Version 1.0 of LiteOS has just been released. Now offering complete support for Crossbow's popular IRIS Mote platform, several new features have been implemented. Key Features in Version 1.0 include:
Windows XP, Windows Vista and Linux Support
Support for MICAz and IRIS nodes
Plug-and play routing stack
Extremely lightweight event logging
Unix like commands to operate the entire sensor network
Multi-threading kernel
Write applications in C
Native wireless reprogramming
Built-in hierarchical file system
Extensive development libraries
Java tools to display and visualize data
Online debugging support, including variable watches and unlimited number of breakpoints
Elastic dynamic memory that has almost zero overhead
Snapshot a thread state or restore it to a previous state
Installer for quickly deploying the LiteOS operating system
Documentation to quickly get started with operating and programming
The goal of LiteOS is to simplify sensor network programming. For more information on this OS, click here.
What forces drive us and keep us going? What energy do we need to power us on? Energy is often defined as the ability to do work or to cause change. Power is defined as the rate of doing work or the rate of using energy. Energy has
always existed in one form or another, and sometimes in places we often overlook. While the world has focused on using radio waves for communication,
Powercast has focused on capturing radio waves to power devices.
Founded in 2003, Powercast developed an RF energy harvesting module with
breakthrough efficiency levels. Coupled with a transmitter that sends
RF energy using algorithms developed by Powercast, the Powercast
Wireless Power Platform™ was born. While the concept of sending power
“through the air” has been discussed for more than 100 years, Powercast
is the first company to make it commercially viable and harness energy in this form.
A Powercaster™ transmitter chip, running on conventional 110V pwer,
broadcasts a low-power radio (RF) signal at a specific frequency across inches or tens of meters of free space. Powerharvester™ receivers built into
one or more remote devices capture enough energy to continuously
recharge batteries, or to power devices directly. Patented algorithms more than double the effective range of
conventional RF power output. A patented receiver circuit design captures up to
70% of the theoretical maximum anywhere within the Powercaster’s range.
Powercast technology is designed for low power applications such as Crossbow's Mote platforms. Any device that uses a small battery (e.g. AAA,
AA, coin cell, thin-film) or capacitors and and can be placed near a transmitter either continuously
or even occasionally is a viable candidate. The radio energy received by the RF Powerharvester allows devices to be recharged even when not plugged into or docked with a charger.
During a recent visit to Crossbow Technology, Powercast representatives Charlie Greene (Chief Scientist) and Harry Ostaffe (Director of Marketing) demonstrated how Crossbow's popular IRIS Mote platform benefits from this type of power source (operating the IRIS Mote without batteries using RF energy at 900MHz). With its low power, low data rate design, the IRIS Mote is a perfect candidate for Powercast RF energy harvesting technology to harness the power sent via radio energy to extend its battery life through wireless recharging, essentially providing perpetual, lifetime power.
Powercast believes that repeated battery replacements is a major impediment to enabling wireless sensor networks to scale to hundreds or thousands of nodes and view their wireless power technology as the solution. Powercast is now leading the cross-industry initiative to bring wireless power to a hundreds of low power devices including wireless sensors. Powercast's FCC approved technology has been supplying commercial products within
the United States since the end of
2007.
Powercast is dedicated to provide RF energy harvesting and wireless power solutions that deliver milliWatts over tens of meters, Watts over centimeters. In comparison to other alternative
energy technologies, Powercast accomplishes power transmission in a
unique manner.Unlike pure ambient energy harvesting technologies like Piezo, solar or kinetic power, Powercast technology can be “always on”, or used in an on-demand or scheduled manner. Additionally, Powercast has the ability to deliver power through walls, ceilings and surfaces (rubber, plastic, plaster and wood).
The .NET Micro Framework is a platform that enables developers to more
quickly develop embedded systems that are smart, securely connected and
easier to manage. Jonathan Kagle, Microsoft's .NET Micro Framework
Senior Program Manager, introduces some of the hardware
developers are using in Micro Framework devices, including Crossbow's Imote2.Net Edition wireless sensor node platform on Engineering TV.
The Imote2.NET Edition (IPR2410) is built around the low-power PXA271 XScale processor and
integrates an 802.15.4 radio (CC2420) with a built-in 2.4GHz
antenna. The Imote2 IPR2410 is factory configured to run .NET
Micro Framework. It is also sold as part of the Imote2.Builder
kit.The Imote2.NET Edition is a modular stackable platform and can
be expanded with extension boards to customize the system to a specific
application. Through the extension board connectors sensor boards can
provide specific analog or digital interfaces. A battery board is
provided to supply system power, or it can be powered via the
integrated USB interface.
These magical words won't take you to a cave of treasures, but they do lead us to some exciting applications for wireless sensor networks that open up a treasure trove of information previously inaccessible. SESAME: SEnsing for Sport and Managed Exercise has a vision in which athletes and coaches are continuously provided with precise and relevant information about their performance, their body state and posture, presented in a form determined by sport-specific training requirements based on a careful analysis of coaching methods and coaches’ informational needs. To realize this, athletes wear an easily-extensible range of different sensors that capture accurate information about their position, skeletal posture, muscular response, and physiology in a way that is non-intrusive and capable of working in the context in which the athlete normally performs. This setup is engineered so as not to cause injury, discomfort or performance degradation and it must not interfere with aerodynamics. Wearable sensors are complemented by track-side monitors and video capture equipment and by an integrated hardware/software/network platform designed to enable substantial volumes of data to be gathered, recorded, analyzed and presented to athletes and coaches in the most accessible and useful form. The main objective of the SESAME project is to conduct high-quality scientific research to produce deployable systems that have a positive and measurable impact on the training of elite athletes.
Researchers at the University of Cambridge have just released an open source low power 802.11 sensor board tailored for Crossbow's Imote2 platform. The SESAME consortium is a multidisciplinary group consisting of 6 partners with University of Cambridge Engineering Department as a member. The sensor board developed is designed to support the high data rate requirements of the sports sensing application. The UCAM-WSB100 is a low power wireless sensor daughter board for the Imote2 platform designed to facilitate high data-rate wireless sensor applications. Developed to support the SESAME project, the board will be used to collect real-time and off-line processing and feedback in enhancing the performance of elite athletes.
Overview of the UCAM-WSB100 sensor board: * Compatible with the Imote2 processor board * Low Power 802.11 b/g based on Marvell 88W8686 chipset * Supports ad-hoc and infrastructure modes * Access to power control of the radio system * 12 analog channels (12-bits resolution) * Physical dimensions: 48mm x 36mm *
Linux driver support via libertas drivers in mainline kernel
The information obtained from the sensors will be pre-processed on the athlete to take account of the measurements required and the prevailing network conditions. The data is then transmitted wirelessly to a base-station and application platform. Here, the data will be further fused and processed in a way that is informed by an understanding of biomechanical models of athletes; an understanding of the consequences of sensor placement error and physical properties of the method of attachment; and the coaching objective for which the data are being captured. Within SESAME, the primary experimental focus will be on sprinting, for which precise technique is hugely important and mechanical constraints on performance are well understood. Consequently, the derived data will include the position, velocity, acceleration and orientation of the athlete, their stride length and rate, body posture and instantaneous pressure in the shoes, as well as physiological data such as heart rate and blood oxygen level. The data will then be output in three different ways: they will be sent for long term storage and offline analysis; they will be presented visually to the coaches in a way that is meaningful to them; and they will be returned directly to the athlete in real time as biofeedback.
The UCAM-WSB100 is created as an open source platform. As part of the effort to develop open source hardware for use in conjunction with Crossbow's Imote2, the details of the hardware reference design (schematics, board layout diagrams) are available to the wireless sensor network community. Users will be able to easily tailor the system to their particular application. Researchers at the University
of Cambridge are seeking volunteers to help improve the hardware reference design and add support for this board in other operating systems such as TinyOS and .Net. If interested in participating in this development, click here and for more information on this project, click here.
