Fabrication

The dragon was mainly made out of laser-cut 6mm plywood, laser cut 6mm and 3mm acrylic, and 3D printed PETG pieces. A total list of materials and their use is shown in the tables below, split between structural/ functional and cosmetic

Assembly

The assembly of the Dragon automaton included building the bases, mounting schemes, links, and cosmetic items.

The main base was made out of laser-cut 6mm plywood, which included a main rectangular box that had only a bottom and two sides (on the short side). The bottom and two short sides were glued and then screwed together. From here, another two wide pieces of 6mm plywood were cut and then screwed together to form a removable top of the main base. The removable top had a hole cut out at the center to allow for the CAM - follower mechanism to interact with the secondary base.

The secondary base mounted the slider follower mechanism and was screwed into the removable top. The secondary base was attached via links to the wing mechanisms on the sides of the removable top. The wing mechanisms were held up using 6mm acrylic stands. These stands used slotted holes to press fit into the removable top. As well, the stands supported a fourbar wing mechanism that was made out of acrylic, shown below.

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Figure 1: Acrylic Wing Mechanism (Left and Right Wing)

The wing four-bar linkages were assembled using clear acrylic slotted links pinned together at their ends with shaft collars acting as the revolute joints, with the black link representing the input crank. The two linkage assemblies, laid flat on the table, show the two four-bar configurations that were used as the final wing design.

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Figure 2: Head with Jaw Mechanism (Open, Close)

The head mechanism was assembled using laser-cut acrylic links connected at pivot points with bolts, washers, and nuts acting as pin joints. The two photos show the beak in both the open and closed positions, demonstrating the four-bar double-rocker motion where the top jaw rotates upward to simulate an opening/biting action.

In summary, assembling the final automaton was a hands-on and highly collaborative process that unified fabrication methods such as laser cutting, 3D printing, manual assembly, and wiring. The plywood chassis was laser cut and finger-jointed to form the base enclosure that houses the motor and battery system, while the acrylic linkages, shaft collars, and ball bearings were assembled with precision. One of the biggest lessons we learned through this process was how critical communication and coordination were. Three separate mechanisms all needed to work together from a single motor input, with each division’s strict alignment on dimensions, timing, and attachment points. We also learned that no design survives the first assembled prototypes with completely successful mechanical components intact, and this was demonstrated when links needed to be adjusted, mounting points shifted, and parts reprinted.

Electronics and Circuitry

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Figure 3: Electrical Setup Configuration (Motor, Battery, Battery Holder, Wiring, Joystick, etc.)

We designed our electrical system to be driven by the consistent power of the single motor that drives the dragon’s multi-varied motion simultaneously. It is fundamentally a single-input, multi-output system, where the one motor depicted drives the wing flapping and jaw biting all at once through a coordinated mechanical drivetrain. We chose to keep the electrical system of this project as organized and separated visually from the direct automaton motion.

Power System

• The entire electrical system was cased inside the laser-cut plywood chassis beneath the main platform. This would allow all of the wiring to stay organized and out of sight (still visible) to preserve the visual presentation of the automaton during demonstration.

• A 9V battery and dedicated battery holder serve as our primary power source to ensure consistent voltage delivery to the motor throughout operation

• We secured all wiring connections using crimp terminals and ring connectors from our 320-piece terminal kit, and followed standard red and black polarity conventions throughout to keep the circuit easy to read and service.

Motor & Drive

• We chose a Bringsmart Micro DC 12V motor as our individual mechanical input and mounted it centrally within the undercarriage compartment. This motor drives the cam shaft that simultaneously actuates all mechanisms (the wing cam-follower four-bar and the beak double-rocker) through a single coordinated drivetrain

• 18-gauge wire was utilized for power delivery for flexibility and the ability to handle the current demands of the DC motor under continuous operation.

Control & Switching

• A DaierTek rocker switch was mounted on the exterior of the chassis so the operator can cleanly start and stop the automaton without ever needing to touch the wiring or disconnect the battery.

• A DIANN USB Type-C breakout board was one option as a secondary power input, which could be powered by plugging into a power bank source rather than relying solely on the battery.

Future Investigations

• Introduce a PWM motor driver circuit to regulate motor speed and torque, allowing the dragon's motion to be tuned without mechanically modifying the drivetrain

• Include a current sensing circuitry to monitor motor load and automatically cut power if a mechanical jam occurs, protecting both the motor and the mechanical linkages

• Implement a rechargeable lithium-ion battery pack with a dedicated battery management system for safer, longer-lasting, and more consistent power throughout operation.

Software Development

On the software side, we kept our automaton as a fully self-contained device with no laptop or external interface, just a single rocker switch. This introduces a straightforward device that operates with simplicity in a live demonstration setting. The DC motor was controlled entirely through the physical rocker switch, meaning no microcontroller or programmatic speed control was needed for normal operation. However, when looking ahead, we would like to introduce more software-based features that add to the artistic character without significantly increasing system complexity.

Future Investigations

• A microcontroller, such as an Arduino, could be introduced to allow programmable speed control of the DC motor to adjust the automaton’s motion without physically modifying the mechanical drivetrain.

• Program addressable RGB LEDs to synchronize lighting effects with the dragon's motion cycles, such as linkering lights during wing flapping or glowing eyes that animate with the jaw movement.

• Incorporate sensors such as proximity or sound sensors to make the automaton reactive, such as wing flapping or LED changes when someone approaches, creating an interactive experience.