1. Rehabilitation and Assistive Technology Group, School of Health and Related Research, University of Sheffield, Sheffield, UK,
2. Adaptive Systems Research Group, School of Computer Science, University of Hertfordshire, Hatfield, UK,
3. Rehabilitation and Assistive Technologies Group, School of Health and Related Research, University of Sheffield, Sheffield, UK,
4. Roessingh Research and Development, Enschede, the Netherlands,
5. Department of Mechanical Engineering, University of Twente, Enschede, the Netherlands,
6. IRCCS San Raffaele Pisana, Rome, Italy, and
7. Adaptive Systems: Assistive and Rehabilitation Robotics Laboratory, School of Computer Science, University of Hertfordshire, Hatfield, UK