Christian Diaz

Collaborative networked virtual surgical simulators cnvss implementing hybrid client-server architecture: Factors affecting collaborative performance

Currently, surgical skills teaching in medical schools and hospitals is changing, requiring the development of new tools to focus on (i) the importance of the mentor’s role, (ii) teamwork skills training, and (iii) remote training support. Collaborative Networked Virtual Surgical Simulators (CNVSS) allow collaborative training of surgical procedures where remotely located users with different surgical roles can take part in the training session. To provide successful training involving good collaborative performance, CNVSS should guarantee synchronicity in time of the surgical scene viewed by each user and a quick response time which are affected by factors such as users’ machine capabilities and network conditions. To the best of our knowledge, the impact of these factors on the performance of CNVSS implementing hybrid client–server architecture has not been evaluated. In this paper the development of a CNVSS implementing a hybrid client–server architecture and two statistical designs of experiments (DOE) is described by using (i) a fractional factorial DOE and (ii) a central composite DOE, to determine the most influential factors and how these factors affect the collaboration in a CNVSS. From the results obtained, it was concluded that packet loss, bandwidth, and delay have a larger effect on the consistency of the shared virtual environment, whereas bandwidth, server machine capabilities, and delay and interaction between factors bandwidth and packet loss have a larger effect on the time difference and number of errors of the collaborative task.

Adaptive Architecture to Support Context-Aware Collaborative Networked Virtual Surgical Simulators CNVSS

Stand-alone and networked surgical virtual reality based simulators have been proposed as means to train surgical skills with or without a supervisor nearby the student or trainee. However, surgical skills teaching in medicine schools and hospitals is changing, requiring the development of new tools to focus on: i importance of mentors role, ii teamwork skills and iii remote training support. For these reasons a surgical simulator should not only allow the training involving a student and an instructor that are located remotely, but also the collaborative training session involving a group of several students adopting different medical roles during the training session. Collaborative Networked Virtual Surgical Simulators CNVSS allow collaborative training of surgical procedures where remotely located users with different surgical roles can take part in a training session. Several works have addressed the issues related to the development of CNVSS using various strategies. To the best of our knowledge no one has focused on handling heterogeneity in collaborative surgical virtual environments. Handling heterogeneity in this type of collaborative sessions is important because not all remotely located users have homogeneous Internet connections, nor the same interaction devices and displays, nor the same computational resources, among other factors. Additionally, if heterogeneity is not handled properly, it will have an adverse impact on the performance of each user during the collaborative session. In this paper we describe the development of an adaptive architecture with the purpose of implementing a context-aware model for collaborative virtual surgical simulation in order to handle the heterogeneity involved in the collaboration session.

Sistema de Plantillas Instrumentadas “PIEZOMED” destinadas a la valoración del Calzado

In Colombia, there haven’t been reports about the development of an Insole Instrumented system for the footwear industry that contributes in biomechanical design of their models, improving comfort and productivity during design and production of footwear. This article describes the development of the first phase of the instrumented insole system “PIEZOMED”, which has a pair of insoles size 41, evaluated in a male footwear model casual of the Company VELEZ®; the insoles were instrumented with piezoresistive sensors, which had a good linear answer. This first prototype was built wired, looking for a functional design and adaptable for future valuations in footwear. The Software was developed in two parts, the acquisition module, in Labview platform, and the processing and visualization module, in C#.Net. In this phase, the system was built and its performance was tested in casual footwear and visualizing as results: 2D view dynamic, 3D view dynamicm, numeric map, P Vs. t graph, and F Vs. t graph. In a future phase, the system will be developed wireless, with an increased resolution (number of sensors) and tested in a considerable quantity of subjects to evaluate the reliability and validity of the system in contrast with a commercial system. The main aim is to use these insoles for footwear valuation, to support the industry, looking for biomechanical, comfortable, and fashion footwear.