Have you ever had to make a mad dash for a train or plane only to be slowed down by the two – wheeled suitcase you were pulling as it lurches violently from side to side or even topples over? If so read on, for scientists in France have carried out a study on this very problem and believe they have come up with two solutions: solution number one – rather than slow down, speed up; solution number two – keep the handle of the suitcase close to the ground, the closer the better. To come up with this advice, the team observed a suitcase on a treadmill to find out what causes the uncontrollable rocking. They then came up with equations on why the bags rock from one wheel to the other. They found that when a suitcase starts wobbling after hitting a bump it either falls over or gets to the point where it swings regularly from side to side. If this occurs, the swinging effect can be reduced by moving faster. As the team explained, “Thus, one should accelerate rather than decelerate to attenuate the amplitude of oscillations. A non-experienced suitcase puller would not react this way. The outcome should not be a dramatic for a suitcase, but it could be troublesome for a trailer towed by a vehicle.” Sounds like an open and shut case.