Mega City Block Upgrade - The Okey Dokey Chef

Once you start pimping out your Mega City One Block Storage Case it's hard to know when to stop...

The Okey Dokey Chef Animated Sign

I wanted my sign to be an advertising hoarding and one of the most famous signs in Mega City One is the Okey Dokey Chef as featured in the Supersurf 7 race story Midnight Surfer (progs 424-429).  I was also inspired by the famous Vegas Vic neon sign whose arm waving welcomed gamblers from all around the globe since 1951.

He wold make an excellent starting point to learn about how to control low voltage RC servos with Arduino.

The Chef

I found a nice piece of clipart online which had the vibe I was going for and imported this into GIMP for editing.  

I cut out the "Chef's Kiss" hand using the lasso tool and moved this over into  a seperate file.  This is going to be the sweeping hand which we will animate later using a servo.

I added a speech bubble with some appropriate text coming out of the side of the chef's head. 

Preparing for Tinkercad

I have learned that Tinkercad is a pretty simplistic modelling tool and it does not particular like creating complex curved or polygonal shapes.  The easiest way to solve this conundrum is to simply create a solid black mask version of your line drawn artwork.  This can be used as a background and because both shapes are exactly the same image size, they will register perfectly together when you import them into Tinkercad.

When I was happy with both files, I and exported them (and their solid black mask counterparts) as a PNG then converted into an SVG using convertio.com.  Each line drawn SVG is imported into Tinkercad for extrusion into a 3D object using the same technique I used to create my badges and Index Card RPG Card Back Stamps. I use an extrusion height of 30mm.

The black mask variant is then imported and the combined shapes exported as a single STL.  This gives me an STL file for the chef and a file for the arm which can be printed on the Anycubic Photon M5.

The Electronics

The core of this project is an Arduino nano.  These little boards are stupidly cheap and really easy to start your coding adventure.  Seriously, if an idiot like me can do it then anyone can.

The bit doing all of the moving is a 9g 5v 180 degree hobby servo which I bought in a twinpack from Ali Express for £1.79.

This was superglued across the gap between the Speech bubble and the chef's arm.

The Wiring and Code

I used the excellent How to Control Servo Motors tutorial on the makerguides website.  The servo has 3 wires Red (5v Power) goes to the 5v pin,  Brown (Ground) goes to the GND pin and the Yellow (Signal) goes to Pin 9.

The code example given is perfect for my purposes, but I did need to customise the start and end positions for the hand as it does not need to run the full 180 that the servo is capable of.  I also added a 500 millisecond delay at the end of each travel.

#include 

Servo myServo;  // Create a Servo object

void setup() {
  myServo.attach(9);  // Attach the servo to pin D9
}

void loop() {
  // Move from 30 to 135 degrees
  for (int pos = 30; pos <= 135; pos += 1) {
    myServo.write(pos);  // Tell servo to go to position in variable 'pos'
    delay(45);           // Wait 15 milliseconds for the servo to reach the position
  }
  delay (500);
  // Move from 135 to 30 degrees
  for (int pos = 135; pos >= 30; pos -= 1) {
    myServo.write(pos);  // Tell servo to go to position in variable 'pos'
    delay(45);           // Wait 15 milliseconds for the servo to reach the position
  }
   delay (500);
}

Troubleshooting

In my naievete I thought that the Arduino nano would be able to power this whole project.  However, the little servo apparently draws too much power to run continuously causing the nano to reset itself and creates some erattic animation.

I tried to mitigate this by adding increasing the dealy to 45 thereby slowing down the move, but sadly this was not enough.  It would have been nice to know all this from the start as an alternative board such as an ESP32.  

Anyway that is another story.  In the meantime check out the final result

Download the Files

I have also uploaded the Okey Dokey Sign STL files to Thingiverse if you should want to make your own version of this iconic comic book sign.

Let me know if you found this useful or if you have made your own animated signs for your own games