Lübeck offers a number of different testbeds, all accessible through the already mentioned WISEBED experimental facility features such as the testbed runtime, portal servers, etc.
UZL’s major testbed consists of three sensor node hardware types: iSense, TelosB, and Pacemate. The nodes are arranged in clusters. Each cluster has one sensor node of each node type as shown in Figure 1. This testbed consists of roughly 300 stationary sensor nodes organized into 100 clusters. There are two different cluster layouts which differ in the sensor module connected to the iSense node. Half of the iSense sensor nodes are equipped with temperature and light sensors while the remaining nodes are equipped with a passive infrared sensor and accelerometer sensors.
|Figure 1: UZL cluster with an iSense, Pacemate and TelosB mote||Figure 2: Roomba with iSense node|
All clusters are connected to a total of 35 Acer Aspire One netbooks forming the backbone of the testbed connected to the Internet. The sensor nodes are connected to the netbooks via USB. The netbooks are connected to the Internet over 802.11g Wi-Fi using a testbed-private ESSID and enterprise WPA2 encryption. This backbone enables the user to program or reset the sensor nodes without the need of an additional OTAP (Over-the-Air-Programming) protocol. The fixed network can be extended by mobile nodes (Roomba cleaner robots (see Figure 2) with attached iSense sensor nodes and with Lego Mindstorms).
|Figure 3: An outdoor node||Figure 4: Outline of the outdor testbed|
In addition to the indoor and mobile nodes, UZL has deployed a number of outdoor, solar-powered iSense sensor nodes (see Figure 3). It features a 6000mAh rechargeable battery pack, an iSense Solar Power Harvesting System which recharges the battery during sunlight times and provides energy from the battery otherwise. It also features an infrared sensor capable of detecting movement. Currently, approximately 35 nodes are deployed in the garden of the University of Lübeck’s manor house (see Figure 4).