EZ-Manipulator:Designing a mobile,fast,and ambiguity-free 3D manipulation interface using smartphones

Interacting with digital contents in 3 D is an essential task in various applications such as modeling packages, gaming, virtual reality, etc. Traditional interfaces using keyboard and mouse or trackball usually require a non-trivial amount of working space as well as a learning process. We present the design of EZ-Manipulator, a new 3 D manipulation interface using smartphones that supports mobile, fast, and ambiguity-free interaction with 3 D objects. Our system leverages the built-in multi-touch input and gyroscope sensor of smartphones to achieve 9 degrees-of-freedom axis-constrained manipulation and free-form rotation.Using EZ-Manipulator to manipulate objects in 3 D is easy. The user merely has to perform intuitive singleor two-finger gestures and rotate the hand-held device to perform manipulations at fine-grained and coarse levels respectively. We further investigate the ambiguity in manipulation introduced by indirect manipulations using a multi-touch interface, and propose a dynamic virtual camera adjustment to effectively resolve the ambiguity. A preliminary study shows that our system has significant lower task completion time compared to conventional use of a keyboard–mouse interface, and provides a positive user experience to both novices and experts.

A Flexible and Wearable Strain Sensor from Polypyrrole-Doped Elastomers with Dual Functions in Motion Monitoring and Thermotherapy

Flexible strain sensors are essential components of wearable electronic skins.Here we report a new kind of flexible strain sensor by filling conductive nanowires in elastomers featuring a concentration gradient.The fabrication method involves a fast photo-induced copolymerization of acrylates in the presence of gradient deposited polypyrrole(PPy)nanowires,which is facile and cost-effective in steadily doping PPy into elastomeric films.The combination of delicately selected polyacrylates as the matrix filled with entangled,nano-sized PPy endows the sensor good stretchability,sensitive deformation-electrical signal conversion and high fatigue resistance,which can be used repeatedly without scarifying the sensitivity of electrical signal.Besides,the lower side of the composite films exhibits high light absorption(>98%)in a wide spectral range(250—2400 nm).Systematic characterizations of the sensors support that the excellent strain sensing and light-heat conversion performances are essentially dependent on the gradient filling of PPy nanowires.Moreover,the applications of this flexible strain sensor for human motion monitoring and wearable thermotherapy are demonstrated,manifesting a promising option for wearable electronics and personalized healthcare.