Prof Xie led many government funded research projects as Principal Investigator and so far has completed over 50 funded research projects totalling over £27M of research contracts from government granting agencies and industries. The projects he led have been closely engaged with local and international industries. For example, the project “REST: Reconfigurable lower limb Exoskeleton for effective Stroke Treatment in residential settings” , funded by EPSRC/UK (£1.8M), works closely with industrial and medical partners. Another project “Novel Enabling Technology for Wearable Assistive Devices” funded by FoRST was selected as the key international collaborative project between New Zealand and China. He also led 5 overseas projects totalling over $5M, funded by the National Natural Science Foundation of China and the Federal Ministry of Education and Research of Germany. He has also actively contributed to other large government funded projects. One project he involved as an Associated Investigator was supported by The Medical Technologies Centre of Research Excellence (CoRE) totalling $23M from 2015 to 2020.

Prof Xie has published > 400 refereed papers and 8 books in areas largely related to advanced robotics and mechatronics technologies for medical and rehabilitation. He has supervised over 100 postgraduate students in the field of Mechatronics and Robotics Engineering including 23 post-doctoral fellows/visiting fellows, 75 PhDs, 38 MEng students, and over 140 BE project students. Prof Xie has been recognised internationally as world leader in the field of Mechatronics and Robotics. He was invited to be the Editor or Technical Editor of five reputable international journals. He was the Technical Editor of IEEE/ASME Transaction on Mechatronics (2013-2017), the Editor-in-Chief for the International Journal of Biomechatronics and Biomedical Robotics; the Associate Editor of International Journal of Mechatronics and Manufacturing Systems, International Journal of Advanced Mechatronic Systems, and International Journal of Mechatronics and Intelligent Manufacturing. He was invited to be a national or international panel member by funding organisations from the Foundation for Research, Science and Technology of NZ, the NSERC Discovery grant/Partnership grant of Canada, the National Natural Science Foundation of China, and the National Science Foundation of Korea.