Mesh Protection
Curriculum Links
Understanding The Nature of Technology Strand:
Characteristics of Technological Outcomes
Technological outcomes are defined as fully realised products and systems, created by people for an identified purpose through technological practice. Within this definition, technological outcomes can be categorised into two types – technological products and technological systems. For discussion of this topic, see www.techlink.org.nz/curriculum-support/papers/nature/char-tech-out/page2.htm
Focus questions
System or Product?
Christchurch based electrical engineer Dave Rankin, has developed an innovative system to monitor horticultural crops using a wireless mesh network that delivers climatic information to growers using a robust and simple technology.
"After a fair bit of development of hardware and software, I came up with a product that collects information in real time for vineyards," says Dr Rankin.
Here the outcome produced is described as both a system and a product.
Task
Discuss how the outcome produced could equally well be categorised either as a system or as a product.
Designing a wireless mesh network
Reference: www.indigosystems.net.nz
A wireless mesh network is a series of radio transmitting devices arranged so that each of the nodes can communicate with any other node – rather than just back to the central receiver.
In self-configuring networks, like the Indigo network, nodes look around for their nearest neighbours and automatically establish links with them. This makes the network very reliable because if one node falls out, or is removed, the network searches for alternative routes to keep the communication path alive.
Mesh networks use a lot less power than traditional transmitters – only enough power is required to transmit to the nearest node, rather than to a central receiver. The nodes spend most of the time asleep and wake only to transmit packets of data. These features make for a vastly extended battery life.
These networks can transmit any kind of environmental data – if a physical quantity can be measured with a sensor, then it can be connected to an Indigo node and beamed back to the data collection point.
Nodes can receive as well as transmit so networks can be used to both monitor and control the environment.
Task:
Develop a conceptual design showing inputs outputs and transformations for a system to maintain soil moisture levels on a hill country vineyard.
Other references to intelligent sensors and wire mesh networks
Remote sensors and their applications
For a long time, environmental scientists have braved extreme conditions – high altitudes, rough seas, steep terrain, isolation, rain, snow and wild animals – to gather the data they need to understand natural phenomena. They may need less bravery in the future: wireless sensor networks (WSNs) are taking some of the adversity out of their jobs and simultaneously sparking rapid advances in environmental science. Read Nova Science in the News article: www.science.org.au/nova/097/097box02.htm.
Smart sensors and the environment
How do you manage a unique natural resource like the Great Barrier Reef when it's threatened on so many fronts? Read Nova Science in the News article: www.science.org.au/nova/110/110key.htm.
