The usability of natural user interfaces for gameplay - Fouche, Rouxan Colin (University of the Free State, 2015)
This study aimed to determine to what extent the usability of a two dimensional game was influenced by the use of a Natural User Interfaces (NUI) as opposed to a traditional keyboard and mouse combination. Two multimodal NUIs were investigated during the study. The first NUI combination (BCIG) made use of the Peregrine gaming glove for the activation of commands, combined with the Emotiv’s accelerometer for control of the cursor. The second NUI combination (BCIF) made use of facial expression recognition, offered by the Emotiv Brain Computer Interface (BCI), as a method of command activation in combination with the Emotiv’s built-in accelerometer for cursor control. A shooting genre game was developed and three tasks were included during development to simulate gaming actions. The first task used only stationary targets, the second task used predictable moving targets, whereas the third task made use of unpredictable moving targets. Since the Emotiv BCI allows for customisation of the accelerometer sensitivity settings, a pilot study was conducted to determine whether the low, medium or high sensitivity setting would provide the best cursor control. The low sensitivity resulted in the fastest gameplay overall as well as the least number of errors. It could thus be concluded that the lowest setting is the optimal setting since it provided the most efficient control for three out of the four metrics tested. After implementing this result, user testing, which involved 5 sessions per participant (n=18), was conducted. Data for three metrics was gathered during user testing, which included data on effectiveness, efficiency and learnability. Post-test questionnaires were administered to assess the level of user satisfaction with each NUI. The results of this study indicated that there is a difference between the usability of the traditional input combination, the keyboard and mouse, and the two NUIs investigated in this study. With regard to the effectiveness and efficiency metrics the traditional input combination was found to be the best, closely followed by BCIG. The three interfaces showed dissimilar levels of improvement, with the traditional keyboard and mouse combination showing the least, followed by BCIG, while the best improvement was noticed for BCIF. By analysing the subjective data gathered from post-test questionnaires, it was found that participants initially enjoyed using BCIG, and after several sessions their level of satisfaction improved. In comparison, the participants initially experienced a slightly negative feeling towards BCIF, which then improved over several sessions to a positive overall response. In conclusion, the keyboard and mouse combination provided far more effective and efficient input, with one exception being the fast command activation when making use of the Peregrine glove, where the two interfaces compared well. It was found that a significant obstacle in the way of NUIs is the existing skill and acceptance that computer users have with the traditional interface combination. Consequently, for individuals to accept and migrate to a more natural interface the new interface will have to provide more effective and efficient input than what is already achievable with the keyboard and mouse combination.

Hierdie studie het gepoog om te bepaal tot watter mate die bruikbaarheid van 'n twee-dimensionele speletjie beïnvloed word deur die gebruik van 'n natuurlike gebruikerskoppelvlak (NUI) in teenstelling met 'n tradisionele sleutelbord-en-muis kombinasie. Tydens die studie is twee multimodale NUIs ondersoek. Die eerste NUI kombinasie (BCIG) het van die Peregrine-handskoen gebruik gemaak vir die aktivering van opdragte in kombinasie met die Emotiv se versnellingsmeter (“accelerometer”) vir die beheer van die posisiemerker. Die tweede NUI kombinasie (BCIF) het gebruik gemaak van die Emotiv Brein-rekenaarkoppelvlak (BCI) se gesigsuitdrukking-herkenning funksie vir opdrag-aktivering in kombinasie met die versnellingsmeter vir posisiemerker beheer. 'n Skiet-genre speletjie is ontwikkel en drie take is ingesluit tydens die ontwikkeling om die aksies van rekenaarspeletjies na te boots. Die eerste taak maak gebruik van stilstaande teikens, die tweede taak van voorspelbare bewegende teikens, terwyl die derde taak gebruik maak van onvoorspelbare bewegende teikens. Aangesien die Emotiv BCI toelaat vir die verstelling van die versnellingsmeter se vlakke van sensitiwiteit is 'n loods-studie gedoen om te bepaal of die lae, medium of hoë sensitiwiteit stelling die beste muis-beheer sal voorsien. Die lae sensitiwiteit was verantwoordelik vir die algehele vinnigste spel sowel as die minste aantal foute. Dit kan dus afgelei word dat die laagste stelling die beste stelling is aangesien dit die doeltreffendste beheer vir drie van die vier metings verskaf het. Na die implementering van die resultaat is gebruikerstoetse gedoen, waar 5 sessies per deelnemer (n = 18) voltooi is. Data vir drie metings is versamel tydens die gebruikerstoetse, insluitende data ten opsigte van effektiwiteit, doeltreffendheid en leerbaarheid. Post-toets vraelyste is voltooi om die gebruikers se vlak van tevredenheid ten opsigte van die NUI te evalueer. Die resultate van hierdie studie het aangedui dat daar 'n verskil tussen die bruikbaarheid van die tradisionele kombinasie, die sleutelbord en muis, en die twee NUIs voorkom. Daar is gevind dat die tradisionele kombinasie gevolg deur BCIG die beste is met betrekking tot die effektiwiteit- en doeltreffendheidmetings. Die drie koppelvlakke het uiteenlopende vlakke van verbetering getoon. Die tradisionele sleutelbord-en-muis kombinasie het die minste verbetering getoon, gevolg deur BCIG, terwyl die beste verbetering opgemerk is vir BCIF. Deur die ontleding van die subjektiewe data wat uit post-toets vraelyste verkry is, is daar gevind dat die deelnemers aanvanklik die BCIG geniet het, en na 'n paar sessies het hul vlak van tevredenheid verbeter. In vergelyking hiermee het die deelnemers aanvanklik 'n effens negatiewe gevoel teenoor BCIF ervaar, wat oor verskeie sessies verbeter het tot 'n algehele, positiewe reaksie. Ten slotte, die sleutelbord-en-muis kombinasie verskaf veel meer effektiewe en doeltreffende beheer, met een uitsondering, naamlik die Peregrine-handskoen se vinnige opdrag-aktivering, waar die twee koppelvlakke goed vergelyk het. Daar is gevind dat die bestaande vaardigheid en aanvaarding van rekenaar-gebruikers met die tradisionele koppelvlak-kombinasie 'n groot struikelblok in die weg van NUIs is. Gevolglik moet meer effektiewe en doeltreffende beheer as dit wat reeds bereikbaar is met die sleutelbord-en-muis kombinasie gelewer word vir individue om meer natuurlike koppelvlakke te aanvaar en te gebruik.
Dissertation (M.Sc. (Computer Science and Informatics))--University of the Free State, 2015
Keywords: Computer games; Computer science; Entertainment computing; Human-computer interaction