## 6 Conclusions and Future Work  
In accordance with the ultimate objective of employing a robot patient in the training of STS transfer skills and assessing the performance of these skills, the joint torque and external torque were measured at the robot's lower limbs. In addition, a control method was proposed to reproduce the patient's STS movement depending on the nurse's skill. To achieve such requirements, this study adopted admittance control of motor movement by an external force. Both the direction and quantity of the external torque measured at the hip joint served as the variables to control the robot's standing movement. The robot's lower limbs were redesigned from passive and free joints to a full complement of active joints with compliant units, which allowed the external force to be measured and the stiffness of a human joint to be reproduced.  
According to the results obtained in this study, the minimum and average values of the joint torque and the average value of the external torque, measured during phase I of the STS transfer, revealed a significant difference when the incorrect method was used. The maximum and average joint torque values and the external torque in the hip joint, measured during phase II of the STS transfer, increased when the incorrect method was used. However, the maximum external torque in the knee joint did not reveal a significant difference because the nurse provided support at the waistband, which is anatomically positioned very far from the knees. Moreover, the average joint torque can reflect the dynamic status of the robot patient. However, data cannot be used to assess the skill applied by the nurse when the current limitation of the motor is lowered, as the difference in measurements may fail to be significant.  
In the future, a larger variety of incorrect transfer methods will be included in the system, and the threshold of each step will be determined by employing a larger number of participants. Furthermore, the learning effectiveness will be measured by comparing the pre- and post-test measurements, which will allow examination of improvements in applying skills gained through practice with the robot patient. Finally, applications for practice with robot patients are expected to extend to other patient handling skills.  
**Author Contributions:** [PERSON], [PERSON] and [PERSON] conceived and designed the study; the robot development and data analysis were done by [PERSON]; also [PERSON]-P., [PERSON], [PERSON] and [PERSON] contributed the nursing acknowledge performed the experiments; [PERSON] assisted the experiment and the controlling of robot; [PERSON] participated into the discussion. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This work was partially supported by JSPS KAKENHI Grant Number 20H04261, 19H05730, and 19H04154.  
**Institutional Review Board Statement:** All procedures were approved by the Ethics Committee at the University of Tokyo, and all participants provided their written informed consent prior to enrollment  
**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study. Also written informed consent has been obtained from the patients to publish this paper.  
**Data Availability Statement:** The data used to support the findings of this study are available from the corresponding author upon request.  
**Acknowledgments:** For the development of the robot patient, the hardware of reduction gear was supported by TPI Co., Ltd.  
**Conflicts of Interest:** The authors declare no conflict of interest. Also the funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.