Remote Monitoring of Barowell Pumps Using a Radio Link

Barowell pumps are notorious for having problems and failures, which sometimes occur at the most inopportune times during aeropropulson testing. These failures could be better predicted with proper health monitoring. Continuous monitoring of changes in the health of the pump would allow timely preventive and corrective maintenance to be performed as necessary to reduce failures and reduce plant downtime. This thesis addresses a wireless method to monitor these pumps remotely by a user located in the control room. The operator can note the ultrasonic amplitude of the bearings on the pumps and make a decision to schedule preventive maintenance. An UE Ultra-Trak 750 ultrasonic microphone was used to produce the analog data. Its output was put through an anti-alias filter and then digitized. An Analog Devices ADuC 7024 microcontroller was used to sample and digitize the data. Digital data was then sent out over the UART to a MaxStream 9XTend RF Module. This module sent the data over a radio link where it was received and processed using the Computer Assisted Dynamic Data Monitoring and Analysis System (CADDMAS) at AEDC. The design and development of this system is described in detail herein. The system was designed with a two-channel capacity. The system used a 4 kHz multiplexed A/D to obtain a 2 kHz sample rate per channel and the data was sent out at baud rate of 115200 via a 900 MHz serial RF modem. After development, the system performed the desired function of transmitting the ultrasonic vibration data to the user for evaluation. Data was reliably transmitted at 10mW over the air to a host computer located approximately 120 ft where it was successfully processed

Space Shuttle/TDRSS communication and tracking systems analysis

In order to evaluate the technical and operational problem areas and provide a recommendation, the enhancements to the Tracking and Data Delay Satellite System (TDRSS) and Shuttle must be evaluated through simulation and analysis. These enhancement techniques must first be characterized, then modeled mathematically, and finally updated into LinCsim (analytical simulation package). The LinCsim package can then be used as an evaluation tool. Three areas of potential enhancements were identified: shuttle payload accommodations, TDRSS SSA and KSA services, and shuttle tracking system and navigation sensors. Recommendations for each area were discussed

Media Transport and Use of RTP in WebRTC

The framework for Web Real-Time Communication (WebRTC) provides support for direct interactive rich communication using audio, video, text, collaboration, games, etc. between two peers' web browsers. This memo describes the media transport aspects of the WebRTC framework. It specifies how the Real-time Transport Protocol (RTP) is used in the WebRTC context and gives requirements for which RTP features, profiles, and extensions need to be supported

Real-time Audio-Visual Media Transport over QUIC

We consider the problem of how to transport low-latency, interactive, real-time traffic over QUIC. This is needed to support applications like WebRTC, but difficult to support due to the reliable, unframed, nature of QUIC streams. We review the needs of low-latency real-time applications and how they have been supported in previous protocols, then propose a minimal set of extensions to QUIC to provide such support. Compared to a raw datagram service, our extensions provide meaningful support for partially reliable and real-time flows, in a backwards compatible manner

Voice and Video Capacity of a Secure Wireless System

Improving the security and availability of secure wireless multimedia systems is the purpose of this thesis. Specifically, this thesis answered research questions about the capacity of wireless multimedia systems and how three variables relate to this capacity. The effects of securing the voice signal, real-time traffic originating foreign to a wireless local area network and use of an audio-only signal compared with a combined signal were all studied. The research questions were answered through a comprehensive literature review in addition to an experiment which had thirty-six subjects using a secure wireless multimedia system which was developed as part of this thesis effort. Additionally, questions related to the techniques for deploying wireless multimedia system including the maturity and security of the technology were answered. The research identified weaknesses in existing analytical and computer models and the need for a concise and realistic model of wireless multimedia systems. The culmination of this effort was the integration of an audio-video system with an existing research platform which is actively collecting data for the Logistics Readiness Branch of the Air Force Research Laboratory

Out-of-band transfer with Android to configure pre-shared secrets into sensor nodes

Applications based on Wireless Sensor Networks are making their way into all kinds of industries. Today, they can do anything from off-loading hospitals by monitoring patients in their homes to regulating production lines in factories. More often than not, they perform some kind of surveillance and tracking. Thus, in most cases the information they carry is sensitive, rendering good encryption schemes suited for performance-constrained sensor nodes a valuable commodity. As traditional encryption is not well suited for performance constrained environments, there are many new "lightweight" encryption schemes emerging. However, many of the popular up and coming schemes make the assumption of already having a pre-shared secret available in the sensor node beforehand which can act as the base for their encryption key. The procedure of configuring this pre-shared secret into the sensor node is crucial and has the potential of breaking any scheme based on that assumption. Therefore, we have looked at different procedures of configuring this pre-shared secret into a sensor node securely, using nothing more than a smartphone to configure the sensor node. This would eventually eliminate the assumption of how the pre-shared secret got into the sensor node in the first place. We used an Arduino Uno R3 running an Atmega328p MCU as a simulation of a potential sensor node. Moreover, using a smartphone as the configuration device, we chose to base the communication on two types of OOB based side-channels; Namely, a visual-based using the flashlight and screen as well as audio-based, using the loudspeaker. We concluded that using a smartphone as configuration device has its difficulties, although, in this specific environment it is still a viable choice. The solution can decrease the previous knowledge required by the user performing the configuration while simultaneously upholding a high security level. The findings of this thesis highlight the fact that: technology has evolved to a point where the smartphones of today can outperform the specialized devices of yesterday. In other words, solutions previously requiring specialized hardware can today be achieved with much less "specialized" equipment. This is desirable because with less specialized equipment, it becomes easier to further develop and improve a system like this, increasing its viability.Have you ever wondered what would happen if somebody could access your refrigerator? Might seem silly, but how about your front door's lock? With the ever increasing connected society, you might have to think about these questions sooner rather than later. The establishment of our connected society is heavily dependent on sensor nodes. There is currently no rigid way of loading the necessary cryptographic keys into these sensor nodes. Now, to enable these sensor nodes to communicate securely, we have studied alternative ways of using your smartphone to transmit these keys to the sensor nodes. In this thesis, we have shown alternative ways of using a smartphone to transmit cryptographic keys into sensor nodes. These alternative ways were achieved by using components not otherwise thought to be used for communication. For instance, we built prototypes that used the flashlight; the screen and the loudspeaker to successfully transmit the keys. Doing this we were able to make the transmission easy to use while at the same time upholding a high level of security. Currently, the sensor nodes have many protocols available to use for secure communications. However, these protocols often lack information about how one should load the sensor nodes with the keys, to begin with. In essence, they provide you with the car but not the key to start it. This is a problem that needs a concrete solution. The result of this thesis can be used as a guideline for further development of this type of solution. Our prototypes indicate that this type of solution is not only viable but can be secure as well. Using nothing more than a smartphone and small additions to the sensor nodes hardware. Briefly, the prototypes are built using an Android-powered smartphone as "key-transmitting device" while the receiving "sensor node" is equipped with a microphone or a photo-transistor. The additions to the receiver enable detection of both light and sound waves sent from the smartphone. Then, using the smartphone, the user is able to transmit data by blinking with the flashlight or screen; or sending tones with the loudspeaker, which the receiver interprets