A flexible, three-axis carbon nanotube (CNT)–polymer composite-based tactile sensor is presented. The proposed sensor consists of a flexible substrate, four sensing cells, and a bump structure. A CNT–polydimethylsiloxane (PDMS) composite is produced by a solvent evaporation method, and thus, the CNTs are well-dispersed within the PDMS matrix. The composite is directly patterned onto a flexible substrate using a screen printing technique to fabricate a sensor with four sensing cells. When a force is applied on the bump, the magnitude and direction of force could be detected by comparing the changes in electrical resistance of each sensing cell caused by the piezoresistive effect of the composite. The experimentally verified sensing characteristics of the fabricated sensor exhibit a linear relationship between the resistance change and the applied force, and the measured sensitivities of the sensor for the normal and shear forces are 6.67 and 86.7%/N for forces up to 2.0 and 0.5 N, respectively. Experiments to verify the load-sensing repeatability show a maximum 2.00% deviation of the resistance change within the tested force range.

The combined tactile and kinesthetic feedback of the master device in robotic surgery improves the surgeon's ability to control the interaction force applied to the tissue. Copyright © 2014 John Wiley & Sons, Ltd.

Although haptic feedback is critical for many surgical tasks, surgeons cannot currently obtain haptic feedback from teleoperated surgical robots because it is difficult to attach force sensitive sensors to the surgical robot in the surgery environment. Therefore, force sensitive forceps with an optical fibre Bragg grating sensor attached on the grasper are proposed. The proposed prototype forceps confirmed that the sensitive grasping force in the teleoperated grasper is comparable to the providing force and measuring force.

Touchscreen interaction has become a fundamental means of controlling mobile phones and smartwatches. However, the small form factor of a smartwatch limits the available interactive surface area. To overcome this limitation, we propose the expansion of the touch region of the screen to the back of the user’s hand. We developed a touch module for sensing the touched finger position on the back of the hand using infrared (IR) line image sensors, based on the calibrated IR intensity and the maximum intensity region of an IR array. For complete touch-sensing solution, a gyroscope installed in the smartwatch is used to read the wrist gestures. The gyroscope incorporates a dynamic time warping gesture recognition algorithm for eliminating unintended touch inputs during the free motion of the wrist while wearing the smartwatch. The prototype of the developed sensing module was implemented in a commercial smartwatch, and it was confirmed that the sensed positional information of the finger when it was used to touch the back of the hand could be used to control the smartwatch graphical user interface. Our system not only affords a novel experience for smartwatch users, but also provides a basis for developing other useful interfaces.

In spite of the radical enhancement of web technologies, many users still continue to experience severe difficulties in navigating web systems. One way to reduce the navigation difficulties is to provide context information that explains the current situation of users in the web systems. In this study, we empirically examined the effects of two types of context information, namely, structural and temporal context. In the experiment, we evaluated the effectiveness of the contextual navigation aids in two different types of web systems: an electronic commerce system and a content dissemination system. In our experiment, subjects performed several browsing tasks and answered a set of post-questionnaires. The results of the experiment reveal that the two types of contextual navigation aids significantly improved the performance of browsing tasks regardless of different web systems. Moreover, context information changed the users' navigation patterns, and increased their subjective ease of navigation. This study concludes with implications for understanding the users' browsing patterns and for developing effective navigation systems.