The goal of his research is to understand the pathophysiology of obstructive sleep apnoea (OSA). In doing so, the aim is to contribute to the development of newer, more tolerable therapies for patients. Dr Wellman has pioneered new measurement techniques to quantify respiratory control stability (loop gain) during sleep. He continues to work on developing novel tools to define the pathophysiological traits that cause sleep apnoea. He is a world leader in this line of investigation and has expertise in respiratory/upper airway physiology and engineering.