducer can realize two-dimensional tactile display. To improve energy efficiency, a new design of the transducer was proposed. This paper describes design of the new glass substrate transducer and its fabrication. Characteristics of the transducer are also reported.

We have already proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). In this paper, we propose "tele-touch", which realize reproduction of tactile sensation as if to rub remote solid surface. To generate tactile display control parameters, object surface is measured by a fabricated profile scanner. Control parameters are generated from the result. To indicate various texture, we install amplitude modulation for SAW excitation. Demonstration to reproduce the tactile feeling of sample surface with the control parameters and the modulation drive is carried out.

Previously, a novel method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A stator transducer material (piezoelectric material) of a SAW tactile display, however, had constraint of size and shape. In this research, to solve this problem, a new method is proposed to excite and propagate SAW on a non-piezoelectric material surface. Excitation and propagation of SAW on a non-piezoelectric material is realized by a combination of a LiNbO3 plate and a glass substrate. Successful work of an active type SAW tactile display using the glass transducer is reported. Additionally, installation of the glass transducer on an LCD to indicate tactile sensation with visual information and its demonstration are described.

We have already proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of standing SAW. The distribution generates friction shift on the surface of a SAW substrate. When the surface with the burst SAW is explored through a slider by a finger, the friction shift generates a mechanical vibration similar to a stick-slip vibration on the finger. The vibration can be perceived as tactile sensation at mechanoreceptors in the finger skin. Controlling the burst frequency according to measured rubbing motion, reality of the displayed sensation can be enhanced. In this research, we install the tactile display with a transparent stator transducer on a computer screen. Two-dimensional rubbing motion is available for the display. An experimental apparatus with finger motion capture system is fabricated on trial and controlled according to the captured motion. In a demonstration, operators can rub on a solid mark under the display to recognize its shape through tactile sensation.

For reproduction of human tactile sensation, a tactile display using surface acoustic wave (SAW) has been proposed. To expand application of the device that has constrains due to its configuration, a novel SAW excitation method is proposed. A glass substrate, which is non-piezoelectric material, is combined with a piezoelectric material. A glass substrate SAW transducer is fabricated on trial. Measuring results of its characteristics indicates the transducer has enough performance. The tactile display employing the glass transducer works successfully.

This paper describes a new method to excite and propagate surface acoustic wave on a non-piezoelectric material surface. The method contains a combination of a LiNbO3 piece and a glass substrate. Successful work of an active type SAW tactile display using the glass transducer is reported. Additionally, installation of the glass transducer on an LCD to indicate tactile sensation with visual information and its demonstration are described.

This paper describes a novel method to indicate tactile sensation using surface acoustic wave (SAW). With standing wave of SAW, friction of a transducer surface was shifted. Switching the wave according to operator's action, roughness sensation when we rub on a solid surface could be enjoyed. A SAW tactile display and a controller with the finger action detector were fabricated. Roughness sensation and its difference could be indicated successfully.

A surface acoustic wave (SAW) tactile display consisted of a piezoelectric substrate and a slider. Rubbing the substrate through the slider, we could feel tactile sensations under a control depending on the rubbing motion. On the other hand, the piezoelectric substrate had constraint of size and shape. In this research, to solve this issue, a method was proposed to excite and propagate a SAW on a non-piezoelectric material surface. The method was realized by combination of a LiNbO/sub 3/ plate and a glass substrate. Characteristics were measured. The effectiveness of the proposed method for the tactile display was discussed. An active type SAW tactile display using the glass transducer worked successfully.

This paper introduces integration of a force feedback device and a tactile display. The tactile display uses progressive surface acoustic wave and is installed on a stylus of Phantom as the force feedback device. The integrated system works successfully.

We have already proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of standing SAW. The distribution generates friction shift on the surface of a SAW substrate. When the surface with the burst SAW is explored, the friction shift can be perceived as tactile sensation at mechanoreceptors in the finger skin. Controlling the burst frequency according to measured rubbing motion, reality of the displayed sensation can be enhanced. In this paper, we proposed a transparent tactile display. An experimental apparatus was fabricated on trial and controlled by using captured images. The apparatus demonstrated potentiality of the tactile display for various applications.

A musical rhythm is expressed by the number of the timing marks (for example, three timing marks when in simple triple time); and a musical tempo is expressed by the distance among the timing marks and a timing ball that moves at a fixed speed among those timing marks. Accordingly, a player may easily grasp the tempo of the music and easily determine the rhythm of the music in a sound game.