Designing systems with humans in the loop to assist users is an active research area with potential societal impact. Investigations require many innovations, tools, and evaluation criteria, even compared to fully autonomous systems. Implementing such systems demands significant effort to achieve reliability and raises issues related to usability, privacy, and acceptability. Moreover, multidisciplinary competencies are needed to adapt algorithms to industrial, social, medical, and economic constraints. The goal is to provide a view of how recent findings in computer vision and robotics are changing assistive technologies, emphasizing related issues and how researchers in various fields have addressed them.