<p>This study presents the design and prototyping of an active knee orthosis to assist rehabilitation process through the controlled flexion-extension of the joint. 3D scanning and additive manufacturing to create a personalized and lightweight device was used. A dynamic analysis to evaluate the forces and torques acting on the orthosis during movement was conducted. Also, finite element simulations to ensure the mechanical integrity of critical components under certain loads. The manufacturing process included the use of 3D-printed components and a mechanical braking system to adjust the range of motion. Preliminary testing confirmed the orthosis’s ability to support the flexion and extension of the device from 0 to 140 degrees. These findings demonstrate the potential of digitally manufactured orthoses to provide customized and effective solutions for lower limb rehabilitation.</p>