The work presented here suggests new ways to tackle exergames for physical rehabilitation and to improve the players’ immersion and involvement. The primary (but not exclusive) purpose is to increase the motivation of children and adolescents with severe physical impairments, for doing their required exercises while playing. The proposed gaming environment is based on the Kinect sensor and the Blender Game Engine. A middleware has been implemented that efficiently transmits the data from the sensor to the game. Inside the game, different newly proposed mechanisms have been developed to distinguish pure exercise-gestures from other movements used to control the game (e.g., opening a menu). The main contribution is the amplification of weak movements, which allows the physically impaired to have similar gaming experiences as the average population. To test the feasibility of the proposed methods, four mini-games were implemented and tested by a group of 11 volunteers with different disabilities, most of them bound to a wheelchair. Their performance has also been compared to that of a healthy control group. Results are generally positive and motivating, although there is much to do to improve the functionalities. There is a major demand for applications that help to include disabled people in society and to improve their life conditions. This work will contribute towards providing them with more fun during exercise.
For a number of years, the possibility of applying serious games for rehabilitation purposes has been thoroughly investigated [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28]. It is often claimed that serious games reduce health system costs and efforts as they enable in-home rehabilitation without loss of medical monitoring, and in so doing provide an additional fun factor for patients [22,23,24]. Multiple reviews have summarized the very powerful contributions and reveal that the systems are generally evaluated as feasible, but no state of general applicability has yet been reached [2,3,5,7,11,13].
Most studies are quite specialised and tend to cover the same groups of largely elderly patients (e.g., stroke and Parkinson’s), which do not constitute a credible target group per se for gaming among the population. In addition, the impression is that the same functionalities are being tested repeatedly, without any evolution. Above all, other groups like children and adolescents with chronic diseases are rarely addressed, even though they are an excellent target group and would probably benefit greatly from using exergames as they need to move like any other child but are mostly limited to performing their exercises with a physiotherapist. This is generally boring, time-consuming and prevents them from playing with friends during this time. If instead they could play games involving physical exercises, without it feeling like rehabilitation, due to proper immersion and motivation, they would possibly need fewer sessions with the therapist, which may in turn improve their social life. Commercially available games would be good enough for many children with physical disabilities, if only they were configurable and adaptive to their potential and needs. Remote controls (RC) are typically not sufficiently configurable (button functions cannot be changed or the RC cannot be used with one hand) and are only made for hands (why not for feet or the mouth?) Some RCs are not sufficiently precise in detection, and so the user ends up tired and loses motivation. Motion capture devices like the Kinect sensor seem to provide better prerequisites for exergaming purposes but feature important limitations too, (e.g., detection of fine movements and rotations) such that the needs of many people are still not be covered by commercial solutions.
However, this is not due to the sensors, but rather the software, which lacks configurability for special needs, such as simple adjustments of level difficulties or the option of playing while seated. For the latter, some Kinect games are available , but those are hardly the most liked ones, as has been stated by affected users . Therefore, more complex solutions are required to adapt a game to problems like muscle weaknesses (most games require wide or fast movements), spasticity (“strange” movements are not recognized) or the available limbs (for instance configuring a game to be controlled with the feet for players without full hand use).
To fill these gaps, the authors of the work presented here are pursuing the overall aim (as part of a long-term project) of creating an entertaining exergaming environment for adventure games that immerses the players into a virtual world and makes them forget their physical impairments. Knowledge of the gaming industry is applied to create motivating challenges that the users have to solve, which are sufficiently addictive to make the exercises pass to an unconscious plane. The gaming environment is configurable to the user’s potential and requirements. Challenges will be programmable by a therapist and will also adapt themselves to the players automatically real-time, by observing their fatigue or emotional state (lowering the difficulty or switching to more relaxing exercises when needed)…
Figure 8. Different scenes while the volunteers were playing. (a) “The Paper-Bird”, (b) “The Ladder”, (c) “The Boat” and (d) “Whack-a-Mole”.