With the
UWB technology, each AVC module can transmit and receive data with another such module, says Jon Hedges, Time Domain's director of sales and marketing, using about 30 microwatts of power. In that way, he explains, the module can determine the other device's location.
The Autonomous Vehicle Control module will be attached to the 60-foot ship, as well as to two trees and a set of gates, all of which will be mobile. As the props and scenery pieces move around the stage, each AVC module will capture transmissions from the other modules, as well as from six UWB
RFID transceivers attached above the stage in order to improve location granularity.
Each AVC module transmits a signal pulse between 3.1 and 5.3 GHz, and is encoded with its own unique ID number, as well as
sensor data. Other modules receive the pulse and forward that data, along with their own unique identifiers. That response is received by an access point that routes the information to iTrack's software. The software then determines the "flight time"—that is, the amount of time required for an AVC module to receive signals from other modules or overhead transceivers, and to utilize data from the module's sensors—such as compass location—in order to fine-tune the tagged prop's location. The data from the AVC modules and UWB transceivers, Atkinson says, enables the iTrack software to calculate an object's positioning within a few centimeters, at a rate of 10 times a second. That information is then fed to the Niscon stage-management system, to instruct each prop's Vetex drive unit where to move next.
Additionally, the software data is displayed for the stage manager, who can manually override the automated operation if he or she sees a problem with the set—for example, a prop moving too close to an actor. Individuals on stage can also halt the prop's movement using a joystick controller.
Sight and Sound Theatres intends to use the system for three more stage plays following the Jonah production. According to Atkinson, the solution can also be marketed to other theaters, as well as to any business or organization that operates automated, unmanned vehicles.