Halloween Cookie Monster and Gonger Food Truck!

With the advent of Halloween, my family's creative juices start flowing to figure out what my daughter will be and what accompanying build I can undertake. I've been a busy Halloween dad these past few years. I built the Trolley from Daniel Tiger's Neighborhood two years ago (the kiddo was Daniel Tiger), a Circus wagon last year (the kiddo was a circus ringleader), and if my daughter was going as Cookie Monster from Sesame Street, she needed to have his fancy-shmancy Cookie & Gonger Foodie Truck! The Cookie Monster food truck had to have a movable serving window, doors at the back to load the food in/out, room for driver Gonger (with a semi-functioning steering wheel), a counter for hungry (or maybe sometimes hangry) patrons to wait at, a Special-of-the-Day board, regulation Massachusetts license plates, lights, music, condiments, you name it -- we have it!

Supplies

If you choose to undertake this project, there is no set recipe. Build what works for you based on what you have. The fun of it is to try and utilize what you already have. This advice does not help the adventurer figure out what they need, admittedly, so the upshot is be creative.

Plywood (I used 3/4" for the base and 1/4" for the walls)
Simple common boards of various dimensions from the local home store
Arcade style buttons (I bought mine from Adafruit)
Circular foam pieces and wooden dowels (to make the steering wheel)
Lots of spray paint: orange, black, aluminum-colored, white
Pulleys (from Amazon)
Springs (from the local hardware store)
Lots of LEDs: ones to go around, headlights, puck lights (some I had, some I bought on Amazon)
Accoutrements from the Dollar Store: I got the metal grill, wooden backings for emblems, googly eyes, so many items that help bring it to life for the simple price of $1.25
Plexiglass: for the windows (got it for free)
LOTS of screws
A wagon (or equivalent) to tow everything in
Pool noodles
Raspberry Pi (3 or 4), lots of wires, and connectors
Transistors (I used 2N2222A), resistors (1 and 10 Ohm), and heat shrink tubing

Step 1: The Design

There are a few key rules:

Aim high and then shoot straight: I like to think about all the cool bells and whistles I want the build to have. The act of writing it down and then looking at a calendar helps me rack and stack the features I want and consequently be honest about what I actually have time for. It will also help you figure out what things you want to design/build vs go out and buy.
Plan with transportation in mind: If you want to parade your creation in some cool town Halloween parade or event that is not in walking distance of your humble abode, be mindful of space restrictions given your vehicle that the food truck will fit in. I had my father-in-law's truck to use, which has a cap, so I had to be mindful of height restrictions.
Consider your budget: Let's face it, post-pandemic prices are abysmal. Sheets of plywood cost so much more than they should. If you're going to buy a 4 ft. by 8 ft. sheet of plywood, take the time to plan the maximum number of pieces you can get out of it -- make a cut sheet! Your bank account will thank you. I definitely tried to do this and it helped me greatly. Beyond that, I tried to be creative and find other parts at the dollar store where things cost -- $1.25 (don't ask). If you have an awesome spouse with an artistic eye, they can come in handy with this step. Lastly, you could just go gangbusters, spend a ton of $$$, and hope you win $1,000 on some cool DIY maker website contest to offset your spending ;) But, as my boss reminds me, hope is not a strategy.

Step 2: Building the Infrastructure

You've got a design, on paper, with numbers. You are so golden. Follow your design until real-life kicks in to cause you to adapt and change when necessary. Once you start doing this, you are a professional.

In my builds, I am not allowed to drill into or mar the family wooden wagon. So I always fit 2 by 4's around the perimeter and then screw a large sheet of plywood to those to form the base. From there, I ended up putting support boards around the plywood which I can screw my posts into to create a rough frame for the food truck.

The parts visible in some of the pictures are the frames for the back doors, the serving window on the side of the truck, the hood, and generic shape of the food truck itself.

Step 3: The Serving Window

Oh I had grand plans for this. (See the bit about Aim High...). My daughter and I watch a LOT of Mark Rober on YouTube. He's a complete inspiration, and incidentally who I want to be when I grow up. Also, my daughter is excited to watch his videos -- so I'm hoping she catches the STEM bug. I thought to myself "I'm gonna Mark Rober this build and install a button, that when pushed, will cause a garage-like door in the window to raise and/or lower. That was the plan.

I started to cut the slats for the window-door and connected them with hinges so it would be able to bend and be somewhat pliable to follow a track (much like a real garage door). It was then I realized how heavy the door was and that I would need a properly sized motor to raise and lower it. After a lot of back and forth, and as much as I wanted to automate this part of the build, I had actually never worked with motors before or done the proper analysis of mechanical advantages to accurately estimate the SWaP (size, weight, and power) needed. Looking at the calendar, I acquiesced, decided to be more realistic, and make this a manual process. Spoiler alert: It totally worked out on the big day itself, and wasn't a big deal! Nonetheless, I decided to press forward and lower the weight just in case by removing the hinges and instead drilling holes through each board through which I ran a reasonably strong rope through it that was tied off at the end.

This window-door now had to ride along a track. After planning it out with a friend, he mocked up a measurement-accurate model out of extra wood lying around so we could test different curvatures to see what would ride along the track while still leaving room for the ceiling. Again, after a bit of back and forth, we settled on the correct design and he cut it out and installed it.

Lastly, I had to decide on the mechanism to raise and lower it. I had an old wooden closet rod lying around (after we renovated our closets) and cut that to the proper length. Cookie Monster would then pull down on it with his hands and that would raise the door over the track via some pulleys installed on the ceiling. On the last slat of the window-door, I installed some springs which stretched as the window-door moved upwards. The idea behind this was when Cookie wanted to close the window-door again, the stretched spring force would move all the slats downwards. To lock the window-door in the raised position, I quickly fashioned two wooden hooks that would grab the rod and prevent the window-door from closing again. Overall I was pretty happy with how this turned out!

Step 4: Plywood and Paint

This step is pretty self-explanatory. The one pro-tip here is to use plywood with enough heft to be durable but not thick enough so that it's either too expensive to purchase and/or too heavy to lift. I settled on 1/4" plywood which was easy enough to cut into pieces (according to my cut plan) and install. The second pro-tip is to definitely countersink your screws so they aren't sticking out and nicking your appendages or those of Cookie Monster's.

The paint was the fun part. The food truck from the show had this dull, dingy orange color. I, however, wanted this food truck to shine! I went to the local home store and found the most vibrant glossy orange I could. It just so happened that it was the same orange color I had left over from building my daughter a rainbow-colored wobbleboard last year, so I just picked up a few more cans and I was in business.

Step 5: Accoutrement City

Up to this point what I had built was the basic chassis. It was recognizable as a truck but it didn't have charisma and certainly wasn't the Monster Foodie Truck yet. To bring it to life requires those artistic touches that propel your build to the next level. The following list is what I did to achieve that goal:

Orange pool noodles (from the dollar store) that were cut and used as front/read bumpers
Corrugated metal pieces (from the dollar store) that became the grill in the front
Foam pieces (typically used for flowers and bought at -- you guessed it -- the dollar store) and wooden dowels that became the steering wheel
Old plexiglass pieces (donated by my in-laws' friends) which became the front windshield and driver/passenger side windows
The Monster Foodie logo (made from wooden craft pieces available at the dollar store) mounted at two locations on the truck
Aluminum-colored wooden trim pieces to outline a non-functional driver/passenger door
Metal handles (from the dollar store)
A kids playset of ketchup, mustard, salt, pepper, and hot sauce (more dollar store goodness)
A serving counter which fold down or be held up with metal chains (it was also wrapped in a faux marble paper to make it look all fancy)
A driver chair for Gonger fashioned out of extra wooden pieces that my wife made fun of me for since it looked like a high chair
Cookie monster face masks and laminated printouts of cartoon cookies which were pasted on the back

But my two favorite things were:

The license plates! My wife got the design of the Massachusetts license plates and made a ton of variations for us to sift through. We decided on Gonger for the front (since Gonger was the driver) and Cookie for the back. These images were printed out on normal printer paper and then I used some 1/8" plywood lying around (from the previous Halloween build) which was used as a backing, and then extra plexiglass to rest on top. I then made a wooden frame for everything which was painted the same aluminum color. I attached it via velcro -- it just came out awesome.
This one is pretty small but it's the hood ornament. It's simply a piece of wood screwed into the hood with a foam backing and Monster Foodie emblem glued to the foam. For some reason it just made the whole front of the truck pop

Step 6: Electronics

I have been lucky to reuse the same Python script year after year with minor tweaks. This year was no different. Usually the changes involve deciding which GPIO pins on the Raspberry Pi (RPi) will be used and what music will be playing.

I decided on having a button in the middle of the steering wheel to play ridiculous horn sounds, jalopy engine sounds, and even an annoying car alarm. Perfection.

There would also be two buttons on the driver's side which would control the headlights and playing the music. The headlights were especially fun because year after year I always noted that when I plug those directly into the RPi pins, the amount of light thrown out was minimal. I knew I could do better. Messing around in my workshop downstairs, I ended up plugging them into a 5 and 3.3V power breadboard to let it draw as much current as it wanted. It shined like the sun. So, I took the opportunity to wire up a transistor-based circuit (using this YouTube video as a guide) to have the RPi GPIO pin trigger the transistor to open up the collector-emitter current and really allow the LED to throw out a ton of light. I was extremely happy that I did this since it really lit up the street on the big night -- until the battery drained pretty quickly (since I miscalculated the total number of hours it should stay active for)

Because it was going to be dark during trick-or-treating, it's important for the food truck to be well-illuminated. I had a 66 ft. run of LED lights from the prior year's Circus Wagon build which I used to run around every nook and cranny of the truck to ensure it was visible to the neighborhood and the ISS. :)

A pic of my messy electronics cabinet (which was literally under the hood) can be seen. It's not the prettiest thing I've ever done, but it was also completed on 30 October, so I chose functionality over aesthetics.

Lastly I bought some puck lights from Amazon which I used to illuminate Gonger in the front, Cookie Monster behind the serving window, and 2 others to be the tail lights. This worked great and really made the innards visible.

Step 7: The Maiden Voyage

I finished at 9:45pm on Sunday, 30 October. Could I have cut it any closer? :) I began around mid-September and I honestly thought I would be done well before 30 October. This just proves to me how much nuance and course-correction existed. But in some sense that's the fun of doing this type of work; you get to react and adapt as you navigate your way to the end.

After coming home from work on Halloween, I was excited to go out with my daughter. Beforehand, my wife and I thought it would be cool to do a side-by-side with the Cookie Monster Foodie Truck and the Hooper's Store playset that we've had for a time. It was a little mini Sesame Street and it made us smile.

We took it out at the allocated time and it just worked. We got a lot of oohs-and-ahhs from folks in the neighborhood and it was a good ice breaker to talk to those neighbors you don't always see a ton. It was an incredibly successful Halloween and the smile on her face made the late nights absolutely worthwhile.

(P.S. I would show embedded video demonstrating some of the songs, but I'm having copyright warnings pop up in YouTube when I upload the videos, so since I don't want to get sued, I'll only do what I'm allowed to do :) )