This chapter presents the development, modeling, and analysis of a multi-segment mechanism for a hand rehabilitation exoskeleton driven by a single layer of steel spring, capable of assisting both the extension and flexion of the fingers in alignment with natural human finger motion patterns. The multi-segment mechanism's inherent simplicity and flexibility enhance the device's overall performance, while its compliance ensures safety for human-robotic interaction. Furthermore, a tau-jerk motion planning approach, coupled with an exoskeleton finger structure optimization method, has been incorporated into the design and control system to ensure the exoskeleton’s finger movements closely mirror human finger motions. Experimental results demonstrate that the hand motions generated by the exoskeleton, using our proposed tau-jerk motion planning method, exhibit superior conformity to human finger motions compared to commonly used methods, such as cubic polynomial interpolation and 3-4-5 polynomial interpolation for hand rehabilitation exoskeleton design.