The range of rotation (RoR) in a knee exoskeleton is a critical factor in rehabilitation, as it directly influences joint mobility, muscle activation, and recovery outcomes. A well-designed RoR ensures that patients achieve near-natural knee kinematics, which is essential for restoring gait patterns and preventing compensatory movements. This paper presents optimal design of one degree of freedom knee exoskeleton. In kinematic analysis, the existing design being represented by nonlinear and nonconvex mathematical functions. To obtain feasible and optimum measurement of the links of knee exoskeleton, an optimization problem is formulated based on the kinematic analysis and average human's leg measurement. The optimized solution increases the range of motion of knee exoskeleton during sit to stand motion by $24 \%$ as compared with inspired design. Furthermore, misalignment study is conducted by comparing the trajectory of human's knee and exoskeleton's knee during sit to stand motion. The joint movement is calculated using marker and camera system. Finally, a prototype of the knee joint exoskeleton is being developed based on optimal dimensions which validate the maximum range of motion achieved during simulation.

翻译：膝关节外骨骼的旋转范围（RoR）是康复治疗中的关键因素，因为它直接影响关节活动度、肌肉激活和恢复效果。一个设计良好的RoR能确保患者实现接近自然的膝关节运动学，这对于恢复步态模式和防止代偿性运动至关重要。本文提出了一种单自由度膝关节外骨骼的优化设计。在运动学分析中，现有设计由非线性非凸数学函数表示。为获得膝关节外骨骼连杆的可行且最优尺寸，基于运动学分析和平均人体腿部测量数据构建了优化问题。优化方案使膝关节外骨骼在坐立动作中的运动范围比参考设计提高了$24\%$。此外，通过比较人体膝关节与外骨骼膝关节在坐立动作中的轨迹进行了对位偏差研究，关节运动通过标记点与摄像系统计算。最后，基于优化尺寸开发了膝关节外骨骼原型，验证了仿真中实现的最大运动范围。