## 1 Introduction
[PERSON] and [PERSON] reviewed the technology facilitated research work on ASD care [2]. They divided the technologies used into four categories: (1) virtual reality; (2) dedicated applications; (3) telehealth applications, and (4) robotic based. For each technology category, three research objectives are considered: (1) communication and interaction; (2) social learning and imitation skills; and (3) other miscellaneous. There are several reviews on using a particular technology, such as virtual technology, social robotics, and serious games, to treat individuals with ASD. [PERSON] et al. [3] reviewed about ten-year's work on using socially assistive robots for autism research up to 2012. The focus was on issues related to robot design, human-robot interaction, and system evaluation. The authors specifically highlighted the need to achieve robot autonomy because the operator-controlled method has severe limitations. [PERSON] et al. reviewed 15 papers that reported clinical use of social robots for individuals with ASD as of 2012 [4]. This review focused on four aspects of the studies, including the response of individuals with ASD to robots, the various ways of using robots to elicit behaviors, and using robots to teach social skills, and using robots to provide feedback. The authors concluded that most of the work reviewed were exploratory and had severe limitations. Even though it is not our focus, we find the situation has not been improved in our current review. [PERSON] et al. [5] outlined robot design features, complied a list of robotic systems that have been used for ASD therapy up to 2013,and highlighted a set of activities used for ASD therapy, including imitation, eye contact, joint attention, turn-taking, emotion recognition and expression, self-initiated interactions, and triadic interactions. The article also summarized the roles that could be played by a social robot, including as a diagnostic agent, as a friendly playmate, as a behavior eliciting agent, as a social mediator, as a social actor, and as a personal therapist. [PERSON] et al. (2016) provided a systematic review of research for autism treatment using social robots from a clinical perspective. A major contribution of this review is that it formulated ten questions regarding the essential roles and benefits of robots for ASD treatments, and reported their findings based on the studies that they have collected up to 2015 in light of these questions. [PERSON] et al. (2016) reviewed research on using social robots for autism treatment up to 2016. They pointed out that there is little progress in making social robots as clinical useful for ASD treatment. [PERSON] provided a review on autism research facilitated by virtual reality technology ([PERSON] et al., 2016). This review focuses on the impact of veridicality of the virtual reality technology in autism treatment under two main themes: (1) using virtual environments for learning and intervention for individuals with ASD to better prepare them to handle real world interactions; and (2) using virtual environments to study how individuals with ASD would behave under predefined social scenarios. [PERSON], [PERSON], and [PERSON] (2016) presented a short review of serious games designed for children with ASD to improve their communication skills and social behavior. These games are designed to be played via touch-enabled mobile devices or via traditional computers using a keyboard and a mouse. Very recently, [PERSON] et al. provided a more up-to-date review on using serious games to teach individuals with ASD to improve their social interactions and emotion skills ([PERSON] et al., 2016). They focused on the target skills of the serious games, and the design principles of the games. They also paid attention to whether or not the games have been validated in a clinical population. Different from the above reviews, which predominantly concern clinical issues, we focus on the engineering perspective of autism studies.