A system for automatic model verification and validation

The increasing use of digital computers in the simulation of dynamic systems presents a number of new problems. In particular, the inclusion of a digital computer in a predominantly analog environment introduces time base problems. The digital computer appears to the analog circuitry to be a particular pulsed filter. Time delays due to sampling, computation, and output appear dynamically as ideal transportation delays.The effects of time delays1 can be compensated for at the digital-to-analog or analog-to-digital interfaces by either analog2 or digital lead filters. Considerations with respect to problem constraints and the available equip ment dictate where and by what means the compensation is to be mechanized. Problem constraints involve the num ber of variables to be interfaced, the characteristics of the variables to be predicted (i.e., not highly nonlinear or dis continuous) and the effects of prediction errors on the variables. Digital simulation of a system of equations usu ally results in a highe...