TCR update

Building The Clashing Rocks prototype was fun. It really identified some brick wall challenges surrounding the quantity of data we had to process in real-time. Even encoding to bit-level was not going to cut it. As a result a new direction for the project will be to focus solely on recording the seismic events. This will provide more opportunity to implement techniques to work with the bandwidth constraints in place and will eliminate the hard real-time processing constraints. There will still be the challenge of synchronising, logging and presenting the data but we will focus more on providing high-level APIs and/or a DSL to help realise this. The project will still be OpenWrt based and run on different architectures.

The Clashing Rocks

This project is about using embedded Linux devices to detect, record and react to seismic events. The idea is to use accelerometers to detect shaking and then communicate this event to all other devices connected to the same broadcast group. We are developing the technology using OpenWrt which allows us to use a range of hardware including routers and pocket computing devices. We really like the idea of exploring emerging low-powered, low-bandwidth mesh networks in developing countries. In this video you can see some early work using a network of Ben NanoNote computers fitted with WPAN hardware. Three devices are connected to a Spread daemon running on a co-ordinating device. Because our current hardware lacks accelerometers we run a program on one device to send fake accelerometer data onto the network. Each device should then pick up this data across our wireless network. We are currently able to get some basic support for IP networking using a hack by Werner Almesberger who also developed the WPAN hardware.  In the video you can see the devices display a bar graph indicating it received data. Only one bar is registered as only one device is transmitting. This bar graph could act as a finger print for deciding the scale of seismic activity in a larger network. We intend to add some more intelligence to this part by building a some kind of knowledge system. Currently the project is at a very early stage with some basic infrastructure developed in C. The aim is to extend this infrastructure by embedding GNU Guile. This will allow us to dynamically control how we communicate, store and process the structured data shared amongst devices. Part of this system will involve trying to minimise the quantity of structured data exchanged on the network by serialising to bit-level using Packedobjects.

Further details of the project can be found at The Clashing Rocks wiki.