# An Exploration of Robot-Mediated Tai Chi Exercise for Older Adults
## 3 Results
### Participants' Experience of the Robot-Led Tai Chi Exercise (from the Post-Exercise Survey)  
#### 3.3.1 Perceptions of the Robot  
The participants rated 7.85 out of 9 (SD = 1.63) for question 1 (\"Could you understand the robot's speeches?\"), indicating that the robot's speeches were well-understood. From the qualitative feedback, the most common comment was that the robot spoke slowly and clearly, which facilitated understanding. Meanwhile, they also noted that the robot had  
\begin{table}
\begin{tabular}{l c c c c} \hline \hline \multirow{2}{*}{**Movement**} & **First Whole Movement,** & **Last Whole Movement,** & \multirow{2}{*}{**Z**} & \multirow{2}{*}{_p_} \\  & **Mean (SD)** & & & \\ \hline M1. Warm-up & 100 (0) & 100 (0) & 0 & 1.00 \\ M2. Arm-stretch & **85.67 (26.07)** & **98.50 (1.83)** & **-2.05** & _0.04_ * \\ M3. Shift-weight & 95.95 (6.73) & 98 (4.02) & \(-\)0.98 & 0.33 \\ M4. Combo-1 & **84.28 (29.61)** & **99.13 (2.72)** & **-1.96** & _0.0498_ * \\ M5. Combo-2 & 90.34 (17.68) & 65.88 (25.51) & _2.66_ & \textless{}0.01 * \\ M6. Finishing & 75.75 (25.25) & **93.25 (15.92)** & **-2.19** & _0.03_ * \\ \hline \hline \end{tabular}
* Statistical significance.  
\end{table}
Table 2: Wilcoxon signed-rank test results on participants’ movement completion scores.  
\begin{table}
\begin{tabular}{l c c c c} \hline \hline \multirow{2}{*}{**Movement**} & **First Whole Movement,** & **Last Whole Movement,** & \multirow{2}{*}{**Z**} & \multirow{2}{*}{_p_} \\  & **Mean (SD)** & & & \\ \hline M1. Warm-up & 98.85 (2.45) & 99.65 (0.78) & \(-\)1.56 & 0.12 \\ M2. Arm-stretch & **85.03 (14.74)** & **94.20 (5.39)** & **-3.28** & **\textless{}0.01** * \\ M3. Shift-weight & 95.98 (4.95) & 92.40 (6.93) & 3.13 & \textless{}0.01 * \\ M4. Combo-1 & **79.05 (23.08)** & **99.53 (9.43)** & **-2.20** & **0.03** * \\ M5. Combo-2 & _81.63 (14.76)_ & _57.93 (18.09)_ & 3.10 & \textless{}0.01 * \\ M6. Finishing & **55.65 (22.73)** & **72.45 (16.27)** & **-2.44** & **0.01** * \\ \hline \hline \end{tabular}  
* Statistical significance.  
\end{table}
Table 3: Wilcoxon signed-rank test results on participants’ movement accuracy scores.  
an accent (robotic voice). Therefore, occasionally, the participants could not understand words and match them with the movements. Question 2 (\"Could you see the robot's postures clearly?\") received an average rating of 7.70 (SD = 1.22), indicating that the robot's postures were clearly perceived. They also noticed the difference between the robot's body structure (e.g., length ratios and joint motions) and that of a human, and thus some postures may appear distorted. Accordingly, they rated an average of 6.55 (SD = 1.70) for question 3 (\"Could you follow the postures of the robot?\"), showing that they could follow the robot's postures in general, but encountered some difficulties and confusion. The most important factor was that the participants were confused about whether to mirror the robot's postures when facing it (the robot's right corresponded to the participant's left, and vice versa) or perform the same side as instructed verbally by the robot (the robot's right/left corresponded to the participant's right/left). The robot could not accommodate the participants in terms of changing the performing side. Meanwhile, participants pointed out that the movement breakdowns and repeats were helpful.