Performance simulation of HIPERLAN/2 with low debit traffic for real time data acquisition and control applications

Wireless local area networks can be suitable for remote interconnection of different data acquisition and control systems over a standardized telecommunications network, using several communication technologies, such as ISDN, ATM or IP. This paper presents an overview of the HIPERLAN/2 specifications as well as simulation results of this system, with channel errors and mixed traffic generated by control applications

Development and Flight Testing of a Wireless Avionics Network Based on the IEEE 802.11 Protocols

This report describes the development and flight testing of the IEEE 802.11 protocol-based Wireless Flight Management System (WFMS) using low cost Commercial-Off-The-Shelf (COTS) equipment and software. The unlicensed spectrum allocation in the 2.4 GHz and 5 GHz bands by the FCC has encouraged the industry to develop new standards for short-range communication that are commercially viable. This has resulted in new short-range communication technologies like Bluetooth and the Wireless Local Area Network (WLAN). The new modulation techniques developed for wireless communication support wired equivalent data rates. The commercial success of these technologies and their wide market adaptation has resulted in reduced costs for the devices that support these technologies. Applications of wireless technology in aerospace engineering are vast, including development, testing, manufacturing, prognostics health management, ground support equipment and active control. The high data rates offered by technologies like WLAN (IEEE 802.11 a/b/g) are sufficient to implement critical and essential data applications of avionics systems. A wireless avionics network based on IEEE 802.11a/b/g protocols will reduce the complexity and cost of installation and maintenance of the avionics system when compared to the existing wired system. The proposed WFMS imitates the flight management system of any commercial aircraft in terms of functionality. It utilizes a radio frequency for the transmission of the sensor data to the Cockpit Display Unit (CDU) and the Flight Management Computer (FMC). WFMS consists of a FMC, data acquisition node, sensor node and a user interface node. The FMC and the data acquisition nodes are built using PC/104 standard modules. The sensor node consists of an Attitude and Heading Reference System (AHRS) and a GPS integrated with a serial device server. The user interface node is installed with moving map software which receives data from the AHRS and GPS to display flight information including topographic maps, attitude, heading, velocity, et cetera. This thesis demonstrates the performance evaluation of the WFMS both on the ground and in flight, and its advantages over a wired system. This thesis focuses on the evaluation of IEEE 802.11a/b/g protocols for avionics application. Efforts taken to calibrate the available bandwidth of the WLAN network at different operating conditions and varying ranges using different network analysis tools are explained briefly. Considerable research on issues like electromagnetic interference and network security critical to the development of a wireless network for avionics has also been done. This report covers different aspects of the implementation of wireless technology for aircraft systems. This work is a successful starting point for the new fly-by-wireless concept with extensions to active wireless flight control

Analysis, simulation and testing of ITS applications based on wireless communication technologies

Intelligent Transportation Systems (ITS) aim to improve road transport safety and efficiency, to manage road networks in the interest of the society and to provide real time responses to events. In order to reach these goals, real time feedback to the drivers is expected through the integration of telecommunications, sensing and information technologies with transport engineering. Wireless communication technologies, that have been used in industrial applications for more than 30 years, play a crucial role in ITS, as based on the concept of multiple devices (on both vehicle and infrastructure side) interconnected in different ways. Connectivity, in tandem with sensing technologies, is fuelling the innovations that will inevitably lead to the next big opportunity for road transport: autonomous vehicles. Therefore, this study has investigated - through analysis, simulation and field testing – on applications based on wireless communication technologies meant to support both Data acquisition and Data diffusion as fundamental aspects/ phases in ITS, where data is widely individuated as being the key element

Development of high-precision distributed wireless microseismic acquisition stations

In recent years, owing to the shortage of oil and gas resources and increasing difficulty in mining, traditional (wired) microseismic monitoring equipment has been unable to meet the needs of energy exploitation. Therefore, it is necessary to develop new high-precision seismic exploration and data acquisition systems. In this study, we combined advanced acquisition systems with wireless technology to develop a new wireless microseismic acquisition system. The hardware circuit of the acquisition system mainly includes a data acquisition board and a main control board. High-precision analog-to-digital conversion and digital filtering technologies are used to provide data with high signal-to-noise ratios, resolution, and fidelity to the acquisition stations. Key technologies were integrated into the ARM (Advanced RISC Machines) of the main control board: reliable GPS technology was employed to realize synchronous acquisitions among various acquisition stations, and WIFI technology was used to achieve wireless data communication between acquisition stations and the central station, thus improving the data transmission speed and accuracy. After conducting a series of evaluation tests, it was found that the system was stable, convenient to use, and had high data accuracy, therefore providing significant support for the solution to problems encountered in current oil and gas exploration processes, such as the complicated environment and inconvenient construction.</p

Handcrafted Microwire Regenerative Peripheral Nerve Interfaces with Wireless Neural Recording and Stimulation Capabilities

A scalable microwire peripheral nerve interface was developed, which interacted with regenerated peripheral nerves in microchannel scaffolds. Neural interface technologies are envisioned to facilitate direct connections between the nervous system and external technologies such as limb prosthetics or data acquisition systems for further processing. Presented here is an animal study using a handcrafted microwire regenerative peripheral nerve interface, a novel neural interface device for communicating with peripheral nerves. The neural interface studies using animal models are crucial in the evaluation of efficacy and safety of implantable medical devices before their use in clinical studies. 16- electrode microwire microchannel scaffolds were developed for both peripheral nerve regeneration and peripheral nerve interfacing. The microchannels were used for nerve regeneration pathways as a scaffolding material and the embedded microwires were used as a recording electrode to capture neural signals from the regenerated peripheral nerves. Wireless stimulation and recording capabilities were also incorporated to the developed peripheral nerve interface which gave the freedom of the complex experimental setting of wired data acquisition systems and minimized the potential infection of the animals from the wire connections. A commercially available wireless recording system was efficiently adopted to the peripheral nerve interface. The 32-channel wireless recording system covered 16-electrode microwires in the peripheral nerve interface, two cuff electrodes, and two electromyography electrodes. The 2-channel wireless stimulation system was connected to a cuff electrode on the sciatic nerve branch and was used to make evoked signals which went through the regenerated peripheral nerves and were captured by the wireless recording system at a different location. The successful wireless communication was demonstrated in the result section and the future goals of a wireless neural interface for chronic implants and clinical trials were discussed together

The Challenges of Integrating Instrumentation with Inflatable Aerodynamic Decelerators

To realize the National Aeronautics and Space Administration s (NASA) goal of landing humans on Mars, development of technologies to facilitate the landing of heavy payloads are being explored. Current entry, decent, and landing technologies are not practical when utilizing these heavy payloads due to mass and volume constraints dictated by limitations imposed by current launch vehicle fairings. Therefore, past and present technologies are now being considered to provide a mass and volume efficient solution, including Inflatable Aerodynamic Decelerators (IADs) [1]. IAD ground and flight tests are currently being conducted to develop and characterize their performance under flight-like conditions. The integrated instrumentation systems, which are key to the performance characterization in each of these tests, have proven to be a challenge compared to the instrumentation of traditional rigid aeroshells. To overcome these challenges, flexible and embedded sensing systems have been developed, along with improved instrumenting techniques. This development opportunity faces many difficult aspects specific to inflatable structures in extreme environments. These include but are not limited to: physical flexibility, packaging, temperature, structural integration and data acquisition [2]. To better define the instrumentation challenges posed by IAD technology development, a survey was conducted to identify valuable measurements for ground and flight testing. From this survey many sensing technologies were explored, resulting in a down-selection to the most viable prospects. These systems were then iterated upon in design to determine the best integration techniques specific to a 3m and 6m stacked torus IAD. Each sensing system was then integrated and employed to support the IAD testing in the National Full-Scale Aerodynamics Complex 40 x 80 wind tunnel at NASA Ames Research Center in the summer of 2012. Another challenge that has been explored is the data acquisition of IAD sensing technologies. Traditionally all space based sensing systems transmit their data through a wired interface. This limits the amount of sensors able to be integrated within the IAD due to volume and routing restrictions of the supporting signal and excitation wires. To alleviate this situation, multiple wireless data acquisition technologies have been researched and developed through rapid prototyping efforts. The final custom multi-nodal wireless system utilized during the summer 2012 IAD test series consisted of four remote nodes and one receiving base station. The system reliably conditioned and acquired 20+ sensors over the course of the wind tunnel test series. These developments in wireless data acquisition techniques can eliminate the need for structural feedthroughs and reduce system mass associated with wiring and wire harnesses. This makes the utilization of flight instrumentation more attractive to future missions, which would result in further improved characterization of IAD technology, and overall, increased scientific knowledge regarding the response of inflatable structures to extreme entry environments.

Microwire regenerative peripheral nerve interfaces with wireless recording and stimulation capabilities

A scalable microwire peripheral nerve interface was developed, which interacted with regenerated peripheral nerves in microchannel scaffolds. Neural interface technologies are envisioned to facilitate direct connections between the nervous system and external technologies such as limb prosthetics or data acquisition systems for further processing. Presented here is an animal study using a handcrafted microwire regenerative peripheral nerve interface, a novel neural interface device for communicating with peripheral nerves. The neural interface studies using animal models are crucial in the evaluation of efficacy and safety of implantable medical devices before their use in clinical studies.16-electrode microwire microchannel scaffolds were developed for both peripheral nerve regeneration and peripheral nerve interfacing. The microchannels were used for nerve regeneration pathways as a scaffolding material and the embedded microwires were used as a recording electrode to capture neural signals from the regenerated peripheral nerves. Wireless stimulation and recording capabilities were also incorporated to the developed peripheral nerve interface which gave the freedom of the complex experimental setting of wired data acquisition systems and minimized the potential infection of the animals from the wire connections

SCADA and related technologies

Presented at SCADA and related technologies for irrigation district modernization: a USCID water management conference on October 26-29, 2005 in Vancouver, Washington.The Zigbee™ alliance seeks to develop an open standard for reliable, cost-effective, secure wireless interconnectivity of monitoring and control products. The ZigBee™ technology is better suited for control applications, which do not require high data rates, but must have low power, low costs and ease of use. In this paper we investigate the applicability of Zigbee™ to Supervisory Control and Data Acquisition (SCADA) systems an investigate issues relating to: Networking, Security, Reliability and Quality of Service