More Pumpkin Photography - Rotting and Polaroids

The jack o'lanterns are waning almost as fast as my stock of 4x5 Polaroid Type 54 film.  As promised in a recent post, I've take a few Pumpkin Polaroid shots.  I'm heartbroken that this film stock is no longer made.   Unopened boxes of 20 sheets are going for hundreds of dollars on ebay now.   I've run out, but just bought 12 more sheets on ebay for $37.00, which will likely be my last.   On top of that, my Polaroid back that I use in my Crown Graphic is really acting up.   It doesn't want to spread the processing chemical goo evenly across the picture.   I lost three of five shots today, two to this problem, and one to a jam that occasionally happens.     As is often the case when trying to take shots close up, the focus leaves something to be desired.   It is a total crap-shoot to get the focus correct the first time under about 8 feet.   But since I was low on film and losing shots to technical problems, no retakes came out.

I also took more shots with my Nikon, back to one of my favorite subjects, the rotting jack o'lantern.    I tried to mimic the look of the Polaroids by taking them black and white and sepia.

Pumpkin Prowl 2009

Pumpkin Prowl at Woodland Park Zoo finished up last week. Finally getting caught up on sleep and just now getting pictures posted.

The weather was iffy on Friday and Sunday, but Saturday was nice and it was *packed*. Donovan's full spider made its debut, it really looked great. His banshee got worked over as well and kept people mesmerized. The witch got a voice this year and movement with an over-sized FCG mechanism. The new controller worked flawlessly, though there is a lot of programming to go before it gets its full web control.

Arduino, Vmusic2, XPort -- Halloween Controllers

I've been working on advanced concepts in controlling Halloween displays for a long time. But I've only just started executing some of my concepts last year. The tentacle controller was the first, but it is still very specific to the tentacle. I hope to have a set of fundamental capabilities in every controller and a set specific to the particular exhibit/device.

My microprocessor platform of choice is still the arduino, I'm excited to see the broad range of variations available, especially the Arduino Mega, I need a lot of I/O. The most important feature of my controller concept is that they are networked and can be remotely controlled, configured, tuned, and monitored. That means adding an ethernet interface. I've been experimenting with the Lantronix XPort AR. This device is amazing, so many protocols built-in, including SSH, HTTPS, and email. The built-in web server appears advanced and there are numerous configurable pins. As these devices go, it is on the pricier side (~$65) but you get a lot of features. BUT.... the downside is that you need a software development tool kit to really modify the device for your project. You can drop basic files on the device that the web server will see, but there is some secret sauce in here to have the web server talk to the UARTs and configurable pins. Too bad, it was a promising device but I'm not going to buy the tools. I don't even know how much they cost, you have to talk to salesmen...ick. Come on Lantronix. Give us the razor and we'll buy your blades like crazy. I still haven't decided if I should stick with this device, or just go with a really basic ethernet to serial device like this one. Half the price, but I would have to move some capabilities into the Arduino, like email alerts. In the XPort AR, I can just trigger a pin high which in turn sends an email alert. I have to make this decision soon! Need to get a couple ordered.

The other thing so many Halloween props need is quality sound. I've been searching around for the right method and finally decided on the Vinculum Vmusic2. This is a slick device, a full MP3 player with a serial interface. It has a USB port for a USB fob with MP3s and a 1/8" mini stereo jack for output. Then a set of pins for the serial and power connections. It was frustrating getting it to fire up the first time, the docs are worthless. There is an excellent instructable here on getting this thing set up, but even that didn't point out the key step. Then I found this reference from the Garage of Evil -- fellow high-tech haunters and my problem became clear. By default the Vmusic2 is setup for a CTS/DTR hardware handshake. You can tweak the settings through their firmware editor to just do tx/rx. But I couldn't get the device to come alive, which was required to pull the new firmware from the USB stick. I was beginning to think the default firmware wasn't on the device. Others have alluded to this in numerous posts, which then requires you to jump through hoops with the right cables to talk to the device to flash it. But the trick is to tie CTS to ground, that's it. The device woke up, reflashed itself, and everything is good. I dropped a couple MP3s on a thumbdrive and was soon talking to it through a serial connection firing off music while tweaking the controls. Nice! So in moments I'll be wiring up the first one to the current controller I'm working on. The picture here is the in-progress shot. A chassis from an old Sun outboard SCSI drive (12v and 5V) supply built-in, Arduino, protoshield, several relays, the Vmusic2, and much more to come.

Boomazium -- at Pumpkin Prowl

We transform the zoo's Zoomazium facility into Boomazium for Pumpkin Prowl. Here is another video showing more of Boomazium:

The Tentacle

First, I'm not quite sure how I ended up making a tentacle, I just got sucked into this project bit-by-bit until it consumed me. I had thought about making a big tentacle at one time, but it seemed a daunting project. Then I saw this off-the-shelf tentacle prop from FrightProps. I don't buy too many off-the-shelf props, but this was really well done, as is their octopus. The tentacle is about 5 1/2 feet long and is foam filled. The foam in the first one was pretty stiff. I've since bought a second, and the foam is now very flexible.

I still wasn't planning on making a tentacle prop but then I saw these two air-muscle instructables (one and two). I've never been a fan of pneumatics for props, too jerky, "digital", and *loud* hissing air. (Okay, one major exception has been the high-end prop boyz like ScareFactory. They have several amazing pneumatic props that have terrific motion and no extraneous noise.) But the air-muscles appealed to me as they had an organic look and feel and appeared inexpensive to produce. I found local parts and made a prototype, and I was hooked. The air-muscles deserve a post of their own, so I'll skip the detail for now.

The air-muscles would give life to the tentacle making it capable of some complex motions, I was hoping much like a cat tail. But the tentacle couldn't just sit there, it had to start hidden and emerge its entire length. It also needed a lift mechanism to enable up and down motion. I didn't think it would need left/right motion, that would come from the tentacle itself. I originally envisioned 8 muscles in the tentacle, 4 in the base, and 4 in the "finger" as I came to call it. Gravity proved a major difficulty so I ended up leaving out the down actuator in the base, for a final count of 7 air-muscles inside the tentacle. Then I would need two typical air cylinders, one for the forward/back motion, and one for up/down. I imagined the up/down to be straightforward, but the forward/back was going to be difficult as I needed 6 feet of linear travel. I worked through a variety of possible solutions but thought the classic scissor would work best given my budget.

Seven air-muscles and 2 air cylinders meant I needed 9 total air valves. Again I had no previous pneumatic experience but knew I didn't want 9 individual valves. I spent a lot of time researching the options. Solenoid valves (and all the myriad connections) get expensive quick. There are so many variations on valve types I'm still confused. I ended up buying a valve bank on Ebay that had 10 valves in one compact unit for about $150. While I waited for this to show, I went back to the mechanical and tentacle construction.

I originally planned on having a small 4-wheeled cart on 2 parallel tracks. But while wading through my favorite metal yard, I spotted a "T" shaped aluminum rail. I redesigned my idea on the spot and went for a monorail approach. The cart would get more complicated, but the overall design was simpler.

This picture shows the monorail with 2 aluminum supports at each end. The (first) aluminum scissor mechanism, and the first several components of the cart being test fitted. The cart is made of 1" square steel tubing and flat steel. This was also my first foray into welding. I borrowed a small wire-feed welder from Donovan, bought leather gloves, leather apron, and a $50 auto-darkening helmet from Harbor Freight Tools and off I went. I'm now a total welding junkie and a welder is high on my tool wishlist. My advice for any other welding newbies, I think the auto-darkening helmet makes all the difference. My welds aren't pretty, but they are very functional. Here is a closer look at the cart, before it had the lifting cylinder in place.

The cart was designed to convey the tentacle (via the scissor extender) and the (skateboard) wheels give it support in every direction.

And back to the pneumatics, I was really in the dark on proper sizing of the cylinders, tubing sizes, and pneumatic connector(hell). The scissor mechanism worked pretty well but required quite a bit of force to get it moving. I ended up buying (Ebay) a monster 3" cylinder with a 12" stroke for the scissor, and a 1" cylinder with a 6" stroke for the lift mechanism (FrightProps). FrightProps sells many pneumatic parts and they turned out to be my best off-the-shelf source for connectors, individual valves, and actuators. I researched procurement extensively but couldn't find a better selection and pricing (except for some items on Ebay, which were riskier.)

The mechanics were coming along now, and my (first) Ebay solenoid valve arrived. After much anticipation, I couldn't do anything with this device. It was in great condition, but the configuration of this particular device made it unusable. The connectors were all metric (couldn't source tubing in time) and small, but most important, the solenoids were a twin configuration. Meaning I would need twice the number of digital i/o ports on my controller to operate this thing. Even with all I've learned on air valves, I'm still not sure about the configuration on this particular unit. Time was becoming a factor now, I could order 9 individual valves from Frightprops, or I could try again on Ebay with another valve bank. I searched, researched, and ended up trying again on ebay. This time I bid on an 8 valve unit that looked older, but I was able to verify that it had 1/8" ports (for 1/4" tubing), single solenoids, set up for doubling acting cylinders, and it also had an air regulator on every valve! I won the auction and waited again. I did end up ordering one individual valve from Frightprops that I used for the up/down cylinder. This cylinder was only single acting, but with this 4 way valve I could throttle the exhaust to slow the descent (from gravity).

The full mechanism was coming together now, you can see the (skinned) tentacle, the big actuator connected to the scissor, and the scissor connected to the cart. The lift cylinder hadn't arrived yet. The scissor mechanism is steel now, as the big cylinder was so powerful it quickly destroyed my aluminum scissor. Even the steel scissor has been torqued, but I've got it tuned now and it is working well.

I haven't addressed the structure in the tentacle yet. I wish I had a picture to make the description easier. Again the tentacle was a standard foam filled prop. I carefully skinned the tentacle, trying not to stretch or tear the skin. There are seams that run the length of the tentacle, they were not completely sealed in the first tentacle. But I got it all off intact. I then sliced the underside of the foam structure and carefully carved out the interior leaving enough foam to support the skin. My original plan was to have a "skeleton", some sort of flexible, yet non compressible structure down the center. But then I thought the rigid foam would be enough to maintain this function, almost like an exoskeleton. I made a series of panels from a plexiglass-like material I get at Tap Plastics. It is softer than regular plexiglass, but is easy to work and shape. The panels were glued into the tentacle with E6000 adhesive (I really like that stuff!) and spaced at regular intervals. The base air-muscles attached at the base panel, then connected to cables that extended through several more panels. The cables attached about 2/3 the way up into the tentacle. The finger air-muscles anchored about half way up into the tentacle, then attached to cables that went to the very tip. The base cables overlapped the finger air-muscles to give some continuity between the two sets of muscles. The cables were run through channels in the outside edge of the tentacle, supported in the panels. So the effect of contracting a muscle, pulled the cable on the outside edge of the tentacle, which was then pulling against a point further up in the tentacle causing that side to constrict. It works pretty well, though I had hoped for more flex than I got. It I did this again, I would go back to a central spine design.

The valve bank arrived, and this one was going to work. The individual regulators turned out to be a really nice feature.

It is time to talk about how to control this beast. I'm using an Arduino controller (Diecimila) which handles the core logic for all the actuators, and also handles the trigger for the prop and a few other inputs and outputs. There is also a higher level user interface program that was supposed to run on an old touchscreen tablet that I have making for an easy-to-use test and control interface for the tentacle. That was written in Processing. This was my first project with the Arduino controller. I've used other controllers in the past but this one has so much supporting hardware and software it is easy to use. I used Processing for the GUI as it uses a very similar programming environment and language syntax with the Arduino. But likely next time, I'll just do a web interface that talks directly to the Arduino. I used the proto-shield for the arduino to add the driver circuits from the digital I/O to the solenoids. They needed about 6W each and I added in diodes to the connector on each solenoid to protect from inductive spikes. I'm using a I/R detector from Parallax to trigger the tentacle into action. This was mounted above the "Object of Great Desire", as we came to call it. It was a metal object d'art with a Blinkm LED unit inside glowing and changing colors. If you touched the object (just needed a hand near) , the tentacle came to life, presumably guarding the object.

There is much work to go in programming the tentacle. I've programmed several canned routines but want to capture more interesting motion. In watching the tentacle move, it has a few moments of complex motion that are really nice. I think I can get more of this if I have a better way interact with the tentacle, maybe through a joystick. I also plan to add several servo controlled or proportional valves to be able to vary the air flow. I'm doing really primitive pulse width modulation on the lift and forward/reverse actuators, but plan to program PWM capabilities for any actuator -- that may help to make the motion more analog.

Two videos, the first is a series of snippets of The Tentacle in action at Pumpkin Prowl. The second includes behind-the-scenes views of the tentacle mechanism in action.




And here is the behind the scenes version:



And more behind-the-scenes pictures here.

Pumpkin Prowl 2008

For three years running now I've been transforming the Zoomazium at Woodland Park Zoo here in Seattle into the Boomazium for the zoo's Pumpkin Prowl event. The zoo is such a great Halloween venue, and the Zoomazium is perfect for a haunt. We do a very young-kid friendly event, but that is not a problem as I have a haunt style that works for all ages. I'm not into gore/slasher/in-your-face scares, I prefer a subtler themed approach that is more interactive and integrated with the setting.

My haunting colleague Donovan Allen, who happens to work at the zoo doing exhibit technology, and I have developed a collection of props now that we use that integrate well with the control system Donovan developed for the interactive exhibits in the facility. His Z-Play system controls all the lighting, multi-zone audio, video/multimedia, kiosks, and triggers throughout the whole place. We interface several of the major props into the system to have high level control of the entire event. We debate constantly on control techniques, but that is fodder for a different post.

My newest prop was The Tentacle. This prop just about did me in. It was incredibly fun to develop, but it was a lot of work. And it took until the 3rd day of running until it was stable and functioned correctly all night without intervention.


We chose to put the tentacle in our explorer's tent, primarily as it was the easiest placement first time out-of-the-gate. The tentacle will also get its own posting soon. Video is on the way of it in action as well as a behind-the-scenes view.

The folks at the zoo are great to work with. It is a complicated place and budgets are tight, but everyone seems to rally when it comes down to the event. The staff carves *hundreds* of pumpkins that are displayed all over the zoo. One frustration though is that we can't use fog inside the Zoomazium at the moment. The smoke sensors are way too sensitive, as we discovered last year in the middle of the night during a fog test. We tried to get a firewatch procedure in place this year, but to no avail. Hopefully by next year as I need FOG! My scarecrow just isn't the same without it. We also did a private party this year, for a donor that won a "Halloween party in Boomazium" at the zoo's Jungle Party Auction event. That was great as it was nice to get a little more mileage out of all our hard work in setting this place up. The Pumpkin Prowl event is only 3 days and only 3 hours each of those days. I would love to see this expanded as Pumpkin Prowl has the potential to be "the" family friendly Halloween event in the entire NorthWest.

Here are some Pumpkin Prowl pictures and here are tentacle pictures. As I mentioned, video and another posting will be coming soon to talk more on the tentacle.

Pumpkin Prowl - Halloween 2008

The Tentacle

First blog post. Testing 1, 2, 3....

I've put off starting a blog for a really, really long time. I just didn't want something else hanging over my head. But I've seen many good examples for using a blog as a repository of information for a given subject over time. I just reserve the right to go dormant. So here goes....

I'll primarily be using this blog to discuss my favorite Halloween projects. I've been a fan of Halloween for a very long time now, and was an early contributor to the halloween-l usenet group. But a blog is a better vehicle I think so it is worth a try.

And finally, as to the name, Tangle of Wires. My sister once described my room as I was growing up as a "tangle of wires." Everything I do seems to come with its complement of wires, and yes, they are usually tangled. My career in I.T. has been nothing but a tangle of wires, and every Halloween project comes with a larger and larger tangle of wires. So, it seems appropriate to embrace and roll with it.