First and foremost, I would like to express my sincere gratitude to my advisors Dr. Siddhartha Srinivasa and Dr. Stephanie Rosenthal, who have greatly helped me in motivating me to keep proactive and hardworking, shaping my interests in human-robot interaction, inspiring, supporting, and formalizing my research ideas, and directing me through social networking and career path planning. I am also extremely grateful to my commi ee member Dr. Reid Simmons for his ideas and feedbacks all along my Masters research, and to my colleagues Dr. Henny Admoni and Dr. Daqing Yi for their invaluable advices condensed from their solid technical skills, rich life experiences, and kindest hearts. Their vision, guidance and knowledge have been invaluable in my work and life. It has been a great honor to work with them. I would like to thank Rosario Scalise as my "wonder twin" collaborator throughout my thesis work. I enjoy bouncing my ideas with him who always delivers me his innovative and comprehensive explanations, in both natural language and demonstration on computer, optimized for the maximal clarity and fun. I also thank him for encouraging me to network with people in conferences as a sincere friend. Further, I would like to thank all my fellow lab-mates as well