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There are currently many quadruped robots suited to a wide range of applications, but traversing some terrains, such as vertical ladders, remains an open challenge. There is still a need to develop adaptive robots that can walk and climb efficiently. This paper presents an adaptive quadruped robot that, by mimicking feline structure, supports several novel capabilities. We design a novel paw structure and several point-cloud-based sensory structures incorporating a quad-composite time-of-flight sensor and a dual-laser range finder. The proposed robot is equipped with physical and cognitive capabilities which include: 1) a dynamic-density topological map building with attention model, 2) affordance perception using the topological map, and 3) a neural-based locomotion model. The novel capabilities show strong integration between locomotion and internal–external sensory information, enabling short-term adaptations in response to environmental changes. The robot performed well in several situations: walking on natural terrain, walking with a leg malfunction, avoiding a sudden obstacle, climbing a vertical ladder. Further, we consider current problems and future development.

Recently, research on flapping robots inspired by the behavior of insects and birds has become a focus of attention in the fields of robotics and biomimetics. However, most flapping robots require an operator or an assistance device to take off. The goal of this study was to develop a flapping robot that can achieve self-takeoff without running and can be used like a drone. This paper describes the development and evaluation of the flapping robot developed with this aim. The developed robot can generate a thrust that exceeds its own weight with a simple flapping mechanism and a lightweight design. The airspeed was simulated using the thrust measured with a force sensor and the resistance coefficient estimated in a gliding experiment, and it was found to exceed the minimum airspeed required to achieve takeoff 0.3 s from the onset of flapping. The result of the takeoff experiment demonstrated that takeoff was possible if the initial pitch angle was high. However, the pitch angle decreased immediately after takeoff due to the pitching moment generated by the flapping motion. The moment on the tail wing was not enough for the robot to maintain a horizontal posture at low airspeeds during takeoff. It was concluded that the robot requires a control mechanism for the pitching moment generated by the flapping motion and/or accelerators that function without flapping during takeoff, such as hind limbs. Therefore, the parameters required for the design of actuated hind limbs were estimated.

This paper describes an air-coupled ultrasound system by using DIO-2000. The system is aimed to use for inner muscle evaluation in rehabilitation process. The system evaluates inner muscle with low constrain than conventional method which measured by using MR image, X-ray CT and contacted ultrasound system. Our air-coupled ultrasound system measures transmitted ultrasound wave with very low power through human abdominal region by employing a pulsar-receiver with high sensitive preamplifier, and wave detection method based on fuzzy inference finds transmitted wave from noisy wave. The fuzzy inference is derived from characteristics of transmitted wave. In the experiment, we evaluate the accuracies of wave detection method for human body.

This paper proposes a real-time feature extraction and segmentation method for a 3D point cloud. First of all, we apply Growing Neural Gas with Utility (GNG-U) to the point cloud for learning a topological structure. However, the standard GNG-U cannot learn the topological structure of 3D space environment and color information simultaneously. To this end, we then modify the GNG-U algorithm by using a weight vector. we propose a surface feature extraction and segmentation method by efficiently utilizing the topological structure. Our segmentation method is based on a region growing method whose similarity value uses the inner value of two normal vectors connected by the topological structure. We show experimental results of the proposed method and discuss the effectiveness of the proposed method.

This paper proposes a 3D point cloud segmentation method using a reflection intensity of Laser Range Finder LRF. In this paper, we use LRF and tilt unit for acquiring a 3D point cloud. First of all, we apply Growing Neural Gas GNG to the point cloud for learning a topological structure of the point cloud. Next, we proposed a segmentation method based on an intensity histogram that is composed of the nearest data of each node. Finally, we show experimental results of the proposed method and discuss the effectiveness of the proposed method.

An isokinetic exercise is one of the training methods. Servomechanism using electric motor has been used for isoki netic exercise system. But, isokinetic exercises can be realized by using passive devices such as brakes or dampers. Since such passive systems are inherently safe, they are suitable for mechanical systems which are operated by hu man beings. In this study, we develop the brake using particle-type ER fluid. ER fluid is a fluid whose rheological characteristics can be controlled by electric field. ER brakes can response very quickly and have the characteristics like Coulomb friction. Then, we discuss the velocity control of ER brake system. Finally we confirmed the validity of the proposed method by control experiments.

In these days, patients and doctors in operation room are surrounded by many medical devices as resulting from recent advancement of medical technology. However, these cutting-edge medical devices are working independently and not collaborating with each other, even though the collaborations between these devices such as navigation systems and medical imaging devices are becoming very important for accomplishing complex surgical tasks (such as a tumor removal procedure while checking the tumor location in neurosurgery). On the other hand, several surgical robots have been commercialized, and are becoming common. However, these surgical robots are not open for collaborations with external medical devices in these days. A cutting-edge "intelligent surgical robot" will be possible in collaborating with surgical robots, various kinds of sensors, navigation system and so on. On the other hand, most of the academic software developments for surgical robots are "home-made" in their research institutions and not open to the public. Therefore, open source control software for surgical robots can be beneficial in this field. From these perspectives, we developed Open Core Control software for surgical robots to overcome these challenges.In general, control softwares have hardware dependencies based on actuators, sensors and various kinds of internal devices. Therefore, these control softwares cannot be used on different types of robots without modifications. However, the structure of the Open Core Control software can be reused for various types of robots by abstracting hardware dependent parts. In addition, network connectivity is crucial for collaboration between advanced medical devices. The OpenIGTLink is adopted in Interface class which plays a role to communicate with external medical devices. At the same time, it is essential to maintain the stable operation within the asynchronous data transactions through network. In the Open Core Control software, several techniques for this purpose were introduced. Virtual fixture is well known technique as a "force guide" for supporting operators to perform precise manipulation by using a master-slave robot. The virtual fixture for precise and safety surgery was implemented on the system to demonstrate an idea of high-level collaboration between a surgical robot and a navigation system. The extension of virtual fixture is not a part of the Open Core Control system, however, the function such as virtual fixture cannot be realized without a tight collaboration between cutting-edge medical devices. By using the virtual fixture, operators can pre-define an accessible area on the navigation system, and the area information can be transferred to the robot. In this manner, the surgical console generates the reflection force when the operator tries to get out from the pre-defined accessible area during surgery.The Open Core Control software was implemented on a surgical master-slave robot and stable operation was observed in a motion test. The tip of the surgical robot was displayed on a navigation system by connecting the surgical robot with a 3D position sensor through the OpenIGTLink. The accessible area was pre-defined before the operation, and the virtual fixture was displayed as a "force guide" on the surgical console. In addition, the system showed stable performance in a duration test with network disturbance.In this paper, a design of the Open Core Control software for surgical robots and the implementation of virtual fixture were described. The Open Core Control software was implemented on a surgical robot system and showed stable performance in high-level collaboration works. The Open Core Control software is developed to be a widely used platform of surgical robots. Safety issues are essential for control software of these complex medical devices. It is important to follow the global specifications such as a FDA requirement "General Principles of Software Validation" or IEC62304. For following these regulations, it is important to develop a self-test environment. Therefore, a test environment is now under development to test various interference in operation room such as a noise of electric knife by considering safety and test environment regulations such as ISO13849 and IEC60508. The Open Core Control software is currently being developed software in open-source manner and available on the Internet. A communization of software interface is becoming a major trend in this field. Based on this perspective, the Open Core Control software can be expected to bring contributions in this field.

In this paper, we provide a perspective of touch technology. Two illustrative examples are shown here to explain the potential of touch technology. One is TouchLens, a new type of haptic devices different from tactile sensors and displays. Through this haptic device by our hand we can perceive geometric information of tiny bumps and holes that are difficult to be detected by our bare hand. TouchLens is not only useful for inspections in manufacturing but also attractive as a fun haptic tool by which everyone can understand the power of haptic technology easily. The other relates to a haptic illusion called the velvet hand illusion in which we can feel an illusory surface with strange velvety, slippery or oily texture when we lightly rub a wire mesh of hexagonal pattern between our hands, keeping our hands pressed gently together. We found that moving line stimuli were also effective for eliciting the velvet hand illusion. The observed illusory phenomena caused by a variety of moving line stimuli allow us to see the underlying mechanism of human tactile information processing. Because the obtained illusory sensation is very impressive, it is expected that the illusion can be utilized as a main effect of a new type of haptic display.

Here we show a tactile sensing for human-centered robotics. One is a multi-fingered hand system for telepresence based on the tactile information. The soft finger with the built-in compact tactile sensor is discussed from a biomimetic viewpoint. Another is a tactile enhancing tool that operates not only as a disturbance filter, but also, supposedly, as a magnifier of surface undulation. A simple physics is utilized to generate the enhancing effect.

In this paper, we report some observations related to a haptic illusion called the velvet hand illusion (VHI) in which we can feel a strange velvety sensation when we lightly rub a wire mesh of hexagonal pattern between our hands, keeping our hands pressed gently together. Moving line stimuli are used to find the conditions for eliciting the illusion in order to understand its mechanism deeply.