  Rehabilitation exercises performed by children with cerebral palsy are
tedious and repetitive. To make them more engaging, we propose to use an
exergame approach, where an adaptive application can help the child remain
stimulated and interested during exercises. In this paper, we describe how the
mobile phone sensors can be used to classify wrist movements of the user during
the rehabilitation exercises to detect if the user is performing the correct
exercise and illustrate the use of our approach in an actual mobile phone
application. We also show how an adaptive difficulty system was added to the
application to allow the system to adjust to the user. We present experimental
results from a pilot with healthy subjects that were constrained to simulate
restricted wrist movements, as well as from tests with a target group of
children with cerebral palsy. Our results show that wrist movement
classification is successfully achieved and results in improved interactions.
