ADAMS避免出错的设置求解器.doc

ADAMS求解器设置//hill711WARNING: The corrector has not converged after 1 attempts. No. of iterations = 6.ERROR: The simulation is terminating at time = 7.53906E-03. Adams can not solve the equations of motion because the mechanism has locked up. At least one constraint can no longer be satisfied. Adams is unable to satisfy the constraint for: JOINT model_1.JOINT_3 .ERROR: Lockup detectedSolver Setting-EquilibriumAdams/Car 2010-04-16 20:31:16 阅读89 评论0 字号：大中小 针对静平衡求解过程中出现Lock Up问题的解决方法ErrorSpecifies the maximum relative displacement error allowed during static simulations.The default is 1.0E-04 and the range is Error 0定义静平衡求解过程中的位移相对误差；此数值越大求解越容易收敛，自然误差也越大。TlimitSpecifies the maximum translational increment allowed per iteration during static simulations performed using static simulations.The default is 20 and the range is Tlimit 0定义静平衡求解过程中，每一步迭代的最大位移增量；对于复杂模型，若位移增量过大，受力的突变会导致静平衡求解失败；AlimitSpecifies the maximum angular increment allowed per iteration. The default units for Alimit are radians. To specify Alimit in degrees, add a D after the value.The default is 0.17453 (10 D) and the range is Alimit 0与Tlimit相似，需要注意的地方是默认单位是“弧度”，若需要输入“度”，必须在数值后面加“D”。如需要设置为10度，输入为10DMaxitSpecifies the maximum number of iterations allowed for finding static equilibriums.The default is 25 and the range is Maxit 0.最大迭代步数，应该与Tlimit和Alimit配合设置；假设初始状态与平衡状态的位移相差100mm，而Tlimit设置为1，则Maxit需要设置比100大，设置为200应该差不多了。StabilitySpecifies the fraction of the mass and damping matrices ADAMS/Solver adds to the stiffness matrix. Adding a fraction of the mass and damping matrices to the stiffness matrix can stabilize the iteration process and prevent the iteration from diverging. Often the stiffness matrix is singular for a system because the system is neutrally stable (for example, the system moves in certain directions without affecting the potential energy). Adding a fraction of the mass and damping matrices to the stiffness matrix removes this singularity and makes it possible to solve for equilibrium positions. The value of Stability does not affect the accuracy of the solution, but it does affect the rate of convergence of the iteration process.The default is 1.0E-05 and the range is Stability 0.施加于刚度矩阵的一个“稳定系数”，使迭代过程更加平稳，更容易收敛；此数值不影响求解精度，理论上越大使迭代越容易收敛，但越大会使求解越慢。ImbalanceSpecifies the maximum force imbalance allowed during static simulations performed using static analyses.The default is 1.0E-04 and the range is Imbalance 0.个人理解为与ERROR是相类似的，此处为力的误差;此数值越大求解越容易收敛，自然误差也越大。以上各数值，ERROR、Imbalance对求解精度是有影响的，不宜设置过大；.Error、Imbalance设置越小，Tlimit、Alimit需要设置得越小，Maxit需要设置得越大，求解时间越长；Tlimit、Alimit与Maxit要配合使用；Stability根据实际情况设置；Maxit影响求解失败前的求解次数，Stability影响求解速度。正确的设置，可以在效率与精度之间得到一个平衡点！以下是个人对静平衡求解过程的非专业理解：下图是带有前、后板簧的卡车求解设置参考：问题：我的adams仿真时出现“exception 11 detected”，然后就退出了，这是怎么回事，我以前装过一个adams的版本然后卸了又装了adams2005，是不时这个原因，哪位高手能给指点一下数据太大了，系统异常造成的应该将adams/2005里的dformd.dll拷贝到windows/system32/