In this paper, we propose a novel wearable sensor device for the measurement of the head orientation and relative position against the body trunk in real-time. It is known that in natural walking, human locomotion is preceded by changes in head orientation and the walking direction can therefore be predicted by observing the head orientation. We have been developing a wearable sensing device for the measurement of head orientation, which enables prediction of the future walking direction in real-time for the assistive technologies for locomotion — such as exoskeleton robots and wheelchair. Existing body posture measurement devices tend to be large and non-portable, therefore measurement in everyday space is still difficult. On the other hand, the developed system enables wireless and location independent measurement of the orientation of the head and it can be applied for assisted locomotion.

In evaluation of the accuracy of the developed device, we observed the head anticipation during natural walking. Additionally, we compared the head anticipation in natural walking and electric wheelchair locomotion using the developed device and discuss a novel wheelchair control based on head orientation.

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Safety is an important factor for human-machine interface devices. Brake actuated devices are potentially safer than those that rely on motors for force-feedback generation. However, manipulators using conventional frictional brakes do have limitations. This paper presents the experimental evaluation of a newly developed four-state rotary programmable brake in a 2DOF manipulator. The experimental results show improved performance compared to the results obtained when manipulators with conventional frictional brakes are used.

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In this paper we discuss plans initiated to develop and evaluate multisensory displays (i.e. visual, haptic, tactile) to support dismounted (i.e., not in vehicle) Soldier movement, communication, and targeting. Human factors studies of an array of military operational roles have shown significant demand for focal visual attention that diminishes the capacity for task-sharing and attention allocation, especially in the context of unexpected changes and events. If other sensory modalities can be effectively used in a military environment, the benefit could be significant in increasing survivability, information flow, and mission achievement. We discuss operational task demands and two efforts supported from a 2010 SBIR (Small Business Innovative Research) topic.

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This paper presents a modular architecture to develop a wearable system for real-time human motion capture. The system is based on a network of smart inertial measurement units (IMUs) distributed on the human body. Each of these modules is provided with a 32-bit RISC microcontroller (MCU) and miniaturized MEMS sensors: three-axis accelerometer, three-axis gyroscopes, and three-axis magnetometer. The MCU collects measurements from the sensors and implement the sensor fusion algorithm, a quaternion-based extended Kalman filter to estimate the attitude and the gyroscope biases. The design of the proposed IMU, in order to overcome the problems of the commercial solution, aims to improve performance and to reduce size and weight. In this way, it can be easily embedded in a tracksuit for total body motion reconstruction with considerable enhancement of the wearability and comfort. Furthermore, the main achievements will be presented with a performance comparison between the proposed IMU and some commercial platforms.

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Tele-operated robotics has been widely-used to manipulate heavy or hazardous objects in an unknown or dangerous environment. Nowadays, it is adopted in assistive robots to help the elderly in accomplishing household tasks. This paper proposes a hybrid control policy of robot arm motion to semi-automatically control a remote robot arm, which differs from previous work in its hybrid control policy. The motivations of the proposed hybrid control policy are rooted from (1) the safeness in controlling a robot arm in an uncertain environment by tele-operating the robot far from the target position; (2) the quickness in automatically controlling the robot arm close to the target position. By doing this, the robot arm is manipulated to quickly and safely reach to the target position. The proposed hybrid control policy tele-operates a robot by utilizing the joint angles of a human arm to remotely control the robot arm posture where the human joint angles are captured by the proposed motion capture method. To validate the proposed method, we conducted the experimental work on an 6 degree-of-freedom humanoid robot arm. The results showed that the human was able to safely and quickly reach to the manipulative objects by the proposed hybrid control policy of robot arm motion.

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