In the application of the exoskeleton arm, nonlinear inertial forces impact mechanical transparency and degrade control performance. To reduce these effects, a dynamic decoupling technique is employed to linearize the dynamics of 2-DOF exoskeleton arms. Incorporating an epicyclic gear train provides a means of optimally redistributing kinetic energy, thus contributing to linearizing and decoupling the system’s dynamic behavior. Furthermore, a minimum jerk trajectory is implemented for motion generation, effectively minimizing the variations in actuating forces. To ensure precise motion tracking and high energy efficiency, a linear controller with simple structure is applied. The suggested design methodology is illustrated by simulation, demonstrating its effectiveness in improving overall control performance.