Proceedings of 2nd International Symposium for Color Science and Art 2020-2021

Development of an interactive systemusing color for analysis and acquisition of balance skills
Yuta Ogai, Masahiko Yamamoto, and Kentaro Kodama*
Tokyo Polytechnic Univ., 1583 Iiyama, Atsugi, Kanagawa 243-0297, Japan* Tokyo Metropolitan Univ., 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, JapanABSTRACT

The experiment participants were 3 males (A, B, and C)
in their 20s. We gave the participants the task of standingon the stabilometer with one dominant foot for 2 seconds.
If a participant cannot stand up for 2 seconds, the data isrecorded while he did stand up. We asked them to respondto the question, "Was it easy for you to maintain balance?"by hitting a dot on a line with the two ends indicating Easyand Hard.
The obtained data were evaluated in terms of dynamic
stability using detrended fluctuation analysis (DFA) [2].

Dynamic balance ability evaluation is difficult.
Therefore, we configured an experiment to investigate theeffect of vision on balance and discuss a method toevaluate dynamic balance ability. We found that
detrended fluctuation analysis (DFA) scaling exponents ofcenter of pressure (CoP) changed when there was a visual
influence, suggesting that there is an influence on the way
we balance. We consider that it will lead to theconstruction of an interactive system using CoP sway andvisual feedback.
1. INTRODUCTION
Static balance ability can be evaluated by capturing
the movement of the center of pressure (CoP). However,dynamic balance ability evaluation is difficult, and there iscurrently no gold standard evaluation method. Therefore,
we configured an experiment to investigate the effect ofvision on balance and discuss a method to evaluate
dynamic balance ability. We also discuss how to construct
an interactive system for dynamic balance ability.
2. METHOD
We used a stabilometer manufactured by TAOS Institute(Fig. 1) to measure CoP for experiment participants (20Hz)[1]. The stabilometer is placed 1 m in front of a 42-inch fullhigh-definition monitor (Fig. 2). The direction toward themonitor is the Y-axis of the stabilometer, and the horizontal
direction is the X-axis. The monitor shows a pattern of reddots, as shown in Fig. 3. We conducted two types ofexperiments with static dots and moving dots. In themoving dots experiment, the dots moved to the right at aspeed of about 0.6 m/s.

Fig. 2 The scene of the experiment.

Fig. 1 Stabilometer (TAOS Institute, Inc.)

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Proceedings of 2nd International Symposium for Color Science and Art 2020-2021
4. DISCUSSION
The results of the questionnaire indicate that this onelegged balancing task is influenced by vision. Results ofDFA suggested that dynamic visual information might
affect the postural control strategy and it could be shownin the structure of CoP. Thus, using DFA scaling
exponents, it is possible to quantitatively evaluate theeffect of vision and color on balance ability. However, westill need to increase the number of participants and thenumber of experiments.
For future work, we think that by using a screen to provide
visual feedback on CoP sway information, we canconstruct an interactive system in which the user interacts
in front of the screen like Chaotic Video Feedback [3], asshown in Fig. 6.

Fig. 3 Pattern of red dots shown on the monitor.
3. RESULTSThe question results are shown in Fig. 4. The data areprocessed on a scale from 1 to -1, with Easy being 1 andHard being -1. The result of Participant A for static dots isshown as A(Static), and the result for moving dots isshown as A(Moving). All participants answered that theexperiment with the moving dots was more difficult than
the static dots.

Fig. 6 Chaotic Video Feedback: Example of aninteractive system using a screen [4].
5. CONCLUSION
We constructed an experimental environment to study
the effect of vision on CoP sway and conducted anexperiment. We found that the DFA scaling exponentschange when there was a visual influence, suggesting that
there is an influence on the way we balance. We consider
that this result will lead to the construction of an interactive
system using CoP sway and visual feedback.

Fig. 4 The results of the question, "Was it easy for
you to maintain balance?"
The result of DFA of CoP in the X-axis direction is shownin Fig. 5, where DFA1 means fast-scale, and DFA2 means
slow-scale. Although DFA1 and DFA2 are lower formoving dots than static dots for all participants, the DFA
scaling exponents should be carefully interpreted in futurestudies with more data.

6. REFERENCES[1] Stabilometer with Fluctuation Analysis,
http://www1310gj.sakura.ne.jp/images/4.pdf,
accessed on 2021-02-08, in Japanese[2] Peng, C.K., et al., "Mosaic organization of DNA
nucleotides," Physical Review E, 49 (2), 1685–1689,1994.
[3] Ogai, Y., "The Introduction of the 5th Exhibition at thecol.lab Gallery," Proceedings of 2nd International
Symposium for Color Science and Art 2020, 2020.
[4] Col.lab gallery "Talking with Color,"
https://youtu.be/xie-X9cMJlM, accessed on 202102-08

Fig. 5 The result of DFA of CoP in the X-axis
direction.

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