Wireless Sensor and Actuator Networks for Lighting Energy ...

acquisition and wireless transmission in accordance with the change of daylight. The
adaptive sensing algorithm employs prediction theories and the simple exponential
smoothing method to detect the change of daylight, and adapts the sensing rate with a
set of fuzzy rules.
The optimal lighting actuation algorithm optimizes the light settings for each
luminaire to minimize the overall energy usage while delivering the desired lighting
specified by present occupants. People have diverse lighting preferences and
requirements [6, 7], which are not possible to satisfy with a single universal light
setting. Exploiting the individual controllability of the wirelessly enabled luminaires,
each lighting fixture can be actuated at a different level to deliver optimal lighting that
meets all the occupants’ requirements. While the lighting is driven by the occupants’
preferences, energy consumption is also minimized during the optimization. The
optimal lighting actuation algorithm applies the theory of optimization and formulates
lighting control into a linear programming problem with minimizing energy
consumption as the objective function and satisfying occupants’ lighting preferences as
the constraints.
1.3.2 Implementations
This part of the work concerns designing the hardware for enabling wireless
capabilities of the lighting control components as well as building prototyping systems
for verifying different aspects of the theoretical framework. Photosensor boards are
designed to attach to the wireless platforms to function as wireless photosensors, and
wireless actuation modules integrated with wireless platforms are developed for
6