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Digital Debunking: Is There A Technique to the Tablecloth Trick?

Now that the classic film reboot “Ghostbusters: Afterlife” has hit our screens, many of us have been reminiscing about the original Ghostbusters, recalling fondly the memorable quotes, special effects, and the countless moments of laughter throughout the movie. Most will remember the ballroom scene, where almost everything is damaged as the main characters wrangle with Slimer (a.k.a Onionhead). However, not before Dr. Peter Venkman decides to try and recreate the well-known tablecloth trick.

After smashing everything but the flowers on the table, he cheerfully shouts, “And the flowers are still standing!” Who you gonna call?! Someone to clean up this mess preferably…

Dr. Venkman didn't quite get it right...

Always enticing to try, many have performed the tablecloth trick successfully (and, probably, more have tried it unsuccessfully) and there certainly seems to be a knack to it. Many factors come into play for a successful ‘pull,’ including the speed and angle the cloth is yanked from the table. Using the Altair simulation tools stored in our proton pack, we put this trick to the test to discover what determines a successful yank.

Laying the table

To dig deeper, we used  Altair® Radioss®, our leading analysis solution designed to evaluate and optimize product performance for highly nonlinear problems under dynamic loadings. Used across numerous industries around the globe, it improves the crashworthiness, safety, and manufacturability of complex designs. Dynamically speaking, the whip of a tablecloth is a surprisingly complex movement. By utilizing Radioss, we can better understand the complex motions and loads exhibited. Our approach was to perform simulations that both passed and failed, determined by the locations of the tableware pre and post whip. If any of the tableware items fell over or off the table, the attempt was deemed a failure. Before any of this could happen however, we needed to lay the tablecloth.

Simulation of the tablecloth falling onto the table

A powerful feature of Radioss is that it can save the results of previous analyses and use the resultant data as inputs for subsequent ones. Utilizing this feature, we separated our approach into two phases. First, we simulated the tablecloth falling onto the table under gravity alone to collect the resultant data. Secondly, the final state of the settled cloth was recorded and used in the whip analysis.

As mentioned earlier, many factors influence the outcome of this trick. Different levels of friction, the velocity pattern of the pull, and the direction at which the tablecloth is pulled at all impact the result.

As you can see from our results, we performed a successful tablecloth pull! Comically, we also achieved a result like Dr. Venkman’s.

Our results showed how, and how NOT to perform this trick

From our simulations, we learned the key to a successful whip is perfecting the angle. As you can see from the videos below, in the failed attempt, the tablecloth gets pulled at an upward angle and with a twist so that it passes the side of the ‘puller.’ This is the mistake Dr. Venkman makes in the ballroom scene.

Our simulations from a bird’s eye view...

...and from the side

To add the final Hollywood touch, we rendered our simulations using Altair® Inspire™ Studio, our all-in-one industrial design solution. Inspire Studio is the new solution for innovative designers, architects, and digital artists to create, evaluate, and visualize designs faster than ever before. With unrivalled flexibility and precision, its unique construction history feature, combined with multiple modeling techniques, empowers users throughout the creative process.

Without the right technique, tableware gets sent flying...

...but with the right technique -- success!

As it turns out, there is a technique to the tablecloth trick. Pulling the cloth at an angle slightly lower than the table and straight towards you yielded the best results. Someone should let Dr. Venkman and the rest of the Ghostbusters team know. Better yet, let the stars of the new Ghostbusters film know in case they find themselves in a similar predicament.