OptiStruct Error #2866

Dear all,

I want to use measured and filtered acceleration data in the time domain as an excitation load for a model in Squeak & Rattle Director. Therefore, the data have been processed using MATLAB and then have been stored as a .csv file. Furthermore, the sample rate and cutoff frequencies have been adopted to Hyperworks its resolution (100 Hz sample rate, 50 Hz cutoff because of Nyquist theorem & values rounded to 2nd decimal place). 

The import of the data works fine and the plots look as expected. There are no discontinuities at TABLED1 endpoints.

However, when running OptiStruct Solver, the Error #2866 occurs (see below). 

Unfortunately, I cannot find this error code in ALTAIR OptiStruct's error message database (to be accessed via Error Message Database (altair.com)). Also, the error message does not provide information that help me with resolving the error.

There is no issue with the model itself as I am working with the official SnRD test model from ALTAIR and the solver worked well with other input signals.

It would be highly appreciated if someone can explain to me what causes the error described and how to solve with it. 

Thank you so much in advance. 

Best, Fabian 

Error Message: 

************************************************************************

 A fatal error has been detected during input processing:

  *** ERROR # 2866 ***
  GPFORCE/SPCFORCE/MPCFORCE output is requested for a modal dynamic
  solution. The model has rigid equations and the solution process
  requires multiple eigensolutions. This is not supported in the
  current version.

 *** Run terminated because of error(s) in the input data.

************************************************************************

 ==== End of solver screen output ==== 

 ==== Solver FAILED ==== 

 ==== OptiStruct Job completed ====