Surface stimulation is a non-invasive method of muscle activation which uses adhesive electrodes placed on the surface of the patient skin above the location of the desired muscles to be activated. One application is in stroke rehabilitation where a controller is used to provide assistive stimulation to a patient completing a finite duration task with the impaired limb. Effectiveness of treatment is strongly related to the precision and accuracy of the stimulation applied, and the feasibility of advanced control approaches has been established in two recent clinical trials using iterative learning control algorithms. Commercially available large surface electrodes are not suitable for precise control of the hand and wrist due to their weak selectivity and simultaneous activation of several opposing muscles. An alternative is the use of electrode arrays where individual array element selection enables more precise control of muscle activation. Locating the optimal stimulation sites is critical to the effective application of surface electrode array stimulation and this paper develops a method for optimal selection of the stimulation sites. To overcome practical difficulties the method utilises the concept of 'Virtual Elements'.
展开▼
