Recently ABLAZE built a stewart platform in the lab to test out a cool advanced technology concept for discharging wheeled/tracked vehicles at-sea. Once we had the platform physically built and six actuators wired for input, we looked into what types of sensor systems we could quickly assemble that was within our budget. After some research, we decided that the best solution at this stage of our prototype was a Wii remote (or more commonly referred to as a Wiimote). Yes, you read that correctly a Wiimote! A Wiimote is actually a very sophisticated wireless sensor system that includes an IR filtered camera sensor with built-in image processing capable of tracking up to four moving objects and an accelerometer which measures linear acceleration on 3-axises: side to side (X), front and back (Y) and up and down (Z). At less then $15 a device and an open source interface library that is widely available on Ubuntu, how could we not give it a go? So now that the basic sensor system is defined, we then needed to design a way to programmically control the six actuators of the platform with the sensor information that would be collected wirelessly by the host software. For the control system, we decided on using a popular open source microcontroller prototyping board designed in Italy, called Arduino which lists for under $60. The Arduino has an 8-bit RISC-based microcontroller with on-board input/output (I/O) support that includes digital, analog and pulse-width modulated I/O pins. The board is typically programmed using a Wiring-based language that is similar to C. After a few weeks of software development we had the platform automatically moving based on the positioning of an IR LED array target, which by the way was a $5 replacement Wii sensor bar.
Adobe AIR, a component of the Adobe Flex Platform, enables developers to deliver a consistent looking mobile application across multiple devices and platforms using a single code base. Developers no longer have to decide which native development SDK will they need to invest their time and effort in – whether iOS and Objective-C or Android and Java. AIR mobile apps can be developed writing ActionScript code, a language similar to Java, using Adobe’s Flex Builder, an Eclipse based IDE or by downloading the free Adobe AIR SDK. Besides cross device mobile apps, the Adobe AIR development framework also enables developers the ability to not only deliver consistent cross browser Rich Internet Applications (RIA) but deploy cross platform desktop applications running either OSX, Windows or Linux. Adobe AIR mobile apps can easily be uploaded to the Apple Store, Android Market, Blackberry App World, Amazon AppStore or Adobe Marketplace for distribution.
Note that earlier this month there were two key releases provided by Adobe, Adobe Flex Builder version 4.5.1 : now supports automatically packaging the application to Android, iOS and Blackberry Playbook; and Adobe AIR version 2.7 : which provides Blackberry Playbook support and includes enhanced iOS performance rendering and debugging workflow.
The Semantic Web allows users to interpret the meaning of data and business processes because of explicit semantics provided with the information, which develops a capability of knowledge discovery and re-usability. Jena is a Java-based Semantic Web framework initially developed by HP Labs and now supported by the Open-Source Community.
The Jena framework provides Semantic Web technologies such as Resource Description Framework (RDF), RDF Schema, Web Ontology Language (OWL) and SPARQL. RDF provides the ability to decompose knowledge into small, structured pieces of data, with rules about the meaning of those pieces of data. OWL is the W3C’s recommended ontology language for representing information in the Semantic Web. SPARQL is a SQL-like language for querying RDF models. The Jena framework is designed to allow a range of pluggable rule-based inference engines, otherwise referred to as reasoners. Given an ontology and a RDF model, Jena’s inference engine can derive additional statements that the model doesn’t express explicitly. This is a powerful capability which allows for the discovery of new relationships.
This month we are evaluating a open source Linux-based computer-on-module (COM) from Gumstix, Inc for use in future applications. The Overo Air module comes with an OMAP 3503 ARM Cortex-A8 600 MHz CPU, W2CBW003 System-in-Package (SiP) that provides 802.11g and Bluetooth wireless connectivity, an on-board microSD card slot and is pre-flashed with Linux 2.6.29, Ångström distribution.
Gumstix Overo Air on Summit Board