Common Simulation Error Messages

Message

Meaning

Possible Solution/Problem

Failed to reach convergence in 25 iterations on assembly displacement.

ADAMS/Solver cannot determine the assembled position.

• Check for inconsistency in the constraints.

• Check for redundant constraints.

• Increase the maximum number of iterations (for example, to 25) in ADAMS/Solver parameters dialog box.

The Initial Conditions displacement solution failed due to a position that produced a singular matrix.

ADAMS/Solver is unable to determine the assembled position because the step size has become too small.

• Constraints exist in the model that are nearly redundant.

• There is excessive penetration between parts with contact or impact functions.

The Kinematic Displacement solution failed to converge after executing %d iterations. For the last attempted iteration the equation with the largest error was %s Error = %E. The variable receiving the largest increment was %s Delta = %E.

ADAMS/Solver is unable to determine initial position of mechanism.

• Check to see if the model is in a locked position.

• Check for inconsistencies in the constraints.

• Check for redundancies in the model.

At time %E the Kinematic Displacement solution matrix is singular. The Kinematic solution cannot proceed.

The step size used to determine the next point in time has become too small.

• Check to see if the model has reached a locked position.

• Check for redundant constraints; ADAMS/Solver may have removed the wrong constraint and caused the model to become inconsistent.

At time %E the model has %d degrees of freedom. The Kinematic solution cannot proceed.

The simulation started as a Kinematic system and during redundancy removal it has become dynamic

• Check for redundant constraints; ADAMS/Solver may have removed the wrong constraint and caused the model to become inconsistent.

At time % E in the Kinematic Displacement solution, a redundant constraint has become inconsistent.

ADAMS/Solver cannot satisfy all the constraint equations due to a conflict in the constraints.

• Check for redundant constraints; ADAMS/Solver may have removed the wrong constraint and caused the model to become inconsistent.

At time %E the GSTIFF integrator is unable to proceed. Corrector convergence could not be achieved. The size of the last attempted time step: %E State variable with maximum value: %s %E State variable with maximum derivative: %s %E

ADAMS/Solver is unable to determine the next time step.

• The step size has become too large and is unable to determine the next solution in the simulation.
  
  Suggested solution: Limit the maximum step size permitted by ADAMS/Solver by changing the maximum time step in the Simulation Settings dialog box. A typical change would be from 1 to 0.1 or 0.01.

At time %E the acceleration and force acceleration solution failed to converge after executing %d iterations. For the last attempted iteration the equation with the largest error was %s Error = %E. The variable receiving the largest increment was %s Delta = %E.

A rapid change in force/acceleration has occurred, and ADAMS/Solver cannot determine the next time step (there is discontinuous motion).

• Check mass and inertia properties to ensure they are valid.

• Make sure the motion generators are valid.

• Check to see if part contact or impact functions have caused a strange response in the model (verify properties).

At time %E the Jacobian matrix for the GSTIFF corrector is singular.

The time step size has become too small.

• The system includes a zero (or relatively small) mass on a part with an unconstrained translational degree of freedom.
  
  Suggested solution: Make sure you have mass on all parts with translational degrees of freedom.

• The system includes a zero (or relatively small) inertia on a part with an unconstrained rotational degree of freedom.
  
  Suggested solution: Make sure you have inertias on all parts with rotational degrees of freedom.

• The system has become over constrained. That is, the number of degrees of freedom has decreased, and the mechanism may be locked.
  
  Suggested solution: Look carefully at the display of the system configuration at the time of the singularity to see if a lock up occurred.

• The integration step size has become too large or too small. When you use the GSTIFF integrator, the solution process involves dividing the mass matrix by h. If the step size has become too large or too small, this may cause the Jacobian matrix to become ill conditioned.
  
  Suggested solution: Use the HMIN or HMAX arguments in the .adm file to affect the integration step size. Or, change the number of output steps (which may also affect the integration step size).