MechaPounce: Pulley-Driven Fun for Furry Ones

While I'm off chasing deadlines, this little invention keeps my kitten chasing dreams.

For them, it's none less than a wonderland of whiskers, wiggles, and wide-eyed play.

Conventional toys often lose their appeal quickly, so I wanted to design and build something that mimics the chase instinct by moving a toy along a controlled path using a motor and pulley system.

Unlike static toys or simple automated ones, this system allows the toy to travel between multiple points such as Point A, Point B and Point B keeping the cat engaged and curious. It’s fully mechanical and customizable, which means the movement can be adapted to different speeds, directions, or patterns.

The faster they zoom, the more calories go boom. ...and once the cats are tired, it’s nap o’clock.

Functions: -

1. Move a toy/ribbon along a pulley-guided path using a remote.
2. Control the speed and direction of the toy’s movement remotely easily.
3. Adjust or reposition the toy and pulleys for different layout.

Hardware Development Board:

1. Arduino (any Arduino will do)

Components Used:

1. 25mm Geared Motor High Torque (you will need to get a 25mm diameter and 4mm shaft diameter high torque motor with a rpm of 500rmp to 1200rpm).
2. L298n motor driver
3. A 12v battery or adapter.
4. Infrared (IR) Wireless Remote-Control Module
5. Jumper wires (you will need a mix of female to female and male to female wires.)
6. Bearings:2 x 608 Bearing size.
7. 3 x rubber band (It is important as it helps the yarn stick to the wheel.)
8. Crochet yarn or a strong thread. (I took a navy-blue colored yarn)
9. Ribbon or small toy. (Well, I tied a white feather to the pulley.)

Software:

1. Fusion 360 for Design
2. Arduino IDE to write and upload the code to the microcontroller.

Let me tell you this:

1. You can use any material.
2. Set the layer height to 0.2 mm.
3. Use as little as 5% infill for all parts, except the “base cover” and “pulley” parts—since they need to be strong, 15% infill is sufficient.
4. Enable supports only for the “motor base” and “base cover” parts.

Arduino Code: IR Remote Controlled Motor

You’re free to tweak parameters like motor speed. By default, the motor starts at speed 0 and increments by 10 up to a maximum of 255.

Before running the code, make sure to install the “IRremote” library using the Arduino IDE’s Library Manager. Once installed, upload the code to your board.

If your remote matches mine, the controls are mapped as follows:

1. Button 1 → Start the motor
2. Button 2 → Stop the motor
3. Button 3 → Toggle direction
4. Up Button → Increase speed
5. Down Button → Decrease speed

I you're using a different remote then just open the Serial Monitor and press each button to observe its unique signal code.

Replace the existing values in the code with yours accordingly.

Connect the Arduino and other components as shown in the wiring diagram.

1. Power Source Setup: Connect the positive terminal of a 12V battery (or a compatible 12V power supply) to the 12V input on the motor driver. Attach the battery’s negative terminal to the GND pin on the motor driver.
2. Powering the Arduino: Link the Arduino’s Vin pin to the battery’s positive terminal. Connect the GND pin on the Arduino to the battery’s negative terminal.
3. Motor Connection: Attach your motor wires to the OUT1 and OUT2 terminals on the motor driver module.
4. IR Sensor Wiring
5. Connect the sensor’s GND to the Arduino’s GND.
6. Connect the sensor’s VCC (positive) to the Arduino’s 5V pin.
7. Connect the sensor’s signal (S) pin to digital pin 2 on the Arduino.
8. Arduino to Motor Driver Control: Connect the motor drivers:
9. First control pin to Arduino pin 5
10. Second control pin to Arduino pin 6
11. Third control pin to Arduino pin 7

Follow the procedure: -

1. Print all parts once, except for the “base,” “base cover,” “protective cover,” and “pulley” Print these twice.
2. Install all electronic components inside the “motor base” and seal it with the “motor base cover.”
3. Ensure the IR sensor is positioned on top so it can receive signals from the remote.
4. The “base” is intentionally hollow. You may even fill it with any heavy materials you have on hand, like bolts, screws, or Gibson filled with water, to provide stability when the cat interacts with the device.
5. Once the base is filled, secure the “base cover” using super glue, then place a bearing on top, followed by the “pulley” part. You may apply glue here as well for additional stability.
6. Install the “protective cover” over the pulley, ensuring it doesn’t interfere with the yarn’s movement. Fix it in place with super glue. Note: This part may not appear in images as it was a recent addition.
7. Mount the motor on the motor base, route the wires through the provided gap, and attach the “motor pulley” on top. A separate “motor protective cover” fits over the “motor base cover” to hold everything in place. Again, use glue to keep it secure.
8. Finally, wrap rubber bands around all three wheels to improve grip with the yarn. Wind the yarn through the pulleys and attach a toy or ribbon at the end for playful interaction.

One practical and impactful modification for improving pulley-based mechanisms is deepening the grooves on the wheel rims for: -

1. Improved String Retention: Deeper grooves significantly reduce the chances of the string slipping or derailing during setup or high-speed operation.
2. Greater Compatibility: With deeper channels, you can also use slightly thicker strings or ropes without compromising performance offering more flexibility in material choice.
3. Enhanced Safety: A more securely seated string means there's less risk of sudden disengagement, which could otherwise cause tangling, jerks, or even minor injuries in fast-moving setups.
4. Durability Boost: Because the string experiences less lateral movement, there's reduced friction against the pulley rim edges. Over time, this helps prolong both the string’s lifespan and the pulley’s surface integrity.
5. Custom Groove Profiles: In the future, 3D printing or CNC machining could allow tailoring groove profiles not just in depth but also curvature for specific use cases like multi-string arrangements or bidirectional tension systems.

MechaPounce isn’t an official product or brand (yet!), but it does echo some fun references. The closest match is “Kitty Pounce,” an ability used by the Mecha Cat in Plants vs. Zombies: Garden Warfare 2. In that game, the Mecha Cat charges forward, dealing heavy damage and knocking enemies back, kind of like a feline missile with attitude.

So, when I coined MechaPounce as a title, I imagined it as a playful fusion of tech and instinct: a mechanical marvel that mimics a cat’s natural pounce. It’s got that energetic, and a sci-fi flair perfect for a pulley-driven toy that lets pets chase with robotic precision and feline finesse.