GruntSim Program (IMAGE) Office of Naval Research Caption A Marine tests the ETOWL, a 3-D computer simulation program geared toward lightening warfighter equipment loads. (Photo courtesy of the University of Iowa.) Credit Courtesy of the University of Iowa Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.