Conventional physical therapy is often limited by the need for continuous one-on-one supervision and a lack of engaging, interactive exercises, which can lead to a loss of motivation, especially in children. To overcome these challenges, RoboRehab2D was developed as a budget-effective, two-dimensional upper-limb rehabilitation system. Utilizing a planar, five-linkage mechanism, the robot provides a motivating, game-like environment that supports both passive and active therapy tailored to a patient’s specific recovery stage. It enables precise, repeatable exercises like reaching and tracing while seamlessly supplying therapists with objective data to monitor performance.

Beyond its clinical benefits, RoboRehab2D stands out for its accessible, open-source design and clever engineering. The system uses low-cost servo motors and an admittance-based control strategy to ensure compliant human-robot interaction, impressively estimating torque directly from servo currents to eliminate the need for expensive external force sensors. By making its mechanical, electronic, and software designs freely available, the creators aim to foster global collaboration and innovation. Ultimately, this transparency makes advanced, data-driven pediatric and home-based rehabilitation significantly more affordable and accessible to clinics, researchers, and families worldwide.