# Peer-to-Peer Ultra-Wideband Localization for Hands-Free Control of a Human-Guided Smart Stroller
## 7 Conclusions and Future Work  
In this work, we designed a hands-free human-guided smart stroller. We investigated the users' preference for the relative following position and proposed a human-guided control system using the UWB localization system. The interaction in the proposed system allows the user to operate the smart stroller intuitively and ensures that the stroller remains within an appropriate range of the user. An experiment was conducted indoors to assess the proposed interface's usability and effectiveness compared to a virtual joystick and manual operation. The results showed that the proposed system achieved an SUS score comparable to the joystick in terms of usability, yet inferior to manual operation. Notably, among the female participants the SUS score surpassed the joystick in usability and was comparable to the manual operation. Moreover, the proposed interface significantly reduced the physical demand compared to the manual operation on the occasion when the user's hands were occupied. The proposed system is designed for a baby stroller; however, it can also be generalized to wheelchairs for caregiving scenarios.  
The proposed system has the following limitations. The design principle of the proposed system focuses on the ease of implementing a UWB localization-based smart stroller, meeting the basic requirements for stroller control. We assume that the usage scenario for human-guided smart strollers is in less crowded, open areas such as parks. Therefore, we did not place excessive emphasis on collision avoidance. This will decrease the risk of collision when the user drives the stroller. An improved controller with a simple collision avoidance function will be considered in future works. Additionally, only a subset of the participants in the current evaluation experiment were actual parents. Considering that parents and non-parents might exhibit different capabilities and responsibilities in using strollers, the results may not fully reflect parental behavior. Consequently, future research will specifically target parents to more effectively assess the proposed system.  
Conceptualization, X.Z., Y.C., M.H., and K.S.; methodology, X.Z., Y.C., M.H., and K.S.; software, X.Z.; validation, X.Z. and Y.C.; formal analysis, X.Z.; investigation, X.Z.; resources, X.Z.; data curation, X.Z.; writing--original draft preparation, X.Z. and Y.C.; writing--review and editing, M.H. and K.S.; visualization, X.Z.; supervision, M.H. and K.S.; project administration, K.S.; funding acquisition, K.S. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the Japan Science and Technology Agency (JST) for the CREST research project on Social Signaling (JPMJCR19A2) and the Japan Society for the Promotion of Science KAKENHI [grant number 23H00485].  
The study was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee of the University of Tsukuba (Approval No.2023R804, 28 November 2023).  
Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.  
Data Availability Statement: Data are contained within the article.  
The authors declare no conflicts of interest.