Enhancing haptic feedback of subsurfaces during needle insertion

Haptic feedback can be helpful for accurate needle insertion but is complicated by friction on the needle shaft. Concepts to directly measure the forces at the needle tip exist but cause additional cost and complexity. Moreover, haptic devices may show inaccuracies in recreating forces. We present a novel force feedback method that uses needle shaft forces and enhances haptic feedback of subsurfaces based on robotic ultrasound elastography. This approach allows to overcome accuracy limitations of haptic devices. We evaluate our method in a volunteer subject study using recordings from a robotic needle driver setup. We compare haptic feedback based on shaft and enhanced force for the detection of surfaces inside of gelatin phantoms. Using our method, the error of subsurface detection decreased from more than 16 to about 1.7 mm for the first subsurface. A second subsurface was solely detectable using our method with an error of only 1.4 mm. Insertion time decreased by more than 32%. The results indicate that our enhanced sensor is suitable to detect subsurfaces for untrained subjects using a haptic feedback device of limited accuracy.

A Wearable Contactless Sensor Suitable for Continuous Simultaneous Monitoring of Respiration and Cardiac Activity

A reliable system that can simultaneously and accurately monitor respiration and cardiac output would have great utility in healthcare applications. In this paper we present a novel approach to creating such a system. This noninvasive, low power, low cost, contactless sensor is suitable for continuous monitoring of respiration (tidal volume) and cardiac stroke volume. Furthermore, it is capable of delivering this data in true volume (i.e., mL). The current embodiment, specifically designed for sleep monitoring applications, requires only 100 mW when powered by a 4.8 V battery pack and is based on the use of a single electroresistive band embedded in a T-shirt. Here, we describe the implementation of the device, explaining the rational and design choices for the electronic circuit and the physical garment together with the preliminary tests performed using one volunteer subject. Comparison of the device with a commercially available spirometer demonstrates that tidal volume can be monitored over extended periods with a precision of ±10%. We further demonstrate the utility of the device to measure cardiac output and respiration effort.

Frontal plane corrective ability of a new unloader orthosis for medial compartment of the knee

Background: Patients with medial compartment osteoarthritis of the knee suffer from pain and stiffness. However, current unloader braces are not being used for extended periods by knee osteoarthritis patients due to interface problems, so compliance is an issue. The aim of this study was to design a new bespoke orthosis that could be comfortable to wear while also providing the required correction to reduce medial compartment loading. Case Description and Methods: A new knee orthosis design was initially tested for its frontal plane correction of knee varus using a surrogate knee model. It was then assessed by a volunteer subject with grade 2 medial compartment knee osteoarthritis using a static standing radiograph. Findings and Outcomes: When fitted to the surrogate knee model, the brace corrected the knee from 10° of varus to neutral alignment in the frontal plane. When worn in situ during static stance on the affected leg of the volunteer patient, it corrected the knee by 6° to a less varus position. Conclusion: The orthosis provided frontal plane correction of the knee during static standing. It could therefore prove to be suitable for use by knee osteoarthritis patients. Clinical relevance This new custom unloader knee orthosis produced a more valgus knee alignment by adjusting the pneumatic components attached to the thigh and leg shells. During static stance, it corrected frontal plane varus knee rotation by 6° in a single subject with knee osteoarthritis.

Volunteer Subject Matter Experts (SMEs) on an eLearning Development Project

Representatives from eight different organizations collaborated to develop a self-paced elearning course to teach preceptor skills to staff nurses in various healthcare organizations. The course employed a constructivist theory of learning and simulated many of the conversations and relationships staff nurses experience when performing preceptor responsibilities. Three of the four subject matter experts were volunteers and never compensated financially for their work on the course. The project manager used an iterative instructional design model and a generic project management methodology. The team considers the project a success because the course is complete, albeit two years later than scheduled, and generating a small amount of revenue. Additionally, the team progressed through the four stages of team development, reaching the “performing” stage, and the course is part of an effective three-pronged solution to avert a potential nursing shortage in the state.

Facilitated Telementoring for K-12 Students and Teachers

The Electronic Emissary is a Web-based service and resource center that helps teachers and students with Internet access locate mentors who are experts in various disciplines, then plan and engage in curriculum-based learning. In this way, the interaction that occurs among teachers and students face-to-face in the classroom is supplemented and extended by electronic mail, Web forum, chat, and audio/videoconferencing exchanges that occur among participating teachers, students, and volunteer mentors. These project-based online conversations typically range in length from six weeks to a full academic year, as students’ needs and interests dictate. The Electronic Emissary has been online since February 1993 and on the World Wide Web since December 1995. It serves students and teachers globally, but the majority of its participants to date have been in North America. Emissary-related research has focused upon the nature of telementoring interactions in which K-12 students are active inquirers, the motivations and perceptions of their volunteer subject matter mentors, why some teachers choose to persist in integrating telementoring into curricula despite considerable hindrances, effective telementoring facilitation techniques, and what teachers learn as they help their students to participate in curriculum-oriented telementoring projects. Students exploring complex curriculum-based topics need to actively build deep and sophisticated understanding. One of the most effective ways to do this is by engaging in ongoing dialogue with knowledgeable others, as the students form, refine, and expand their knowledge. Classroom teachers typically serve as the subject matter experts with whom students interact in curriculum-based areas of inquiry. Yet when the issues being explored are multi-disciplinary, technically and conceptually sophisticated, or dependent upon current and highly specialized research and theory, additional expertise must be made directly available to students and teachers longitudinally, and on an as-needed basis. This is what telementoring offers to learners and educators today, and what the Electronic Emissary brings to students and teachers worldwide.