@Test
public void testAdvanceTimeFalling() {
double[] initialPos = log1.getPosition();
log1.advanceTime(0.1);
assertTrue(initialPos[2] > log1.getPosition()[2]);
assertEquals(initialPos[0], log1.getPosition()[0], 0);
assertEquals(initialPos[1], log1.getPosition()[1], 0);
}
public void testAdvancerTimeNotFalling() {
double[] initialPos = log2.getPosition();
log2.advanceTime(0.1);
assertTrue(Arrays.equals(initialPos, log2.getPosition()));
}