private void placeForceFieldGenerators() {
		while (getElementCoverage(ForceFieldGenerator.class) < COVERAGE) {
			final Position randomPos = getRandomPosition();
			final ForceFieldGenerator forceFieldGen = new ForceFieldGenerator(grid);
			if (grid.validPosition(randomPos) && canHaveAsElement(randomPos, forceFieldGen)) {
				grid.addElementToPosition(forceFieldGen, randomPos);
				forceFieldGen.generateForceField();
			}
		}
	}