The 2022 3rd International Conference on Internet of Things, Artificial Intelligence and Mechanical Automation (IoTAIMA 2022) was held virtually on July 22-24, 2022 in Shanghai, China. The conference provided a communication forum for the international experts and researchers in the fields of Internet of Things, Artificial Intelligence and Mechanical Automation to share research achievements, explore solutions to research challenges, encourage international collaborations, and boost development of science and technology.In the conference, we were greatly honored to have Prof. Ke Zhang from Shanghai Institute of Technology, China to serve as our Conference Chair. 120 individuals around the world took part in the conference. Divided into three parts, the conference agenda included keynote speeches, oral presentations and online Q&A discussion. Primarily, the keynote speakers were each allocated 30-45 minutes to address their speeches. Then in the next part, oral presentations, the excellent papers we had selected were presented by their authors one by one.Four distinguished professors were invited to hold keynote speeches during the conference. Among them, Prof. Xiaodong Liu from Dalian University of Technology performed a thought-provoking speech on Knowledge Discovery and Semantic Learning in the Framework of AFS Theory. Under the background that AFS theory gains increasing interest from various research fields, this survey aimed to report the current developments of theoretical research and practical advances on AFS theory. Firstly some notions and foundations of AFS theory with an illustrative example were reviewed and then various extensions of AFS theory for knowledge discovery were analyzed. And then Prof. Yudong Zhang from University of Leicester addressed a speech: Artificial Intelligence Theories and Methods for COVID-19 Recognition. In this research, CT scan, a medical imaging technique used in radiology to get detailed images of the body noninvasively for diagnostic purposes, was applied to discuss the recent AI theories and methods in chest CT-based COVID-19 diagnosis. Two other chest-related diseases: secondary pulmonary tuberculosis and community-acquired pneumonia, were covered in the study. Their insightful speeches had triggered heated discussion. And every participant praised this conference for disseminating useful and insightful knowledge.We are glad to share with you that we received lots of submissions from the conference and we selected a bunch of high-quality papers and compiled them into the proceedings after rigorously reviewing them. These papers feature but are not limited to the following topics: Radio Frequency Identification, New Sensing Technology, Intelligent Perception Systems, Unmanned System Control Technology, Automation etc. All the papers have been checked through rigorous review and processes to meet the requirements of publication.We would like to acknowledge all of those who supported IoTAIMA 2022 and made it a great success. Particularly, we would like to thank the Journal of Physics: Conference Series, for all the efforts of its colleagues in publishing this paper volume. We sincerely hope that the IoTAIMA 2022 turned out to be a forum for excellent discussions that enable new ideas to come about, promoting collaborative research.Committee of IoTAIMA 2022List of Committee member is available in this pdf.