# Servo Animatronic Tail ## Tools and Materials Here's a project for costumes, cosplay, cats, dogs, and lovers of tailed creatures. https://vine.co/v/OAYerz9D2YQ  The bulk of the project is 3D printed... only a few additional items are needed. - [Silicone tubing](http://www.amazon.com/gp/product/B00FXAA0BQ/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1) ~12 mm (outer diameter) - [Beadalon](http://amzn.com/B00279NNQA) stringing wire .61mm - Standard Metal Gear Servo - 30mm screws (almost any kind wil do - you only need two) - 10mm screws - 8mm screws - Spring from a ballpoint pen And, some basic tools. - Hot glue gun - Silicone adhesive - M4 tap (optional) - Wire cutters - Screwdriver Silicone tubing has an outer diameter of ~12mm and an inner diameter of ~9mm. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/054/medium800/3d_printing_IMG_3338.jpg?1415514813) Thicker stringing wire is better - your tail will last longer and will be more durable. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/055/medium800/3d_printing_IMG_3533.jpg?1415514835) # Servo Animatronic Tail ## 3D Printing Fire-up your 3D printer... and lets print the parts to make an animatronic tail - operated with a single servo.   ![](https://cdn-learn.adafruit.com/assets/assets/000/021/087/medium800/3d_printing_animatronic_tail.png?1415587245) Tweak / edit the design on Tinkercad... or get printer-ready files on Thingiverse. - [Tinkercad: Animatronic Tail](https://tinkercad.com/things/4oQD3fFYZic) - [Thingiverse: Animatronic Tail](http://www.thingiverse.com/thing:537467) All the parts except for the servo body and tail base can be printed without support material.  # Servo Animatronic Tail ## Servo Assembly You'll be printing several of the pieces in halves - mostly to optimize the parts for FDM printing. Sand the facing edges on a flat surface... ![](https://cdn-learn.adafruit.com/assets/assets/000/021/056/medium800/3d_printing_IMG_3486.jpg?1415515450) Don't blow the plastic particles away. When added to Super Glue, it creates an amazingly strong bond and helps fill gaps. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/057/medium800/3d_printing_IMG_3490.jpg?1415515483) You'll do this for the main servo wheel... ![](https://cdn-learn.adafruit.com/assets/assets/000/021/058/medium800/3d_printing_IMG_3488.jpg?1415515504) ...and both pulleys. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/059/medium800/3d_printing_IMG_3491.jpg?1415515552) Clean-up excess glue with an Xacto knife after it dries. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/060/medium800/3d_printing_IMG_3494.jpg?1415515598) Attach the servo with 10mm screws. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/061/medium800/3d_printing_IMG_3498.jpg?1415515635) Hot-glue the servo horn onto the pully wheel... make sure it centered! ![](https://cdn-learn.adafruit.com/assets/assets/000/021/062/medium800/3d_printing_IMG_3499.jpg?1415515665) Attach the pully wheel to the servo. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/063/medium800/3d_printing_IMG_3502.jpg?1415515718) Rotate the servo carefully and check to make sure that the servo horn has appropriate clearance. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/064/medium800/3d_printing_IMG_3503.jpg?1415515806) Tap holes, or carefully warm the screw with a hand-torch before driving it into place. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/072/medium800/3d_printing_IMG_3518.jpg?1415516286) I used two cabinet screws (30mm) to join the outer plate. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/085/medium800/3d_printing_IMG_3513.jpg?1415516942) Use 8mm screws and printed washers for each pully. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/073/medium800/3d_printing_IMG_3520.jpg?1415516337) Make sure that the servo wheel and pullys are aligned... to keep the tail a waggin' ![](https://cdn-learn.adafruit.com/assets/assets/000/021/074/medium800/3d_printing_IMG_3526.jpg?1415516368) # Servo Animatronic Tail ## Tail Assembly My first attempt at making a tail used all 3D printed parts... which caused too much friction and failed after only a half-hour. While digging through a box of project supplies, I found a length of silicone tubing that I used to make a peristatic pump a while back. Perfect! ![](https://cdn-learn.adafruit.com/assets/assets/000/021/065/medium800/3d_printing_IMG_3523.jpg?1415515942) You'll need to print-up a whole bunch of tail rings... take the length of your tubing and divide it by ~3cm to get an approximate count. The diameter of the hole in the middle of the ring is slightly smaller than the tube, which holds them in-place. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/066/medium800/3d_printing_IMG_3524.jpg?1415515989) You might want to add silicone adhesive to this end... as the tail wags, it can work its way out of the socket.  ![](https://cdn-learn.adafruit.com/assets/assets/000/021/068/medium800/3d_printing_IMG_3525.jpg?1415516056) Attach the tail base to the servo body with 8mm screws. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/069/medium800/3d_printing_IMG_3532.jpg?1415516097) Don't let the size fool you, Beadalon is incredibly strong... 40 - 50 lbs test! ![](https://cdn-learn.adafruit.com/assets/assets/000/021/075/medium800/3d_printing_IMG_3535.jpg?1415516429) Cut a length of bead-wire that is twice as long as the tail - adding an extra foot for safety and attachment to the servo wheel. Divide the length in half and loop at the top, and add a bit of hot-glue or silicone adhesive to hold the cap and wire in-place. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/070/medium800/3d_printing_IMG_3537.jpg?1415516146) Then, thread the wire down the tail. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/071/medium800/3d_printing_IMG_3540.jpg?1415516186) # Servo Animatronic Tail ## Adjustments We need to make reference marks on the wheel to guarantee maximal wag. 1. Carefully rotate the wheel to the far right and make a mark perpendicular to the servo body. 2. Carefully rotate the wheel to the far left and make a mark perpendicular to the servo body. 3. Then, divide the distance between the two marks in half... make your final mark. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/088/medium800/3d_printing_IMG_3505.jpg?1415589048) This, will be your guide when lacing the wheel. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/089/medium800/3d_printing_IMG_3506.jpg?1415589083) At the mid-point, drill a hole into the wheel. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/077/medium800/3d_printing_IMG_3508.jpg?1415516560) Flatten the area to that the screw sits flush against the wheel. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/078/medium800/3d_printing_IMG_3509.jpg?1415516622) Either tap the hole or pre-thread with a warm screw. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/080/medium800/3d_printing_IMG_3511.jpg?1415516714) Lace the beading-wire through each pully, around the servo wheel, and secure at the mid-point of the servo wheel. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/079/medium800/3d_printing_IMG_3542.jpg?1415516688) Rotate the wheel carefully to make sure that the wag looks right... asjust as necessary. When you're satisfied, add a little hot-glue to make sure that the beading-wire won't budge. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/081/medium800/3d_printing_IMG_3543.jpg?1415516773) Trim excess beading-wire... ![](https://cdn-learn.adafruit.com/assets/assets/000/021/082/medium800/3d_printing_IMG_3545.jpg?1415516810) Grab a spring off an old and dead ballpoint pen... we're going to use it for automatic slack adjustment. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/083/medium800/3d_printing_IMG_3546.jpg?1415516844) This will help prevent the beading-wire from falling off a pully. ![](https://cdn-learn.adafruit.com/assets/assets/000/021/084/medium800/3d_printing_IMG_3547.jpg?1415516875) # Servo Animatronic Tail ## Wag Baby Wag! Getting the tail to wag is super simple... and can be done with the example sketches that ship with the Arduino IDE. File \> Examples \> Servo \> Sweep ```auto // Sweep // by BARRAGAN // This example code is in the public domain. #include Servo myservo; // create servo object to control a servo // a maximum of eight servo objects can be created int pos = 0; // variable to store the servo position void setup() { myservo.attach(9); // attaches the servo on pin 9 to the servo object } void loop() { for(pos = 0; pos < 180; pos += 1) // goes from 0 degrees to 180 degrees { // in steps of 1 degree myservo.write(pos); // tell servo to go to position in variable 'pos' delay(15); // waits 15ms for the servo to reach the position } for(pos = 180; pos>=1; pos-=1) // goes from 180 degrees to 0 degrees { myservo.write(pos); // tell servo to go to position in variable 'pos' delay(15); // waits 15ms for the servo to reach the position } } ``` This works for Arduino UNO... or you can go less expensive with Trinket (requires adjusting the code for SoftServo library) or Pro Trinket (which is plug&play) See! https://vine.co/v/OAYerz9D2YQ Here's what the automatic slack adjustment looks like. https://vine.co/v/OAYidQxHnz1 The real question now is... what are you going to use your animatronic tail for / in?   ![](https://cdn-learn.adafruit.com/assets/assets/000/021/090/medium800/3d_printing_IMG_3759.jpg?1415599108) ## Related Guides - [Make it Move with Crickit](https://learn.adafruit.com/make-it-move-with-crickit.md) - [DIY Projector for the Nintendo Switch](https://learn.adafruit.com/diy-projector-for-the-nintendo-switch.md) - [Thermal Camera with Display](https://learn.adafruit.com/thermal-camera-with-display.md) - [Wireless BLE MIDI Robot Xylophone](https://learn.adafruit.com/wireless-ble-midi-robot-xylophone.md) - [Motorized Camera Slider MK3 ](https://learn.adafruit.com/motorized-camera-slider-mk3.md) - [Overhead Camera Rig](https://learn.adafruit.com/overhead-camera-rig.md) - [iPad Pro Bumper](https://learn.adafruit.com/ipad-pro-bumper.md) - [Boomy Pi Airplay Boombox](https://learn.adafruit.com/boomy-pi-airplay.md) - [Make It Glow: How to Solder NeoPixels, A Beginner's Guide](https://learn.adafruit.com/make-it-glow-how-to-solder-neopixels-a-beginners-guide.md) - [Ladyada's Toolkit](https://learn.adafruit.com/ladyadas-toolkit.md) - [Fisher-Price USB Controller](https://learn.adafruit.com/fisher-price-usb-controller.md) - [Guardian Robot – Zelda BOTW](https://learn.adafruit.com/guardian-robot-zelda-botw.md) - [How to Build a Testing Jig](https://learn.adafruit.com/how-to-build-a-testing-fixture.md) - [MIDI Solenoid Drum Kit](https://learn.adafruit.com/midi-solenoid-drum-kit.md) - [LED Sculpture Lamp](https://learn.adafruit.com/led-sculpture-lamp.md)