Method for shifting natural frequencies of damped mechanical systems

A method for shifting the natural frequency of a damped mechanical system to a desired value is discussed. The solution is derived from the force response equation of the original system. The final equation contains only the degrees of freedom connected to the modifying parameter. Iterations are required, but the solution converges rapidly. Modal coupling effects and sensitivity for shifting a frequency are also derived. Numerical results indicate that the method is effective for system dynamics modification. (Author)