足式机器人在行走过程中，足端与地面之间的法向冲击力将影响机器人的在垂直方向上的稳定性。被动柔顺可以减小垂直冲击力但同时可引发平台持续震荡。针对该问题，设计基于足端力反馈的主动柔顺控制器，分析其对机器人垂直稳定性的影响。机器人由于机械间隙、步态、路面等因素将出现足端打滑现象，导致机器人水平方向失稳。引入摆腿回缩技术，分析摆腿回缩对机器人水平稳定性能的影响。仿真和液压足式机器人行走试验验证提出方法的有效性，提高了机器人行走过程中的垂直和水平方向稳定性。

Impact force between leg and terrain will have influence on the vertical stability of legged robots. Although passive compliance can decrease the impact force,it will bring side effects such as body vibration. To deal with it,a force feedback based active compliance controller is proposed,and its influence on the vertical stability is analyzed. Meanwhile,due to mechanical clearance,gait pattern,and terrain parameters,foot slippage may occur and then causes stability issues. Swing leg retraction is then introduced and analyzed to improve the horizontal stability of legged robots. Simulations and experiments show the effectiveness of the proposed methods and the enhancement of vertical and horizontal stability.