Howard Memorial Finds RFID Keeps Assets From Getting Lost

Skytron installed approximately 90 ZigBee sensor units, which function similarly to RFID interrogators, throughout the facility's nine buildings, and the hospital attached about 300 Awarepoint battery-powered tags to the assets. Each tag stores a unique ID number that it transmits to those sensor units, says Bryant Broder, Skytron's senior product manager. It also comes with a slide switch that workers can move from one side of the tag to another, thereby changing the transmission data to indicate a change in the asset's condition, such as needing to be serviced.

With the system in place, Broder says, a tag is usually in read range of at least 15 sensor units within the vicinity—to help pinpoint its location—which, in turn, transmit back to a bridge unit. The bridge unit calculates the tag's location within several meters, then sends that information, along with the tag's ID number and status (such as requiring service), via a wired LAN connection to the hospital server, which uploads it to Skytron's network operations center. Skytron software then interprets and displays the data on a Web site accessible only by authorized users.

Skytron's Bryant Broder

Employees must sign onto the system using their user name and password, and are granted access to predetermined amounts of data regarding the asset's location and status. Staff members can utilize the system to locate an item, determine its status and history, and learn when that asset may need servicing in the future. The system can also send alerts to authorized users when an unexpected action occurs, such as a specific item leaving at an unscheduled time or through an unexpected doorway, thus indicating a possible theft.

An integrated optical sensor can detect if a tag has been removed from the item to which it is attached, causing the tag to send an alert. A built-in accelerometer then helps the system determine whether that tag is moving or stationary.

The system is also self-healing and self-calibrating, so that if one sensor node goes down, data is still transmitted through the others. Skytron software monitors the nodes' health, and sends an alert in the event that one of the sensors is not operating properly.

Currently, Peterson says, the hospital's staff uses the Skytron Asset Manager software to search for items an average of 750 times per month.