Review of real brain-controlled wheelchairs

This paper presents a review of the state of the art regarding wheelchairs driven by a brain-computer interface (BCI). Using a brain-controlled wheelchair (BCW), disabled users could handle a wheelchair through their brain activity, granting autonomy to move through an experimental environment. A classification is established, based on the characteristics of the BCW, such as the type of electroencephalographic (EEG) signal used, the navigation system employed by the wheelchair, the task for the participants, or the metrics used to evaluate the performance. Furthermore, these factors are compared according to the type of signal used, in order to clarify the differences among them. Finally, the trend of current research in this field is discussed, as well as the challenges that should be solved in the future

Brain switch mode: an alternative to drive a brain-controlled wheelchair

To date, different control paradigms of low level navigation have been tested for brain-controlled wheelchairs, mainly divided into continuous or discrete control [1]. However, these paradigms have certain drawbacks such as the need to keep the mental tasks active for a long time, as in continuous mode, or the impossibility to freely choose any distance of the movement or the turn, as in the discrete mode. An alternative paradigm to solve these problems could be the use of the brain switch mode [2], which would allow a more flexible control of the distance, requiring a lower workload for the user.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Proposals of Control Paradigms Applied to a Brain-Controlled Wheelchair

Proposals of Control Paradigms Applied to a Brain-Controlled Wheelchair, Ron-Angevin R., Velasco-Álvarez F., Fernández Rodriguez A., Proceeding og the BITs 4th Annual World Congress of Smart Material 2018, Osaka (Japan), 6-8 March 2018Several of the neurological diseases that human beings can result in severe disabilities. In some cases, people who suffer from such deficiencies lose any chance of communication with their environment, being the only possible alternative to give the brain a new channel not based on muscular activity, allowing these people to send messages and commands to the external world. The systems that allows the latter is what is known as Brain-Computer Interfaces (BCI). Their common feature is to process the brain’s electrical activity for extracting information that can be used to command an external device, as for example, a wheelchair to provide them some mobility. One of the most important limitations of these brain controlled wheelchair is to guarantee that a person can, through his mental activity, safely control the variety of navigation commands that provide control of the wheelchair: advance, turn, move back, and stop. The vast majority of the mobile robot navigation applications that are controlled via a BCI demand that the user performs as many different mental tasks as there are different control commands, worsening the classification accuracy. In order to enable an effective and autonomous wheelchair navigation with a BCI system without worsening user performance, the Brain–Computer Interface (BCI) group of the University of Málaga (UMA-BCI) proposed and later developed a new paradigm based on the discrimination of only two classes (one active mental task versus any other mental activity), which enabled the selection of four commands: move forwards, turn right, move backward and turn left. The final aim of this contribution is to show how to control a robotic wheelchair through the use of only two mental tasks. The mapping of these two mental tasks into several navigation commands allows the Brain-Controlled Wheelchair to be moved and turned in order to achieve effective navigation.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Switch mode to control a wheelchair through EEG signals

This paper presents a switch strategy to control the movement of a Brain-Controlled Wheelchair. After the activation of a Motor Imagery task, an advance movement is started and kept until the same task stop it. This way, users with an unstable control of their EEG could be aided in handling the wheelchair.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Brain-Computer Interface Control of Smartphone Messaging Applications

This work-in-progress paper presents an implementation of a Brain-Computer Interface (BCI) system focused on the control of the most common messaging applications of a smartphone: WhatsApp, Telegram, e-mail and Short Message Service (SMS). The control of these applications is achieved through the use of a virtual assistant running in the smartphone. The BCI system is based on the visual Row-Column Paradigm (RCP), which allows users to select several control commands and to spell messages that are converted to synthesized voice and received by the mentioned virtual assistant in the smartphone.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Alcohol consumption among University students in Spain

Producción CientíficaAlcohol consumption in 1984 among 2921 students of nine Faculties in the University of Valladolid (Spain) is reported. Alcoholic drinks were frequently consumed, especially by males and during weekends. Per capita consumption was 9.85 l of absolute alcohol/year for males and 4.971 for females. Beer, wine and gin were the favourite drinks. Alcohol consumption was similar in the different faculties and age groups but was to some extent related to age and place of residence in male students. Students' alcohol consumption was not as high as in the general Spanish population, and seems to have been stable during the last 10 years

Influence of process parameters on the corrosion resistance of corrugated austenitic and duplex stainless steels

The main objective of this work is to study the influence of the forming process on two corrugated, lean, duplex stainless steels (DSSs): UNS S32001 and UNS S32304. Both grades have been recently proposed as alternative materials to the austenitic UNS S30403 grade for manufacturing reinforcement bars to be embedded in concrete structures, exposed to corrosive environments. Hot-worked (HW) corrugated bars of both DSSs are analyzed and their corrosion behaviour is compared with that of the HW and cold-worked (CW) corrugated bars of S30403. The corrosion performance is characterized through cyclic polarization curves in 8 different solutions that simulate those contained inside the pores of concrete in different circumstances. The obtained results justify a great interest in the studied lean DSS grades with respect to their use as reinforcements. Moreover, it is proved that the corrugated surface of a bar is clearly less corrosion resistant than the centre of the bar. The processing method of producing reinforcements influences not only the pitting susceptibility but also the pitting morphology.Publicad

Effect on wear resistance of nanoparticles addition to a powder polyester coating through ball milling

Proceeding of: 13th Coatings Science International Conference (COSI 2017),The wear properties of a textured polyester powder coating with pyrogenic silica nanoparticles addition were evaluated. Raw powders of a commercial, textured polyester organic coating were mixed with low amounts of SiO2 nanoparticles (0.5&-3 wt%) using ball milling, a simple and economical method. Nanoparticles were mixed into the powder of thermoset organic coating for 10 min in a two-body planetary ball mill. Particle size distribution of the powder was measured to evaluate the milling effect. The coatings were applied and cured in an industrial installation on aluminum substrates. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images of the coatings were taken to analyze the homogeneity of the organic coating. Roughness, gloss and color were measured in order to evaluate their appearance. The effect of nanoparticles on abrasive and erosion wear performances was measured. Pin-on-disk wear tests were carried out. Erosion measurements were performed with free fall of sand on the samples, a test based on ASTM D968 standard. The results showed that the milling process provides a good distribution of nanoparticles as no agglomerates were found. The addition of 0.5 wt% silica nanoparticles allows for improvement of the wear resistance of the coatings.The authors acknowledge the financial support of Interreg SUDOE, through KrEaTive Habitat project (Ref. SOE1/P1/E0307

Effect of Stimulus Size in a Visual ERP-Based BCI under RSVP

Rapid serial visual presentation (RSVP) is currently one of the most suitable paradigms for use with a visual brain–computer interface based on event-related potentials (ERP-BCI) by patients with a lack of ocular motility. However, gaze-independent paradigms have not been studied as closely as gaze-dependent ones, and variables such as the sizes of the stimuli presented have not yet been explored under RSVP. Hence, the aim of the present work is to assess whether stimulus size has an impact on ERP-BCI performance under the RSVP paradigm. Twelve participants tested the ERP-BCI under RSVP using three different stimulus sizes: small (0.1 × 0.1 cm), medium (1.9 × 1.8 cm), and large (20.05 × 19.9 cm) at 60 cm. The results showed significant differences in accuracy between the conditions; the larger the stimulus, the better the accuracy obtained. It was also shown that these differences were not due to incorrect perception of the stimuli since there was no effect from the size in a perceptual discrimination task. The present work therefore shows that stimulus size has an impact on the performance of an ERP-BCI under RSVP. This finding should be considered by future ERP-BCI proposals aimed at users who need gaze-independent systems.The authors would like to thank all participants for their cooperation. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Partial funding for open access charge: Universidad de Málag

Estudio de la actividad de especies Ir(III)-NSiN en la hidrosililación de dióxido de carbono

En el presente trabajo se ha estudiado la influencia del silano en la actividad y selectividad del complejo [Ir(H)(CF3CO2)(NSiN)(coe)] como precursor catalítico en reacciones de hidrosililación de dióxido de carbono. En primer lugar, se realizó la síntesis y caracterización de dicho complejo siguiendo el procedimiento descrito en la bibliografía. A continuación, se realizaron los estudios catalíticos, identificando los productos finales de las reacciones mediante espectroscopía de RMN. Se observó que la naturaleza del silano influencia la actividad y selectividad de este proceso, aunque no es sencillo establecer una regla general de comportamiento