Hacking Alexa: Building an Animatronic Virtual Assistant with Personality
0:00:09 Introduction & Motivation: The creator expresses disappointment with the lack of personality in modern virtual assistants like Alexa, contrasting them with expressive computer characters envisioned in older sci-fi. The goal is to give a virtual assistant a more "alive" physical form.
0:01:14 Project Overview: The plan involves hacking an Amazon Echo (Alexa), adding animatronics for expression, and using an old CRT television screen to visualize the voice.
0:02:40 CRT Screen for Voice: An old black-and-white CRT television is disassembled. The core idea is to use its screen to display the assistant's voice visually, creating the illusion of a mouth and enhancing the feeling of interaction.
0:03:35 CRT Hacking Method: The horizontal deflection signal going to the CRT tube is intercepted and replaced with the audio output signal from the virtual assistant, fed through an amplifier. This makes the horizontal line on the screen react dynamically to the sound waves.
0:05:34 Animatronic Eyes: An eye mechanism is built using a 3D-printed design by Will Cogley (Millheim Mechatronics), controlled by an Arduino and multiple servo motors.
0:06:28 Power Issues: Initial tests show the eye servos are jittery, suspected to be caused by an underpowered buck converter (3A limit) supplying the six servos.
0:07:08 Face Tracking: A "Person Sensor" from Useful Sensors is implemented. This small camera module allows the animatronic eyes to track a user's face, enabling the creature to maintain eye contact and appear more interactive and aware.
0:08:13 Alexa Wake Word Challenge: The creator identifies a limitation: Alexa only processes commands after the wake word, but doesn't provide an immediate output upon hearing the wake word. This prevents instant reactions like eye movement when called.
0:08:54 Wake Word Hack: The Amazon Echo device is disassembled, and the circuit controlling the LED light ring (which activates on the wake word) is identified. The voltage change on the LED signal pads is tapped into and fed to a microcontroller, allowing it to detect the wake word instantly.
11:09 Eyeball Creation Failure: An attempt to create realistic eyeballs by casting 3D prints in resin fails when heating the resin to remove bubbles warps the delicate prints, making them unusable with the mold.
12:26 Chassis Construction: Inspired by an old Apple II computer with a clear top panel, a custom chassis is designed using laser-cut clear acrylic sheets to house all the disassembled components (CRT board, Echo, animatronics, power supplies, Arduino).
15:25 Final Assembly: All components are integrated into the multi-layered acrylic chassis, including the animatronics, person sensor, amplifiers, power converters, CRT board, Arduino, servo board, and the rehoused Amazon Echo device.
17:22 Demonstration: The completed project, named "Alexatron," is turned on. It demonstrates eye tracking, voice visualization on the CRT screen, and responds to voice commands via the hacked Alexa.
18:11 Reflection and Issues: The creator notes it was a very complex build with significant troubleshooting. The final prototype is functional but has flaws, including noisy/jittery servos and a speaker hum.
18:45 Future Improvements: The main suggested improvement is to replace the underlying Alexa platform with a GPT-based AI to enable much richer and more dynamic interactions.