The transmission error of cable-driven sheaves (CDS) used in space docking locks directly affects the synchronous docking of two spacecraft, which is guaranteed mainly by the preload applied to their serial cables. But it is difficult controlled precisely because of the complicated cable deformation and operating conditions. The synchronous testing efficiency of the docking locks is inevitably influenced, correspondingly. This paper proposes a prediction model for the transmission error of CDS based on their cable deformation. In this model, the deformations of non- and free sectional cables are both modified on finite element analysis, which are respectively derived from classical Capstan equation and Hooke’s law for them without considering the effects of the friction coefficient between wire strands. Based on the proposed model, the relationships between the transmission error and dominating factors are analyzed. Then the preload compensation for transmission error is obtained at the engaging and locking angles of the docking locks, respectively. Experiments validate the model. This can provide a valuable reference in controlling the transmission error of CDS and improving the assembly efficiency of docking locks.

空间对接锁定装置中使用的电缆驱动槽轮（CDS）的传输误差直接影响两个航天器的同步对接，这主要是通过施加在其串行电缆上的预载来保证的。但是由于复杂的电缆变形和操作条件，很难精确控制。不可避免地会影响对接锁的同步测试效率。本文基于CDS的电缆变形提出了CDS传输误差的预测模型。在该模型中，对非截面电缆和自由截面电缆的变形都进行了有限元分析，并分别从经典的Capstan方程和胡克定律推导出来，而没有考虑线束之间的摩擦系数的影响。根据建议的模型，分析了传输误差与主导因素之间的关系。然后，分别在对接锁的啮合角度和锁定角度获得传动误差的预紧补偿。实验验证了该模型。这可以为控制CDS的传输错误和提高对接锁的组装效率提供有价值的参考。