Date of Award


Embargo Period


Degree Type


Degree Name

Doctor of Philosophy (PhD)




Vivian Loftness

Second Advisor

Volker Hartkopf

Third Advisor

Artur Dubrawski

Fourth Advisor

Gerry Mattern


Current existing thermal control systems are operated based on thermal comfort models generated by regression formulas averaging the thermal responses over data collected during extensive experiments involving panels of human subjects. These models may not be appropriate for an individual whose physiological characteristics happen to be located outside of the main stream from the experimental sample of occupants. By necessity, existing automatic control systems disregard individual characteristics such as health, age, gender, body mass, etc., which may affect physiological responses. Thereby these systems have serious limitations in ensuring individual thermal satisfaction.

While there have been many efforts to overcome the limitations of current technology and to improve individualized control, most of the attempts to make smart controllers for buildings have dealt primarily with optimizing mechanical building components to deliver uniform conditions, largely ignoring whether a generated thermal environment by building systems meet actual users’ comfort and satisfaction. Over-cooling and over-heating are common unnecessary results.

Thermal control innovations for building mechanical systems are critically needed to demonstrate that meeting the physiological needs of occupants can actually save energy and improve environmental quality while enhancing user satisfaction.

The thermoregulation of the human body has a biological mechanism, homeostasis, which enables it to maintain a stable and constant body temperature by changing physiological signals including skin temperatures and heart rate. These signal patterns have the potential to provide information about each individual’s current thermal sensation.
The goal of this research is to establish an adaptive thermal comfort control driven by ongoing human physiological responses or bio-signals. Confirming the optimum driver of skin temperature, and location of sensors, the bio-sensing adaptive control logic is developed to support the optimum control of HVAC terminal units. The bio-sensing controllers offer major opportunities for office, healthcare and residential buildings, especially where environmental quality and control can be linked to productivity and health, and where energy savings are critical. The CoBi bio-sensing adaptive HVAC systems control research would substantially improve occupant comfort, health, and well-being while advancing environmental sustainability with energy savings, at a small first cost for existing or new buildings.