为有效评估并控制无人机（unmanned aerial vehicle, UAV）运行风险，在总结无人机地面撞击各种风险因素的基础上，分析无人机地面撞击可能的发生原因，确定相应的控制措施，建立风险分析与控制技术相结合的安全屏障模型，可清晰地显示无人机运行安全致因、缓解措施以及事故后果之间的逻辑关系；进一步将蝴蝶结（bow-tie, BT）模型映射到贝叶斯网络（Bayesian network, BN），量化BT模型中各要素，计算不安全事件发生的概率。结果表明：该模型能够清晰地展现风险控制过程并有效降低无人机运行风险，为无人机运行风险评估与控制提供了一种高效、实用的方法。

In order to effectively evaluate and control the operational risks of unmanned aerial vehicle (UAV), based on the summary of various risk factors of UAV ground impact, the possible causes of UAV ground impact were analyzed, corresponding control measures were determined, and a safety barrier model combining risk analysis and control technology was established. It can clearly display the logical relationship between the causes of UAV operation safety, mitigation measures and accident consequences. Bow-tie(BT) model was mapped to Bayesian network (BN), each element of BT model was quantified, and the probability of unsafe events was calculated. The results show that the model can clearly show the risk control process and effectively reduce the operational risk of UAV. It provides an efficient and practical method for the operational risk assessment and control of UAV.