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We propose a soft capacitive tactile sensor using the displacement of an air–water interface. This soft tactile sensor is composed of a soft contact part with a chamber and channel filled with water and a clip-shaped sensing part to detect the position of the interface. This tactile sensor changes the displacement of the air–water interface in the channel when a contact force is applied. The change in displacement is detected as a change in the capacitance at the sensing part. This sensor structure does not require stiff electrical elements to be embedded in the soft silicone rubber body, which improves the flexibility and durability of the sensor. Therefore, the proposed tactile sensor exhibits high flexibility and durability against bending and external stresses. Additionally, the proposed tactile sensor can detect not only press force but also pull force. This results in the detection of a press or pinch in a robot skin. The experimental results show that the proposed sensor can successfully detect both press and pull static forces. The sensitivity of the proposed sensor was 0.169 pF/N for an applied force in the press direction and −0.152 pF/N for a force in the pull direction based on the results of an evaluation of the static sensor characteristics. Furthermore, an evaluation of the dynamic sensor characteristics revealed that the proposed tactile sensor has high repeatability and a quick response to an external force. Additionally, the hysteresis of the proposed tactile sensor is small, especially in the press direction.

Although three-dimensional imaging can be a powerful tool for dentists to explain treatments to patients, obtaining of three-dimensional image of teeth in general dental clinics is difficult. This paper proposed a method to develop pseudo three-dimensional dental image from conventional dental panoramic radiograph and dental impression. The method estimates imaging parameters of given panoramic radiograph through comparison with dental cast, and re-projects the radiograph into three-dimensional space. The developed pseudo three-dimensional image gives clear impression of the patient’s dental condition.

Virtual reality based force feedback system is spotlighted as a safe and efficient training environment to obtain surgical skills. Neurosurgery utilizes multimodal patient images for visualization of a variety of functions in head. The aim of this study is to establish a concept of multimodal neurosurgery force feedback system based on mesh fusion modeling. In the model of mesh fusion, we developed an algorithm to detect overlapped region between the multiple meshes that are obtained from multimodal images, and to determine a new boundary between the meshes. Then, the method solved interaction between the newly defined mesh boundaries using the interaction model based on a finite element method. The proposed method was implemented, and applied to both simple and patient datasets for evaluating its applicability. As a result, the method succeeded to be applied to both simple and patient datasets. Finally, we demonstrated the early stage of the surgical approach in neurosurgery. Simulation results showed a real-time simulation of brain tissue deformation with force feedback.

The daily medical check is effective to disease prevention. However, visiting a hospital puts a strain to the patients. To solve this problem, this paper proposes newly concept and device for telemedicine. The ubiquitous medical care environment is the concept of the advanced telemedicine system, which realizes the place- and time-independent medical care by dividing people (medical doctor, patient,… etc.). The wearable ultrasound device is a principal equipment of ubiquitous environment, which realize an echography anytime, anywhere. The prototype device is composed of an ultrasound measurement module, compact computer, and small LCD monitor. A proposed system was evaluated by image transmission experiments between prototype device and other computers. Experimental result shows much performance and effectiveness of proposed system.

Augmented Reality is the technology, which augments a real environment in information point of view by superimposing virtual environment on the real world. This paper proposes methods to develop augmented reality environment, where all distributed participants share the same real and virtual environments. This shared augmented reality enables “ put-that-there” communication in cooperative works via networks. This paper presents two example applications. These applications clear advantages of the proposed approach.

We present a novel non-invasive technique for identification of the central sulcus on the brain surface by using three-dimensional magnetic resonance imaging (3D-MRI) in combination with somatosensory evoked magnetic fields (SEFs). The central sulcus was supposed anatomically on the brain surface by using 3D-MRI. On the other hand, the primary somatosensory area is determined by using SEF data with median nerve stimulation. Superimposition of the SEFs of the 25 ms response onto the brain surface MR images clearly demonstrated the dipole source located in the gyral fold just behind the supposed central sulcus in all subjects analyzed. Three-dimensional reconstruction of the brain surface image data facilitated visualizing the precise anatomical localization of the magnetic field activities from any angle and measuring the distance from the source to any point of interest. The potential clinical application of this technique is discussed.