Are you looking to bring your Servo Skelly project to life with realistic, unpredictable movements? Many builders want to avoid complex programming but still achieve dynamic motion in their animatronics. This guide will show you how to easily add random servo movement to your servo skelly using a simple circuit board. This method is perfect for beginners and allows you to control up to two servos, making it ideal for creating lifelike motion in your skeletal creations.
To get started, you’ll need a specific circuit board designed for random servo control. These boards typically come with adjustable settings to fine-tune the movement speed and frequency. For this project, we’ll focus on setting up a single servo for your servo skelly, ensuring smooth, sporadic motion that won’t strain the servo motor or the delicate skelly parts. Jerky, fast movements can cause unwanted power spikes and potentially shut down your power supply, so we aim for realism and reliability.
Alt text: Close-up of a servo circuit board showing three potentiometers being adjusted with a small screwdriver to control servo speed and movement range.
Before wiring, some preparation of the circuit board is necessary. Since we are only using one servo channel for this servo skelly application, we can trim down the board to save space and simplify wiring. Cut off three pins from one side of the output connectors as we will only utilize a single channel. Additionally, on the power input side of the board, you can also remove the third pin, as we only need the positive and negative connections. To prevent any electrical shorts, apply insulating tape between the servo’s metal casing and the back of the circuit board. It’s also helpful to slightly bend one pin forward and another backward on the power input for easier soldering.
Next, securely attach the circuit board to the servo. Hot melt glue is an excellent choice for this, providing a firm hold while being relatively easy to remove if needed. Plug the servo into the output side of the circuit board, ensuring the brown servo wire is connected to the negative terminal. Neatly bundle the servo wire and use hot melt glue to keep it in place and organized. Remember, all of this assembly needs to fit within the servo skelly’s housing, often a white tube, so take your time and ensure a compact arrangement.
Now, for the power wiring – and this is crucial: *** IMPORTANT NOTE ABOUT POLARITY! *** Depending on whether you are working with a “skelly” or an “inferno” model (if applicable), the power plug polarity might be reversed. Double-check your model to ensure you connect the positive and negative wires correctly. Incorrect polarity can prevent the circuit from working or even damage your components.
Carefully route the power plug wire through the designated holes in the servo housing and the torso ring of your servo skelly. Thread the plug wire up through the bushing flange and its hole. Cut two small pieces of heat shrink tubing and slide them onto your power wires. Solder the red wire to the red wire and the black wire to the black wire of your power supply, matching polarities. Slide the heat shrink tubing over the soldered joints and apply heat to shrink and insulate them.
Push the power wire back up, creating some slack below. Strip small sections of insulation from the red and black power wires. Solder the red wire to the positive pin and the black wire to the negative pin on the circuit board’s power input. Apply a small amount of hot melt glue to these solder points for extra insulation and strain relief, preventing accidental contact and securing the wires. Pull any excess wire back down so that the soldered joints and heat shrink tubing are positioned below the top of the bushing ring. This prevents any interference with the rotation of the servo skelly’s grey tube or housing.
Finally, it’s testing time! Plug the power wire coming from your circuit into the neck plug of your servo skelly or inferno model, which originates from the torso. Turn on the power using the skelly’s regular power switch. After a few moments, the servo should begin to move randomly from side to side. Observe the wire travel within the slot to ensure that when you mount the torso ring, the wire will not be pinched or crimped as the servo moves back and forth.
One last point regarding power: The stock power supply included with many servo skelly or similar animatronics is often a 5.9V 1.5 amp adapter. This is adequate but can be borderline, especially when starting up. You might experience occasional shutdowns requiring you to press the power button a few times to restart. If you want a more robust and reliable power source, consider upgrading to a 2-3 amp power supply. Waterproof models are readily available on platforms like Amazon for a reasonable price and can provide more stable power for your servo skelly project. With this simple circuit, your servo skelly will have captivating, random movements, enhancing its spooky realism without the need for complex programming.
