Two-Step Input Spatial Auditory BCI for Japanese Kana Characters

Studies so far have analyzed the effect of distractor stimuli in different types of brain–computer interface (BCI). However, the effect of a background speech has not been studied using an auditory event-related potential (ERP-BCI), a convenient option when the visual path cannot be adopted by users. Thus, the aim of the present work is to examine the impact of a background speech on selection performance and user workload in auditory BCI systems. Eleven participants tested three conditions: (i) auditory BCI control condition, (ii) auditory BCI with a background speech to ignore (non-attentional condition), and (iii) auditory BCI while the user has to pay attention to the background speech (attentional condition). The results demonstrated that, despite no significant differences in performance, shared attention to auditory BCI and background speech required a higher cognitive workload. In addition, the P300 target stimuli in the non-attentional condition were significantly higher than those in the attentional condition for several channels. The non-attentional condition was the only condition that showed significant differences in the amplitude of the P300 between target and non-target stimuli. The present study indicates that background speech, especially when it is attended to, is an important interference that should be avoided while using an auditory BCI.

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Trajectory and Vibration Control of a Single-Link Flexible-Joint Manipulator Using a Distributed Higher-Order Differential Feedback Controller

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4035873 ◽

2017 ◽

Vol 139 (8) ◽

Cited By ~ 11

Author(s):

John T. Agee ◽

Zafer Bingul ◽

Selcuk Kizir

Keyword(s):

Trajectory Tracking ◽

Higher Order ◽

Feedback Controller ◽

Step Response ◽

Position Measurement ◽

Tracking Errors ◽

Flexible Joint ◽

Nonminimum Phase ◽

Step Input ◽

Flexible Joint Manipulator

The trajectory tracking in the flexible-joint manipulator (FJM) system becomes complicated since the flexibility of the joint of the FJM superimposes vibrations and nonminimum phase characteristics. In this paper, a distributed higher-order differential feedback controller (DHODFC) using the link and joint position measurement was developed to reduce joint vibration in step input response and to improve tracking behavior in reference trajectory tracking control. In contrast to the classical higher-order differential (HOD), the dynamics of the joint and link are considered separately in DHODFC. In order to validate the performance of the DHODFC, step input, trajectory tracking, and disturbance rejection experiments are conducted. In order to illustrate the differences between classical HOD and DHODFC, the performance of these controllers is compared based on tracking errors and energy of control signal in the tracking experiments and fundamental dynamic characteristics in the step response experiments. DHODFC produces better tracking errors with almost same control effort in the reference tracking experiments and a faster settling time, less or no overshoot, and higher robustness in the step input experiments. Dynamic behavior of DHODFC is examined in continuous and discontinues inputs. The experimental results showed that the DHODFC is successful in the elimination of the nonminimum phase dynamics, reducing overshoots in the tracking of such discontinuous input trajectories as step and square waveforms and the rapid damping of joint vibrations.

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Copying, Reading, and Writing of Kana and Simple Forms by Japanese Preschoolers

Perceptual and Motor Skills ◽

10.2466/pms.1988.66.2.387 ◽

1988 ◽

Vol 66 (2) ◽

pp. 387-394

Author(s):

Jun Yamada ◽

Miyuki Sasaki ◽

Naoko Motooka

Keyword(s):

Multiple Regression ◽

Good Predictor ◽

Quality Measure ◽

Writing Achievement ◽

Regression Analyses ◽

Reading And Writing ◽

Conventional Form ◽

Form Quality ◽

Japanese Kana ◽

Children's Reading

42 Japanese preschoolers were administered tasks of copying, reading, and writing of Japanese kana (cursive syllabic letters) and simple forms. Multiple regression analyses were used to determine whether two kana-copying measures, speed and span, make significant contributions to children's reading and writing achievement after a conventional form-quality measure had been controlled. Analysis showed that speed or span accounts uniquely for a significant and sizable amount of the variance of reading and writing, suggesting that kana-copying is a good predictor of reading and writing for Japanese preschoolers.

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