Wireless Sensor and Actuator Networks for Lighting Energy ...

Given the 256-level dimming capability, this module is competitive with the
most advanced digital dimming ballast on the market, the digital addressable lighting
interface (DALI). This iteration not only further improves the dimming resolution but
also retains all the promising features from the preceding generation, including the linepowered
mote and the ability to toggle the lights on/off. Only five wires need to be
connected to interface this module with the dimmable ballasts. A failsafe mechanism is
also introduced into this actuation module. Should the mote fail for any reason, the
module is automatically bypassed and the lights can be manually turned on or off using
the wall switch as if the actuation module never existed. This actuation module was
adopted in the implementation of the research system in a small shared-space office as
described in Chapter 9.2.
7.4 Initial Implementation on Prototyping Luminaire Structure
The mote photosensors and the wireless ballast actuation module were deployed
and tested on a prototyping luminaire structure. In addition, the mote-FVF algorithm
developed in Chapter 4 along with a simple rule-based control law were also
implemented to form a closed-loop desktop illuminance regulation system.
Furthermore, the mote-FVF algorithm and the control law were coded into the mote
photosensors and the mote-based ballast actuator respectively so that the closed-loop
system could autonomously perform fusion and use the fused data to dim or brighten
the light.
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