Browsing by Author "Wang, I-Jan"

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A Real-Time Wireless Brain-Computer Interface System for Drowsiness Detection
(2010-08-01)
Lin, Chin-Teng
;
Chang, Che-Jui
;
Lin, Bor-Shyh
;
Hung, Shao-Hang
;
Chao, Chih-Feng
A real-time wireless electroencephalogram (EEG)-based brain-computer interface (BCI) system for drowsiness detection has been proposed. Drowsy driving has been implicated as a causal factor in many accidents. Therefore, real-time drowsiness monitoring can prevent traffic accidents effectively. However, current BCI systems are usually large and have to transmit an EEG signal to a back-end personal computer to process the EEG signal. In this study, a novel BCI system was developed to monitor the human cognitive state and provide biofeedback to the driver when drowsy state occurs. The proposed system consists of a wireless physiological signal-acquisition module and an embedded signal-processing module. Here, the physiological signal-acquisition module and embedded signal-processing module were designed for long-term EEG monitoring and real-time drowsiness detection, respectively. The advantages of low ower consumption and small volume of the proposed system are suitable for car applications. Moreover, a real-time drowsiness detection algorithm was also developed and implemented in this system. The experiment results demonstrated the feasibility of our proposed BCI system in a practical driving application.
A Wearable Mobile Electrocardiogram Measurement Device with Novel Dry Polymer-based Electrodes
(2010)
Wang, I-Jan
;
Liao, Lun-De
;
Wang, Yu-Te
;
Chen, Chi-Yu
;
Lin, Bor-Shyh
A Wearable Mobile Electrocardiogram Monitoring System (WMEMS), which mainly consists of a wearable Electrocardiogram (ECG) acquisition device, a mobile phone with global positioning system, and a healthcare server, was developed in this study. Most of telemedicine systems for long-term ECG monitoring focus on the application of communication techniques. However, how to monitor long-term ECG state more comfortably in daily life is also an important issue. In this study, a novel dry foam electrode was designed and applied for the wearable ECG acquisition device in our WMEMS. These novel dry foam electrodes without conduction gels can provide good conductivity to acquire ECG signal effectively, and can adapt to irregular skin surface to maintain low skin-electrode impedance and reduce motion artifacts under movement. Therefore, the wearable ECG acquisition device is suitable for long-term ECG monitoring in daily life. Moreover, by combining with wireless communication technique, our WMEMS can monitor patient's heart rate continuously anywhere in the globe if they are under the coverage of GSM cellular network. Experiment results showed that our WMEMS really provides a good system prototype for ECG telemedicine applications.
Design, Fabrication and Experimental Validation of a Novel Dry-Contact Sensor for Measuring Electroencephalography Signals without Skin Preparation
(2011-06-01)
Liao, Lun-De
;
Wang, I-Jan
;
Chen, Sheng-Fu
;
Chang, Jyh-Yeong
;
Lin, Chin-Teng
In the present study, novel dry-contact sensors for measuring electro-encephalography (EEG) signals without any skin preparation are designed, fabricated by an injection molding manufacturing process and experimentally validated. Conventional wet electrodes are commonly used to measure EEG signals; they provide excellent EEG signals subject to proper skin preparation and conductive gel application. However, a series of skin preparation procedures for applying the wet electrodes is always required and usually creates trouble for users. To overcome these drawbacks, novel dry-contact EEG sensors were proposed for potential operation in the presence or absence of hair and without any skin preparation or conductive gel usage. The dry EEG sensors were designed to contact the scalp surface with 17 spring contact probes. Each probe was designed to include a probe head, plunger, spring, and barrel. The 17 probes were inserted into a flexible substrate using a one-time forming process via an established injection molding procedure. With these 17 spring contact probes, the flexible substrate allows for high geometric conformity between the sensor and the irregular scalp surface to maintain low skin-sensor interface impedance. Additionally, the flexible substrate also initiates a sensor buffer effect, eliminating pain when force is applied. The proposed dry EEG sensor was reliable in measuring EEG signals without any skin preparation or conductive gel usage, as compared with the conventional wet electrodes.
Development of Real-time Wireless Brain Computer Interface for Drowsiness Detection
(2010)
Hung, Shao-Hang
;
Chang, Che-Jui
;
Chao, Chih-Feng
;
Wang, I-Jan
;
Lin, Chin-Teng
In this study, a real-time wireless embedded EEG-based brain computer interface (BCI) system was developed for drowsiness detection in a realistic driving task. Accidents caused by driver's drowsiness behind the steering wheel have a high fatality rate because of the marked decline in the driver's abilities of perception, recognition, and vehicle control abilities while sleepy. Therefore, real-time drowsiness monitoring is important to avoid traffic accidents. In this study, an embedded EEG-based BCI system which includes a wireless physiological signal acquisition module and an embedded signal processing module was designed, and a real-time drowsiness detection algorithm based on our unsupervised approach was implemented in the embedded signal processing module. EEG signal would be monitored and analyzed by the embedded signal processing module, and the warning tone would be triggered to prevent traffic accidents when the drowsiness condition occurred.
Gaming control using a wearable and wireless EEG-based brain-computer interface device with novel dry foam-based sensors
(2012-01-28)
Liao, Lun-De
;
Chen, Chi-Yu
;
Wang, I-Jan
;
Chen, Sheng-Fu
;
Li, Shih-Yu
A brain-computer interface (BCI) is a communication system that can help users interact with the outside environment by translating brain signals into machine commands. The use of electroencephalographic (EEG) signals has become the most common approach for a BCI because of their usability and strong reliability. Many EEG-based BCI devices have been developed with traditional wet- or micro-electro-mechanical-system (MEMS)-type EEG sensors. However, those traditional sensors have uncomfortable disadvantage and require conductive gel and skin preparation on the part of the user. Therefore, acquiring the EEG signals in a comfortable and convenient manner is an important factor that should be incorporated into a novel BCI device. In the present study, a wearable, wireless and portable EEG-based BCI device with dry foam-based EEG sensors was developed and was demonstrated using a gaming control application. The dry EEG sensors operated without conductive gel; however, they were able to provide good conductivity and were able to acquire EEG signals effectively by adapting to irregular skin surfaces and by maintaining proper skin-sensor impedance on the forehead site. We have also demonstrated a real-time cognitive stage detection application of gaming control using the proposed portable device. The results of the present study indicate that using this portable EEG-based BCI device to conveniently and effectively control the outside world provides an approach for researching rehabilitation engineering.
Human Cognitive Application by Using Wearable Mobile Brain Computer Interface
(2010)
Liao, Lun-De
;
Wang, I-Jan
;
Chang, Che-Jui
;
Lin, Bor-Shyh
;
Lin, Chin-Teng
In this study, we demonstrated a Wearable Mobile Electroencephalogram (EEG)-based Brain Computer Interface System (WMEBCIS) with foam-based dry electrodes embedded. According to the previous studies, many kinds of BCI systems have been proposed and target the applications on sensors and information techniques. For daily life EEG monitoring by using the BCI systems, the sensors have employ a key technique for ensuring the data quality. In view of this, a novel dry foam electrode was designed and applied for the wearable EEG acquisition device in our WMEBCIS. The developed dry electrodes can achieve the quick-placement and high signals quality under no skin preparation and without gels applied. Most importantly, due to its softness advantage, the developed electrodes can fit properly on the skin surface to maintain low skin-electrode impedance and reduce motion artifacts under movement. By using the specific mechanism of our wearable EEG acquisition device, it can be worn conveniently and can maintain the electrode-scalp contact area to acquire good EEG signal quality effectively. Therefore, the wearable EEG acquisition device is suitable for long-term EEG monitoring in daily life. In words, our WMEBCIS was also demonstrated for a cognitive application on drowsiness detection.
Novel Dry Polymer Foam Electrodes for Long-Term EEG Measurement
(2011-05-01)
Lin, Chin-Teng
;
Liao, Lun-De
;
Liu, Yu-Hang
;
Wang, I-Jan
;
Lin, Bor-Shyh
A novel dry foam-based electrode for long-term EEG measurement was proposed in this study. In general, the conventional wet electrodes are most frequently used for EEG measurement. However, they require skin preparation and conduction gels to reduce the skin-electrode contact impedance. The aforementioned procedures when wet electrodes were used usually make trouble to users easily. In order to overcome the aforesaid issues, a novel dry foam electrode, fabricated by electrically conductive polymer foam covered by a conductive fabric, was proposed. By using conductive fabric, which provides partly polarizable electric characteristic, our dry foam electrode exhibits both polarization and conductivity, and can be used to measure biopotentials without skin preparation and conduction gel. In addition, the foam substrate of our dry electrode allows a high geometric conformity between the electrode and irregular scalp surface to maintain low skin-electrode interface impedance, even under motion. The experimental results presented that the dry foam electrode performs better for long-term EEG measurement, and is practicable for daily life applications.