This paper proposes a concept of the task-oriented software synergy (TOSS) as a novel control method for anthropomorphic hands and a control system of multi-fingered hand that realizes TOSS. TOSS is able to perform various tasks with fewer inputs than conventional synergy by switching synergy for each task. By comparing TOSS with the conventional synergy, we show that TOSS gained higher contribution rate than the conventional synergy for writing task and smaller error of joint angle due to the effect of dimensional reduction. Moreover, we verified through physics simulation that the success rate of a task using TOSS with a few principal components is higher than conventional synergy based method. These results show that TOSS can properly perform various tasks with fewer inputs.
The purpose of this study was to clarify the development pattern of batting imagery in youth baseball players. One hundred thirty-eight young baseball players (6–14 years old) were divided into 4 age groups. Tee and toss batting with a stationary tee stand and toss machine were used in the batting trials. In addition, the participants did an imagery task of hitting the optimal point of a ball where they wanted to impact it. To clarify the difference between the image trial and actual batting (tee and toss), the absolute error distance (AED) was calculated by subtracting the impact distance of the image trial from that of the actual batting. Two-way analysis of variance (4 age groups × tee and toss images) revealed that the AED was significantly lower in the 11- to 12-year-old players than in the 6- to 8-year-old players (p < 0.001). The relationships between the tee and toss images showed a significant correlation in all 4 groups (6–8 years old: r = 0.445, 9–10 years old: r = 0.495, 11–12 years old: r = 0.589, and 13–14 years old: r = 0.804; all groups: p < 0.001) and that tee and toss batting imagery appears unchanged as age increases. However, batting imagery seems to develop around 11-12 years old, and at the age group of 13-14 years old players are able to impact the same position on the bat regardless of the batting trials.
This paper proposes a concept of the task-oriented software synergy (TOSS) for anthropomorphic hands and designs a control system of multi-fingered hand that realizes TOSS. By using TOSS, we can perform various tasks with fewer principal components than those of conventional synergies by switching synergy corresponding to each task. We show that TOSS can be realized with lower approximation error and higher contribution rate than the conventional synergy for a given task. Moreover, we verified through physics simulation that an adverse effect of dimensionality reduction is smaller than conventional synergy. These results show that, by using TOSS, we can properly perform various tasks with fewer inputs.