This book offers a timely report on an emerging topic in the field of wearable assistive technology: the design and development of robotic extra fingers. After a concise review of the state of the art and a description of earlier prototypes, it discusses the authors' efforts to address issues such as portability and wearability of the devices, including strategies to reduce fatigue and to integrate the motion of the extra fingers with that of the human hand. The book also explores optimized control algorithms and the design of wearable sensorimotor interfaces, and presents a set of tests carried out on healthy subjects and chronic stroke patients. Merging concepts from robotics, biomechanics, human factors and control theory and offering an overview of supernumerary robotic fingers, including the challenges, this book will inspire researchers involved in the development of wearable robotic devices and interfaces based on the principles of wearability, safety, ergonomics and user comfort.

Autorentext
** Dr. Hussain** is an assistant professor in Mechanical Engineering department at Khalifa University (KU), Abu Dhabi, UAE. He received his PhD degree in robotics from University of Siena, Italy. His research interests include Supernumerary (Extra) Robotic limbs, Medical Robotics, Soft Robotic hands, Complaint Manipulators, Exoskeletons and prosthesis.

**Prof. Prattichizzo** is a professor of robotics at the University of Siena, Siena, Italy, and since 2009 he is a Scientific Consultant at Istituto Italiano di Tecnoloogia, Genova, Italy. In 1994, he was a Visiting Scientist at the MIT AI Lab. He received the Ph.D. degree in robotics and automation from the University of Pisa, Pisa, Italy, in 1995. His research interests are in Supernumerary (Extra) Robotic limbs, haptics, grasping, visual servoing, mobile robotics and geometric control.

Inhalt
Introduction.- Enhancing human hand manipulation abilities through supernumerary robotic ngers.- Compensating hand function in chronic stroke patients through the supernumerary robotic nger.- Design and development of soft supernumerary robotic ngers for grasp compensation in chronic stroke patients.- Wearable sensory motor interfaces for supernumerary robotic ngers.- Wearable EMG interfaces for motion control of supernumerary robotic ngers.- From grasp compensation towards hemiparetic upper limb rehabilitation.- Conclusions and future work.