求助:我在做结构分析时遇到这样一个错误:The value of UX at node 1062 is 516486315. It is greater than the <BR> current limit of 1000000. This generally indicates rigid body motion <BR> as a result of an unconstrained model. Verify that your model is <BR> properly constrained. <BR>采用的是shell63和solid45两个单元,帮我看看是什么原因,如果全用solid45就没什么问题 <BR>