Adjustability for grasping force (AGF), which is one of motor function of fingers, is an ability to grasp an object with appropriate force. Since a person with a disable hand can not adjust grasping force, he/she grasps an object with extra force or can not grasp it due to lack of grasping force. In our previous study, we developed a training and testing device of the AGF, which is called iWakka. In this paper the usefulness of training and testing with iWakka was confirmed by applying CI+i therapy to ten hemiplegic patients after stroke. The AGF of all patients was improved after training with CI+i therapy. CI+i therapy was developed by the fourth and fifth authors by adding the training task with iWakka to CI (Constraint Induced Movement) therapy.
