The advent of wireless technology and Internet accessibility has transformed our ability to interact in a variety of levels and platforms, including the classroom, the workplace and leisure activities. In the area of information technology, Drexel University faculty are involved in a variety of topics including medical robotics, wireless communication, signal processing, and telecommunications. Drexel University leads a consortium of educational and industrial concerns at the $12.5M Center for Applied Communications and Information Networking. Drexel is also home to the $7.5M Pegasus Project, which is dedicated to the development of the next generation of Internet. Below are some of the projects that the RET Fellows will be directly involved with along with the faculty mentor names.
1) Medical Robotics (with Dr. Jaydev P. Desai – NSF CAREER awardee)
The primary goal of this component in technological education of the teacher workforce in the Philadelphia school district is to create an
inquisitive mind-set for the teachers to explore and understand the role of emerging technologies in the area of medical robotics with particular emphasis on minimally invasive procedures. Minimally invasive surgical procedures using long instruments deprive the surgeon of depth perception, dexterity, sense of touch, and excellent hand eye coordination, that they are so accustomed to in open procedures. What the surgeon loses presents excellent theoretical, experimental, and developmental opportunities for the engineer to develop “smarter” and efficient systems for use in minimally invasive surgery. This consequently leads to better patient care, reduced morbidity, shorter hospital stay, reduced trauma, faster recovery times, and lower health care costs. Cancer of the liver is the second leading cause of death in the United States and worldwide (next to lung cancer) and it is rapidly coming close to being one of the leading causes of death. Each year about 28,000 cases are diagnosed and almost as many patients die of advanced disease (these statistics have been obtained through private communication with collaborating surgeons). The fundamental questions in haptics (sense of touch) and robot vision answered through our research in laparoscopic hepatic tumor resection (removing liver tumors) using robotic techniques will be taught to the teachers and how it can benefit other minimally invasive procedures performed in: a) kidney (laparoscopic renal resection) b) pancreas, and c) adrenals (such as partial laparoscopic adrenalectomy). A schematic of the proposed robotic system for gastrointestinal procedures is shown in Figure 4 where the robot in collaboration with the surgeon is working on removing a hepatic tumor through minimally invasive techniques while being assisted by a surgical assistant.
To achieve a surgical robotic system shown in Figure 5, it is necessary to design and develop the principal technologies and research various haptic and tactile sensing mechanisms for transmitting the necessary feedback to the surgeon interacting with a haptic feedback device. Figure 5 shows our present instrumented laparoscopic grasper capable of providing force and position feedback to the operator through a haptic feedback device. Our interaction with the teachers will focus on educating the teachers with the tools and software that will allow haptic feedback to be integrated in a robotically assisted gastrointestinal procedure. One of the initial tasks will be to develop artificial tissues to replicate the real tissues palpated by the surgeons in gastrointestinal procedures. Developing these tissues in the laboratory environment will be accomplished with our close collaboration with Dr. Michele Marcolongo (Co-PI on this proposal). Using this tissue, we can develop a novel setup whereby tactile feedback from the laparoscopic tool is displayed on the PHANToM, a haptic interface device in real time. This can be used for tissue characterization and classification. The teachers will be involved in various stages of this research from design, development and testing of their tissues with haptic feedback devices currently present in our laboratory (purchased through the NSF Major Research Instrumentation Award).
2) Wireless Communications - (Dr. Kapil Dandekar)
A primary challenge in the teaching of high school level physics is the ability to convey intuition for complex processes in nature. High school students in physics generally find topics in mechanics to be more accessible than electricity and magnetism for this reason. The goal of this component of high school teacher technical education is to allow for a visualization-based exploration of signal propagation in wireless communications systems. This research opportunity will apply advanced computational electromagnetics (CEM) techniques with desktop virtual reality to develop a web-based tool that can help teachers convey advanced electromagnetic concepts with well-known applications in wireless communications.
Figure 6 shows a computer-aided design (CAD) model
of an actual urban environment. Using electromagnetic ray tracing software developed through collaboration between Drexel University and Universidad de Alcala in Spain, high school teachers from the Philadelphia area will be able to explore various concepts in wireless communications and signal processing. Using these advanced calculations and desktop virtual reality techniques relying on the Virtual Reality Markup Language (VRML), teachers will be able to simulate various scenarios and develop web-based demonstrations that can enhance their students understanding of electromagnetics.
The tools developed at Drexel University can be used to explore many different aspects of wireless communication signal propagation that are relevant to the study of cellular communications and ad-hoc wireless local area networks. Figure 7a shows a screenshot of a web-based animation of how multipath signal energy takes different paths when traveling from transmitter (basestation) to receiver (mobile user) as the user moves through the streets of the urban environment. Figure 7b shows how the power distribution over the same urban area can be measured and viewed at a large scale.
In order to achieve the primary goal of developing web-based high school instruction material, teachers will work with Dr. Kapil Dandekar to conduct research into electromagnetic signal propagation and its application in wireless communications systems. After conducting this research, the teachers will work with the Drexel Wireless Systems Laboratory to design, simulate, and visualize various configurations of wireless users moving through computer models corresponding to dense urban regions of Center City, Philadelphia. The class materials developed by the teachers through this effort will provide unique insights to high school physics students who would not otherwise have access to these computational tools.
3) Human-Computer Interaction - (Dr. Paul Oh)
Cameras are often mounted on motion platforms like aircraft, rovers, submersibles, and broadcast equipment to visually monitor scenes (See Figure 8). Oftentimes a platform is teleoperated – to obtain desired views the human operator, via remote control, simultaneously maneuvers the platform and aims the camera. Such multitasking demands a highly trained person who avoids crashing the platform and losing camera focus.
Performance in important applications like surveillance, situation assessment, exploration, site inspection, and live event coverage are limited to operator skill and experience. What is needed is a method to augment an operator’s performance for such applications. Towards addressing this need, human-computer interaction is a candidate emerging technology. Our particular focus is to enable a person and computer to share control over the platform and camera; the operator concentrates on safely navigating the platform while computer vision automatically keeps the target in focus. The pedagogy of robot/mechatronic design, computer vision/graphics, embedded microprocessors and sensor-fusion underlying our focus will bring Philadelphia school district K-12 teachers up to speed with this emerging technology.
The partnership between high school teachers and Dr. Oh will result in web-based materials that instruct high school students on robot design and construction. The partnership will research human-computer interaction where a person remotely controls a robot. The specific aim identifies sensors that improve control especially when the person cannot physically see the robot. Completing this research, a robot racing competition will be held; teacher teams construct a working robot and equip it with sensors they identified to be important. Teachers will keep engineering journals documenting their hands-on experiences. These will be written into web-based tutorials for far-reaching impact; high school students are provided robot-building lessons that exercise skills in problem solving, mechanism design, electronic circuitry and programming. Our prior relationships with teachers and industries in U.S. FIRST (a national K-12 robotics competition) suggest the interaction will be successful.
4) Internet Economics - (Dr. Harish Sethu)
Since the transformation of the Internet over the last decade into a commercial infrastructure, its evolution has been and will likely continue to be driven by an interplay of a variety of technical, economic and social considerations. As one example of this interplay, economic incentives have emerged as a practical tool toward achieving certain difficult engineering goals. With the Internet serving as a shared resource for a very large number of users with competing interests, this point has been most persuasively argued by researchers who propose pricing as a means to achieve congestion control and differentiated quality of service (QoS). This research seeks to make novel contributions in the use of economic incentives to serve a significantly more diverse set of engineering goals and beyond the traditional goals of congestion control and QoS. Our goal is to explore the hypothesis that targeted economic incentives may be employed to achieve improved engineering efficiency in a variety of policies and mechanisms that govern scheduling, routing, security, web caching and replication, and the topological or architectural design of content distribution networks and overlay networks. In contrast to most of the past research on using economic theories in engineering, this work will pay close attention to the feasibility of actual deployment of proposed solutions by considering security and scalability issues in the algorithmic aspects of the solution as well as in the supporting infrastructure for billing and accounting. In the following, we describe one of many examples of the potential for improved engineering efficiency through pricing.
The Internet is organized in a hierarchical fashion with a large number of interconnected Autonomous Systems (ASes), each of which is operated independently by an organization such as a corporation, a university or an Internet Service Provider. In the core of the Internet, exchange of routing information between ASes is accomplished through the Border Gateway Protocol (BGP), a path vector routing protocol. It is possible that ASes will use conflicting policies leading to route divergence. That is, a set of policies implemented by ASes could be such that they continually exchange BGP routing messages but never converge on a set of stable routing paths. This instability can cause packet losses, or lead to packets being delivered out of order, and thus reduce the end-to-end throughput and delay performance. Some instances of heavy routing instability may even lead to a loss of connectivity. Such ``route flap storms'' are quite common and have frequently resulted in extended outages for millions of Internet users. In addition, BGP policies cause sub-optimal routing in the Internet with about half the source-destination pairs using a larger number of hops than necessary. Pricing holds the promise of a significantly more efficient alternative through eliminating much of the need for policy-based routing between ASes, providing an incentive for ASes to carry transit traffic, and ultimately improving the utility of the Internet infrastructure for consumers. In this research, we will seek to use formal measures of actual economic costs incurred in the use of network resources and develop dynamic algorithms that incorporate these costs into automated service level agreements and capacity planning strategies. Additionally, these algorithms will allow one to appropriately re-engineer routing protocols based on game-theoretic and other economic models to take these costs into account, potentially leading to significantly improved routing efficiencies. An important component of our methodology is based on adding security to our pricing framework through the use of some of the recent advances in financial cryptography. Further, the scale-free nature of the Internet topology, a small section of which is shown in Figure 1, imposes unique and interesting routing behaviors that will be investigated as part of this project.
