Intertwined Digital Human and Robot Modeling-Driven Development of Reharob 3.0: The Quad-Arm Functional Upper Limb Rehabilitation Robot System

Mass-produced industrial and service robots have been used to build therapeutic rehabilitation robots since the 1990s. REHAROB 1.0, the dual-arm upper limb rehabilitation robot prototype, was among the pioneers. The industrial collaborative robot is a new type of robot in terms of safety, appearance, performance, and cost, thanks to which it is proving itself in more and more applications. To take advantage of these benefits, the REHAROB 3.0 Robotic Trainer for Activities of Daily Living, also updated in its name, was designed and built using two industrial collaborative robots and two uniquely developed robotic fingers. The goal of our study was to introduce an iterative design and simulation process in which digital human modeling is intertwined with digital robot modeling, leading to an upper limb rehabilitation robot system targeting outstanding performance features such as synchronous exercising of every upper limb anatomical joint and training reaching and grasping Activities of Daily Living with real objects in a real environment.