Minimally Invasive Surgery (MIS) is one of the most successful applications of surgical robots. Although the introduction of robotic technology has brought a number of benefits, further advancements in MIS are limited by the size and bending radius of instruments. In this paper, we present a compliant four degree-of-freedom manipulator that consists of elastic elements with partly thinner structures. The proposed mechanism allows the elastic element to deform locally, thus minimizing its bending radius while the low number of mechanical parts greatly contributes to its compactness. This paper describes the design strategy, optimization method using FEA, prototype implementation, and evaluations. The evaluations reveal high accuracy and repeat accuracy, which are key elements for robotic instruments in MIS. Further, the prototype is able to exert sufficient force and it is possible to perform a simulated needle insertion task using the manipulator, demonstrating the feasibility of the proposed mechanism.

The Rubber Hand Illusion is a well known multisensory illusion in which the participant feels their own unseen hand become a rubber hand that is placed at the position where their hand is supposedly placed, triggered by synchronized haptic stimuli on their hand and the rubber hand. Our previous study showed that a robotized 1-degree-of-freedom rubber hand in the form of a master-slave system significantly enhanced the illusion compared with the classic rubber hand illusion. The illusion gives the sense that the part of body becomes part of the robot - it is thus assumed that this multisensory illusion is a potentially effective way to increase intuitiveness, and therefore increase the operability of a multi-degrees-of-freedom master-slave system. To further investigate the concept, we built a multisensory illusion inducible microsurgical robotic system based on the findings of the previous study and conducted a series of psychophysical experiments. The experimental results reveal that the multisensory illusion and operability is significantly correlated.

Up to now, there are different kinds of robot-assisted ultrasound diagnostic systems proposed in the last decade. However, the compensation of the ultrasound probe position according to the patient movement is still one of the most important and useful functions required for those systems. For this purpose, in this research, we aim at developing an automated diagnostic system for the measurement of the wave intensity which is usually measured at the common carotid artery. In particular, in this paper, we focus on proposing a robust visual servoing method for tracking out-of-plane motion for a robot-assisted medical ultrasound diagnostic system by using a conventional 2D probe. A robotic device which manipulates the ultrasound probe firstly scans a small area around the target position and records several B-mode images at a regular interval. In order to track the out-of-plane motion, an inter-frame block matching method has been proposed and implemented on the Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement System No. 2 Refined (WTA-2R). A set of experiments was proposed to verify the effectiveness of the proposed method. From the experimental results, we could confirm its robustness while doing the task with real human tissues.

In this paper, we present a robotic system which automatically searches and detects the longitudinal section of the carotid artery using a conventional medical ultrasound diagnostic system. In order to obtain a clear image of the carotid artery ready for medical diagnosis, the authors developed real-time image processing algorithms to detect the carotid artery and tissue layers of its walls in the B-mode ultrasound images. Sequential patterns of the ultrasound probe trajectory for scanning the surface of the neck and searching the carotid, were implemented and tested on the Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement Robot System No. 1 Refined II (WTA-1RII). An experiment with eleven volunteers was carried out and the results show that the system obtained clear images of the carotid artery in 91% of the trials.

In recent years, due to the increasing rate of elderly people in Japan, the needs to detect adults' diseases at the early stage becomes a high priority. In particular, an increased interest in detecting heart and cerebrovascular diseases at an early stage may allow clinicians to begin treatment sooner, when interventions are generally more effective and less expensive. Recently, the wave intensity (WI) has been proposed as a new hemodynamic index that provides information about the dynamic behavior of the heart and the vascular system and their interaction. However; the repetitiveness and accuracy of the WI measurement depend on the precision of the positioning of the ultrasound probe. Therefore a positioning device for ultrasound probe is required. Such a device should not only be used to keep the position but also for the fine positioning of the probe. For this purpose, at Waseda University, we have proposed the development of a robot system to assist a carotid blood flow measurement using ultrasound diagnostic equipments. In this paper, the development of Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement System No. 1 Refined II (WTA-1RII) is detailed. The system consists of an ultrasound diagnostic device, a 6-DOFs parallel link manipulator, a serial link passive arm, ball joint, and a joystick type controller. The WTA-1RII has improved the design of the gravity compensation mechanism. In addition, a genetic algorithm has by implemented to determine the optimal link's position of the 6-DOFs parallel manipulator to increase the workspace. Finally, a set of experiments were carried out to determine the usability of the proposed system.

The rapidly increase of personal robotic platforms and their applications in Japan represents a great challenge for universities to introduce undergraduate students the basic knowledge required to develop intelligent automated mechanisms. For this purpose; in this paper, we are presenting our approach to introduce first year undergraduate students of the Department of Modern Mechanical Engineering the basics of robotics systems. In order to foster the creativity of undergraduate students of engineering fields, we focused in developing an education tool designed to introduce at different educational levels the principle of developing mechatronic systems. In particular, the development of an inverted pendulum mobile robot Waseda Wheeled Vehicle No. 2 (WV-2R) has been proposed. Different kinds of experiments were proposed to confirm the possibility of implementing controllers as well as changing physical properties of the system to observe differences on the response of the system. From the experimental results, we could confirm the effectiveness of the proposed systems to control the angle of pendulum respect to the body base as well as by changing the radius of the wheel.

The rapidly increase of personal robotic platforms and their applications in Japan represents a great challenge for universities to introduce undergraduate students the basic knowledge required to develop intelligent automated mechanisms. For this purpose; in this paper, we are presenting our approach to introduce first year undergraduate students of the Department of Modern Mechanical Engineering the basics of robotics systems. In particular, the details of curricula of the Mechatronics Laboratory (1) and (2) are explained. In both lessons, the students receive lectures of the content of each proposed topic and then, a set of practical experiments are done. On the other hand, in order to foster the creativity of undergraduate students of engineering fields, we focused in developing an education tool designed to introduce at different educational levels the principle of developing mechatronic systems. In particular, the development of an inverted pendulum mobile robot Waseda Wheeled Vehicle No. 2R (WV-2R) has been proposed. Regarding the Mechatronics Laboratory, questionnaires were proposed to obtain information from the students about their impressions of the lessons. From the comments collected from the questionnaires, we observed the advantages of the proposed curricula to introduce them about robot technology. On the other hand, different kinds of experiments were proposed to confirm the possibility of implementing controllers as well as changing physical properties of the system to observe differences on the response of the system.