Why roam around with a boring pumpkin bucket when you can lay eggs in warm human intestines collect delicious candy with a robotic Xenomorph head?

This robotic candy bucket shoots out a small receptacle to retrieve candy and bring it back into the bucket.

Some 3D printing is required to create the linear actuator. Two servo motors controlled by a Circuit Playground Express, coded with MakeCode, power this project. 

Parts

Materials

For this project you will need:

• Scissors and/or box cutter
• Hot glue & hot glue gun
• Double-sided foam tape
• Pen/pencil
• Small screwdriver

Read on to learn how to create your own!

Connect your large continuous servo motor to the Circuit Playground Express by connecting the servo's red (or orange) wire to Vout, the yellow wire to A1, and the brown (or black) wire to GND. 

Connect the sub-micro servo to Vout and GND pads on Circuit Playground Express and the data (yellow) line to A2.

The 3D files for the linear actuator used in this project can be downloaded by clicking the button below.

This design for this project is based off of the Large Linear Servo Actuator published by potentprintables.

Bracket

Slimmed down and with some mounting holes added to the base.

Extender arm

Revised to extend to 215mm.

Once smoothed and assembled, your linear servo actuator assembly should look like this.

Getting Familiar with MakeCode

This project runs a simple Microsoft MakeCode sketch to control the helmet, and is easy to play with if you want to make changes.

Microsoft MakeCode for Adafruit is a web-based code editor that provides a block editor, similar to Scratch or Code.org, and also a JavaScript editor for more advanced users.

If you've never used the Circuit Playground Express with MakeCode before, this guide is a good place to start.

The Code

The code is shown below. For browser viewing, you may need to enable content. For example, in Chrome, click "Show Embedded Content" as the material is fed not from Adafruit but from Microsoft's MakeCode site.

To download the code, click the download link at the bottom of the window. To edit the code in MakeCode, click the box with arrow icon in the upper right corner of the window.

How to Upload Code

To upload code to Circuit Playground Express, follow these instructions:

1) Connect your Circuit Playground Express to your computer using a micro USB cable and press the small reset button in the center of the board. All the LEDs will flash red briefly, then turn green. Your computer should now show a removable drive called CPLAYBOOT. 

2) Click the Download button in the code window below to download the .UF2 file to your computer.

3) Now drag and drop the .UF2 file onto the CPLAYBOOT drive in your computer's file explorer or finder.

Once the file is dragged onto CPLAYBOOT the drive will automatically eject itself (your computer may give you a "failed to eject drive correctly" error, you can ignore this). The code is now on your Circuit Playground Express and ready to run!

Note: If you get a drive named CIRCUITPY, no worries! Press the reset button twice to get a flash drive named CPLAYBOOT. The project will not run if copied onto the CIRCUITPY drive as it is for CircuitPython.

Adjust Your Motor

Adjusting a continuous rotation servo so that it stays completely still when inactive can be accomplished by adjusting the potentiometer hidden inside the motor.

Take a small screwdriver and SLOWLY turn the potentiometer screw clockwise, then counter-clockwise, observing how this affects the direction of the motor until you find the spot where it stands still

Troubleshooting

Problem: My motor doesn't move!

Solution: Make sure that your Circuit Playground Express is connected to a power source (anywhere between 3V-5V is safe). If you're using a AAAx3 battery pack, check that the switch on the battery pack is set to "ON". If you are using the LiPo battery, be sure it is fully charged using the charger in the Featured Products.

Problem: My Circuit Playground Express doesn't show up as CPLAYBOOT

Solutions:

1. Be sure you have a Circuit Playground Express.  The Circuit Playground Classic will not work with MakeCode.
2. If you get a drive named CIRCUITPY instead, press the reset button twice in succession to get to CPLAYBOOT.
3. Some USB cables are "charge-only" and won't pass data. Try using a different USB cable and try using a different USB port on your computer.  
4. With the Circuit Playground Express plugged into your computer with a micro USB cable, click the small reset button in the center of the board. The lights should all turn green. If they don't, try double-clicking the reset button.

If things still aren't working, head over to the Intro to Circuit Playground Express guide for more suggestions.

More MakeCode!

If you enjoy MakeCode and want to continue exploring you can check out lots more MakeCode projects on the Adafruit Learn System.

Want to Get Back to CircuitPython?

If you ever need to convert your Circuit Playground Express back to CircuitPython mode, you can do so by downloading the appropriate .UF2 file from CircuitPython.org and dragging it over onto your CPLAYBOOT drive. See this guide page for the step-by-step instructions.

If you don't have an X-acto knife, the 3D printed handle used here can be found on Thingiverse and pairs well with standard utility knife blades to make an excellent hobby knife.

Alien Drool

As a final touch, you can use hot glue around the mouth to add some attractive-looking Xenomorph spittle.