健康等级不同的装备在维护保养和执行任务时应采取不同的方案。当前装备的测试评估仍然采用“是非制”，即通过测试仅能判定装备正常与否，缺少对其健康等级的评判。针对这个问题，以某伺服机构为研究对象，提出一种基于改进证据理论的健康状态评估方法,该方法首先确定能够全面表征伺服机构健康状态的参数集合，利用归一量化的方法对测试数据进行处理。然后基于改进的证据理论，对处理后的各项参数隶属度进行融合，从而得到伺服机构的健康状态等级。最后，通过对某伺服机构的实例分析，验证了所提方法的有效性和应用价值。

Different solutions of maintenance and operation should be taken for equipment at different health levels.The current testing and evaluation of equipment is still realized by the “true or false” method,which can only describe whether the equipment is normal or not,and the health level can't be evaluated.Aiming at this problem,a health status assessment method based on improved evidence theory is proposed,taking a certain type of servo mechanism as the research object.Firstly,a set of parameters is proposed to represent the health of the servo mechanism comprehensively,and a normalization method is used to process the test data.Furthermore,the membership of each processed parameter is fused based on the improved evidence theory,and thus the health status level of the servo mechanism is obtained.Finally,the proposed method is verified by the case study to a certain servo mechanism.It is demonstrated that the proposed method is valid,with certain application value.