Tag Archives: pneumatic

Halloween 2018: Tibetan Yeti

The plan was to recreate a Disney World attraction. Not just put on costumes and play It’s a Small World over and over, but create a fully immersive, multimedia walk-through with interactive video projection and animated props. It was to be the greatest Halloween decorating effort to ever exist. Then a computer interface broke and none of it happened.

The plan was conceived of while on vacation several years ago. There is a spot on Expedition Everest at Disney’s Animal Kingdom where the roller coaster stops and an image of a yeti is shown tearing up the track. We recorded a video of the ride and noticed that the yeti image came through pretty well. It was then that we had the thought that if you had the right seat on the train and had a camera set-up with the right lens, one might be able to acquire a copy of the yeti projection.

Fast forward to this year. Camera in hand, we ride through a few times and get the video in question:

Having the video was only a small part of the plan. As in the ride, the video is only a distraction to misdirect the viewer from seeing the big scary surprise moment. For that we would need a seven-foot tall animated yeti.

For the body of the yeti, we cheated and bought a costume. In retrospect, it might have been a better plan to hire some kid to wear the costume and simply jump out of the bushes periodically, but in true Disney style we built a frame to support the costume with pneumatic arm lifts and animated eyes.

The animated eyes gave the yeti life. They would look around and blink just like a real yeti. The eye animation was executed from a Raspberry Pi single board computer separate from the rest of the system, so they would work even if everything else failed.

The rest was lighting, music and staging. With a tent in the yard, Tibetan music playing and fluttering prayer flags, you were supposed to be transported to a hiking camp on the way to climb Everest. However, with all the lighting, video and the yeti movement under computer control, everything was left dark when the computer died.

Ultimately, the plan was probably flawed from the start. We overestimated how many families would have visited Disney World. It seemed like not that many people got the references to Tibet. Presence of the tent just confused people. Most concluded that the theme was “winter camping.” Hard to argue with that.

Mummy’s Curse Puzzle Door of Doom

Seven years ago we had a Halloween party that involved the construction of a life-sized moving sarcophagus and half a dozen mummies. Since these things are just taking up space in the basement, we decided to reuse them this year.  Reduce, reuse, recycle. That’s our motto.

Except (always a dangerous word), we also decided that after last year’s success of adding interactive elements to the display, we would make the trick-or-treaters jump through some sort of hoop, metaphorically speaking.

This lead to re-watching mummy movies and discussing the appropriateness of using live spiders or beetles to make gags more “interactive”. In ancient Egypt, there were always insects or snakes that lived forever to protect the tomb of the Pharaoh. We should have the same, but the important part of the experience is the challenge one has to face before being thrown into the pit full of asps.

The challenge, we decided, would be to make the kids solve a puzzle. The movies always have a puzzle – translate the hieroglyphics, find the hidden lever on the wall, pull the lever – then run like hell when the floor opens up to a pit full of asps. Clearly, some of this idea has merit.

What we decided on was placing four buttons on the door that had to be pressed in order to be granted candy. While there would be hieroglyphics on the door, you wouldn’t need to translate them. You would need only to match the pattern of icons on the door to those on the buttons. A clever person could get it straight away. A determined person could get it within 16 tries.

Here is where we get in trouble. Since the theme is set in a mummy’s tomb, the door, the buttons, and ideally everything else need to be made out of stone. Or something that looks like stone.

In building our sarcophagus, we had learned some things about carving foam and coating the foam with a hard resin. The picture above show the work-in-progress of making the buttons. Each foam button was cast over a 1/9th size steam table pan. The outer surface of the buttons were carved then the Foam Coat product was mixed with sand to create a hard textured surface. The foam could then be slid back over the steel pan to create a durable mount for each button.

Each button was supported by a small pneumatic cylinder. This was done both to provide a pushing mechanism to reset the buttons and to provide some resistance as the buttons are manually pushed in. The air flow out of the cylinders was controlled so that it took some effort to press against a button. This added to the spooky “should I be doing this?” aspect of the gag. It also provided feedback to the control circuit so the sound of scraping stone could be played while the button was in motion.

Once the button was fully seated, a limit switch triggered the sound of a large stone coming to rest with a thud. The control system waited for all buttons to be set, then either played the sound of a door unlocking or the sound of rattlesnakes (it should be noted that we decided not to use real snakes). The buttons were then pushed back out by the air cylinders.

Since the Foam Coat seemed to be holding up, we decided to fabricate the entire door facade with foam. It had a wooden base that allowed the foam to standoff from the actual door far enough to give space for the button mechanism and to clear the door handle which was completely covered. Indeed, the only way to enter the house was for the door to be unlatched from the inside.

We had a bunch of ideas about the reward/penalty nature of the system. Given our time constraints, we didn’t really get much more done than the sound effects. Remember when this was all about reusing props from past years? We had one more goal and that was to make sentinel snakes hiss with waving tongues. It ended up be a subtle detail that was widely overlooked. On Halloween we barely had time to get the mummies out of the basement.

At 8:04 pm, our neighbor sent a text message: “You’ve created a monster!”

At its peak, there were about 100 kids and parents in the street. We had a line of willing participants jammed on the stairs. The wait was exacerbated by our having been merciless. No one got candy unless the the correct combination was set. When the door opened, kids in the front got served, then the door closed to the protests of the screaming children in line behind them.

Forcing people to solve the puzzle was the best thing we could have done. There would have been no fun in gaining reward without accomplishment. Little kids got a thrill out of finding the solution. Older kids appreciated being able to manipulate what would otherwise have been static decoration. Only the parents of toddlers had misgivings. Adults don’t like to be put on the spot.

We learned a lot about human behavior, but some things remain a mystery. Most kids and parents patiently waited their turn. After all, it took only a few seconds to try a combination and there were plenty of people to help. But some people – parents and kids – walked past, stating they didn’t have time.

In conclusion, 207 kids received candy. Maybe 20 were denied. We tried to keep count, but at times things were out of control. The only down side to the whole event was that we had to be constantly vigilant with the opening of the door. Next year, creating a automated candy dispersal system will be a goal.


Halloween 2011: Dia de los Muertos

Dia de los Muertos: The Day of the Dead, as celebrated in Mexico and selected Central American countries. We made it come to life with an exploding piñata and dancing skeletons. Just like they have in Mexico.

The dancing skeletons idea came from a clever bit of animation Ruth found on the web. With an unlimited schedule and budget, it would have been cool to completely re-animate the video in three dimensional form. Since we are not independently wealthy, we decided to create some moving props to go along with the video itself.

In its final form, the video was cut down to a minute and half and projected on the front of the house while three skeletons got to pogo up and down on pneumatic cylinders. To add a bit of shock value to the presentation, a faux case of tequila was set out front to open and snap shut.

Things that amazed us #1: We didn’t see any children get scared by the tequila box, but we scared the crap out of a couple of adults. Maybe the kids expected something to happen. Maybe we just missed seeing it.

With the weather being what it was, we really did not expect a big turn-out. Monday morning, Doug went out to shovel the front lawn only to find that it was frozen solid. Setbacks were anticipated, but this was a new one.

The snow eventually softened-up to the point that it could be scraped off the grass leaving a wet, almost muddy mess combined with water dripping off the roof. With everything this year being either made out of paper or having 110V running through it, or both, we had some serious concerns.

The original plan was to decorate much more fiesta-like. Some of the lighting had to be jettisoned and paper flags remained indoors, but we were able to put down enough plywood to keep things dry. The end result was a bit creepier— fine for Halloween and possibly helpful in integrating our bizarre set-up with our neighbor’s more traditional displays.

Things that amazed us #2: Our neighbors confirmed that this was the second most popular theme we’ve used. The first? Giant Floating Eyeballs. No idea why. Giant Floating Eyeballs isn’t even a theme.

By late afternoon Ruth was able to firmly plant the papier-mâché skeletons in the ground on PVC pipe. El Burro del Diablo had been hung and the skeletons were dancing along to their music video. 247 kids later we concluded it was the most fun Halloween ever. Watching trick-or-treaters hit the piñata was a blast.

Things that amazed us #3: We expected kids to either aggressively pursue hitting the piñata or shy away, but most of the time they were shockingly analytical and courteous to each other. We witnessed a group of eight-year-olds employ “Eeny, meeny, miny, moe” to pseudo randomize the order in which they would get to hit the piñata. They then lined up in their self established order. Bizarre.

We’ve had some time to reflect on Halloween themes and coincidentally Ruth has been investigating smoke ring machines a la Disney’s Winnie the Pooh attraction. Maybe we’ll have a Heffalumps and Woozles theme next year. Or not. Having a theme isn’t important…