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.
The name of the project derives from Greek mythology. The Clashing Rocks or Symplegades were a pair of rocks at the upper end of the Bosphorus at the point where the strait enters the Black Sea. These rocks would clash randomly and prove hazardous to sailors who tried to pass them. This project is about using pervasive technology to help detect and share knowledge of such random behaviour.