Wireless sensors simplify machine monitoring

Engineers working for the Rockwell Science Center - Rockwell`s corporate research organisation - have developed a wireless sensor monitoring system that, they say, will simplify industrial monitoring installations. The HiDRA (Highly Deployable Remote Access) system uses a network of intelligent nodes to gather and analyse data from machines, and to transmit this information to local and remote users.

Each node accepts inputs from up to five sensors, measuring variables such a vibration or temperature. The nodes, measuring 15.2 x 8.9 x 7.6 cm, are designed to be mounted on machines.

The nodes contain a processor to convert the raw data into high-value information, and a low-power radio to transmit the data over distances of up to 100m. Rockwell says that the 2.4GHz signals will penetrate walls and floors.

The nodes are smart enough to learn a machine`s parameters and to determine trends in sensor performance. They can perform diagnostic algorithms such as spectral analyses, probabilistic modelling and frequency detection.

The nodes will establish and maintain a network without the user intervening. If nodes are added or removed, the network will sense this and reconfigure itself accordingly.

The HiDRA technology has grown out of an earlier Science Center project called WINS (Wireless Integrated Networked Sensors), a prototype of which monitors motors in the Californian Center`s cooling fluid pump room. You can examine readings from these motors, including bearing vibration levels, by visiting the WINS demonstration Web site.

The HiDRA technology has been tested in factories and on board ships and, according to Jim Duncan, the Center`s director of business development, these early installations have demonstrated the "tremendous promise for this kind of sensor". He predicts that HiDRA will "enable a wider use of monitoring programmes that optimise the use of machinery and improve plant efficiency". The HiDRA system does not use the low-cost Bluetooth radio technology that some industrial developers are starting to adopt (see article, page 22), but researchers at the Rockwell centre are investigating the potential of Bluetooth.