Aiming with Assistance: Player Balancing for Differences in Fine Motor Ability

Abstract

A significant barrier to players’ enjoyment of video games is the competitive nature of many multiplayer games. It can be difficult for people with different abilities to enjoy playing together. Player balancing (such as aim assistance) helps people of varying abilities play together by adjusting game mechanics. Player balancing is particularly important in games where differences in fine motor ability can have large impact on game outcomes, and in making games accessible to people with motor disabilities. The focus of this thesis is to determine whether aim assistance can reduce the barriers to group play with children who have cerebral palsy. We did this by evaluating whether aim assistance significantly reduces differences in player performance, and whether aim assistance negatively affects player perceptions of fairness and fun. Our evaluation involved a two-step process. The first step was a six-day study of a novel aim assistance algorithm with eight children with cerebral palsy. We tested the impact of this algorithm on balancing, player behaviour, and player perceptions through its incorporation in a two-player competitive aiming game. Our second step involved a qualitative evaluation with 18 pairs of typically developed adults of a revised game that implemented two improvements to the aim assistance algorithm. Our aim assistance algorithm did not significantly reduce the gap in player performance in a video game for children with cerebral palsy. However, it did reduce the difference in players’ scores in heavily imbalanced (“blowout”) games between players with different levels of fine motor ability levels. Aim assistance was generally viewed positively in social play settings and, players reported it had a positive impact on their play experience. We also found that game elements that draw attention to aim assistance need to be designed with attention to colour. When applying visual effects, players need to be informed of their purpose to make use of them effectively.