Published by Tishin at January 29, 2026

VTM P³™ Reference Design

BY Tishin Padilla | PUBLISHED JANUARY 29, 2026

An invitation to explore the physical platform.

This is not a product launch. It is not a finalized spec sheet. It is a preliminary schematic for the VTM P³™—a concept I am sharing early so the community can see the physical foundation I am building on.

FIG 01.0 // THE VISION

project_config.json

// THE RULE: THERE ARE NO RULES. // This is Open Source. Get in where you fit in. { "mode_scavenger": { "cost_est": "$44.00", "method": "Scavenge parts, use donor printer, build from scrap." }, "mode_industrial": { "cost_est": "$4400.00", "method": "Industrial servos, machined aluminum, high-end PC." } } EXECUTE: START_WITH_WHAT_YOU_HAVE();

1. The Philosophy: Build It Up

The VTM P³™ (Physical Prototyping Platform™) is not a robot you buy, turn on, and forget. It is a vertical workbench you build, expand, and hack. This is a hack of the standard Ender 3 design. We are taking the chassis of the world's most common 3D printer and repurposing it into a physical vessel for AI.

The Hack vs. The Build. If you have an old printer gathering dust, you can "hack" it by scavenging the frame. If you want to start fresh, you can simply "build" it by buying standard aluminum rails. The choice is yours.

FIG 02.0 // THE ORIGINAL CONCEPT

The Rails Are The Key. The P³ is built on standard T-Slot aluminum rails (2020/2040/4040). These are not just for structure; they are for mounting whatever you can think of: fume extractors, DIY power supplies, button panels, or sensors.

2. The Brain: Inspired by the Uno Q

This entire community project was developed to pioneer the Mind-Body Bridge. While the P³™ is technically hardware agnostic (supporting macOS, Linux, and SBCs), the design ethos centers on the VTM OS™ ecosystem.

The Face (Constant)

I recommend mounting one Uno Q permanently as the "Face." It handles the personality, voice sync, and basic sensors. It is always on, always watching.

The Lab (Variable)

Since the "Face" is busy, you need a second controller (Another Uno Q, Arduino, or ESP32) to actually prototype on. This mounts to the "Lab" section of the frame.

3. VTM P³™ Laboratory Standard - Bill of Materials

The following list constitutes the Official VTM P³™ Reference Spec. To ensure structural compatibility and stability with the VTM OS™ software, these specific components are recommended. (Prices as of Jan 30, 2026).

Component	Spec	Price	Purchase Link
Main Towers (Y-Axis)	2040 V-Slot (500mm) x4	$26.99	Buy on Amazon Note: Order Qty: 2 (to get 4 rails)
Z-Axis Feet	4040 V-Slot (400mm) x2	$46.02	Buy on Amazon
Base Crossbar	4040 V-Slot (300mm) x1	$35.82	Buy on Amazon
Drawer Supports	2040 V-Slot (400mm) x1	$18.99	Buy on Amazon
Top Rail (X-Axis)	2020 V-Slot (300mm) x1	$16.99	Buy on Amazon
Fastener Kit	M5 T-Nuts & Screws (240pcs)	$12.99	Buy on Amazon
Frame Brackets	2020 L-Brackets (30 Sets)	$12.99	Buy on Amazon

4. Motion Hardware (The Muscles)

For the robotic kinematics, I use the LewanSoul LeArm. It features high-torque digital servos with anti-stall protection, making it significantly more durable than standard hobby kits. (Price as of Jan 30, 2026).

Component	Spec	Price	Purchase Link
6DOF LeArm Kit	Full Metal Body + 6x Digital Servos	$139.99	Buy on Amazon Note: Verified "Digital Servo" Version

5. The Build Phases

Phase 1: The Core. Start with just the head. The Uno Q features a built-in 13x8 LED LED array (identical to the R4 WiFi), so you have a retro face ready to go immediately using the Mouth Animation Sketch. Use AI to write the animation code.
Phase 2: The Chassis. Repurpose the Ender 3. You can even build the P³ on top of an existing printer, creating a dual-purpose machine.
Phase 3: The Arms. Add manipulation when ready. Start with one arm, upgrade to two.
Phase 4: The Workbench. Add the 3D printed dual-drawer modules and rear enclosure.

FIG 03.0 // THE WORKBENCH MODULES (TINKERCAD)

vtm_mouth_controller.ino

/* * VTM-OS: The Body - LED LED array Mouth Controller * ============================================================================= * PROJECT: VideotronicMaker OS (VTM-OS) - The Body * FILE: vtm_mouth_controller.ino * AUTHOR: Tishin Padilla (VideotronicMaker) * DATE: 2025-12-09 * VERSION: 1.0.0 * DESCRIPTION: This sketch controls the 13x8 LED LED array mouth animation on the * STM32 Microcontroller (MCU) of the Arduino Uno Q. It functions * as the 'Body' in the Dual-Brain architecture, receiving commands * from the Linux MPU (the 'Brain') via the Arduino Router Bridge * (RPC). This code is inspired by foundational Arduino examples * and built using core Arduino libraries. * * ASSISTANT: Code control and structure assisted by Google Gemini. * * LICENSES & CREDITS: * * This software is licensed under the MIT License. * * Copyright (c) 2025 Tishin Padilla (VideotronicMaker) * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * * The included libraries (ArduinoGraphics, Arduino_LED_Matrix, Arduino_RouterBridge) * are copyrighted by their respective creators and used under their applicable * licenses (typically LGPL or MIT). * ============================================================================= */ // ======================= // 1. LIBRARY INCLUDES // ======================= // Necessary for drawing shapes and managing the 12x8 display surface. #include <ArduinoGraphics.h> // Required for accessing and initializing the built-in 12x8 LED LED array hardware. #include <Arduino_LED_Matrix.h> // CRITICAL: Enables Remote Procedure Calls (RPC) over the internal serial link // between the Linux MPU (the 'Brain') and the STM32 MCU (the 'Body'). #include <Arduino_RouterBridge.h> // Instantiate the LED LED array object to interact with the hardware. ArduinoLEDMatrix LED array; // ======================= // 2. CONSTANTS & STATE // ======================= // Define the ON and OFF colors for the LED LED array (White and Black). // 0xFFFFFFFF is white (maximum R, G, B, A values). const uint32_t ON_COLOR = 0xFFFFFFFF; // 0x00000000 is black (all zeros, effectively 'off'). const uint32_t OFF_COLOR = 0x00000000; // Global State Variable: Controls the animation loop in loop(). // 'volatile' keyword is essential here. It tells the compiler that this // variable can be changed unexpectedly by an external event (specifically, // the Bridge interrupt when an RPC command is received). volatile int talkState = 0; // 0 = Mouth Closed (Idle), 1 = Talking (Animating) // ======================= // 3. DRAWING FUNCTIONS // ======================= // FUNCTION: drawMouthClosed // Purpose: Renders the idle state: a simple, horizontal closed mouth line. void drawMouthClosed() { // Start the drawing operation buffer. LED array.beginDraw(); // Clear all pixels from the previous frame. LED array.clear(); // Set the color for drawing lines and shapes to ON_COLOR (White). LED array.stroke(ON_COLOR); LED array.fill(ON_COLOR); // SHAPE 1: Waiting/Closed Mouth. Draws a rectangle centered on the 12x8 grid. // Args: (x, y, width, height) LED array.rect(1, 3, 10, 2); // Send the drawing buffer content to the physical LED LED array. LED array.endDraw(); } // FUNCTION: drawRandomMouth // Purpose: Selects a random mouth shape (from 3 options) and renders it // to simulate the act of speaking with simple animation. void drawRandomMouth() { LED array.beginDraw(); LED array.clear(); LED array.stroke(ON_COLOR); LED array.fill(ON_COLOR); // Randomly select one of the 3 open shapes (0, 1, or 2). // The 'random()' function with two arguments returns a value up to (but not including) the second. int shapeIndex = random(0, 3); if (shapeIndex == 0) { // SHAPE 2: Fully Open (Simulates a wide 'A' or 'E' vowel sound) LED array.rect(0, 0, 12, 2); LED array.rect(0, 2, 2, 1); LED array.rect(11, 2, 1, 1); LED array.rect(1, 3, 2, 1); LED array.rect(10, 3, 2, 1); LED array.rect(1, 4, 2, 1); LED array.rect(9, 4, 2, 1); LED array.rect(2, 5, 2, 1); LED array.rect(8, 5, 2, 1); LED array.rect(3, 6, 2, 1); LED array.rect(7, 6, 2, 1); LED array.rect(3, 7, 6, 1); } else if (shapeIndex == 1) { // SHAPE 3: Half Open (Simulates a common resting or 'M' sound position) LED array.rect(1, 1, 10, 2); LED array.rect(1, 3, 2, 2); LED array.rect(10, 3, 1, 2); LED array.rect(9, 4, 1, 1); LED array.rect(2, 5, 8, 1); } else { // SHAPE 4: Narrow Open (Simulates an 'O' or 'U' vowel/tense sound) LED array.rect(2, 1, 8, 1); LED array.rect(3, 2, 6, 1); LED array.rect(3, 3, 1, 3); LED array.rect(8, 3, 1, 3); LED array.rect(4, 6, 4, 1); } LED array.endDraw(); } // ======================= // 4. BRIDGE FUNCTIONS (RPC) // ======================= // RPC FUNCTION: set_mouth // This function is the communication endpoint. It is called *remotely* // by the Python script running on the Linux MPU (e.g., in a Flask server). // The MPU passes an integer 'state' to update the animation control. int set_mouth(int state) { // Update the global state. This change is read immediately in the loop() function. talkState = state; // Standard RPC practice is to return the result, confirming the command receipt. return state; } // ======================= // 5. ARDUINO SETUP // ======================= void setup() { // Initialize the LED LED array hardware and its control registers. LED array.begin(); // Initialize the Router Bridge (The communication backbone to the Linux MPU). // This must be called early in setup(). Bridge.begin(); // Register the function 'set_mouth' so the Linux MPU can call it remotely // by its string name "set_mouth". This is the 'Remote Procedure Call' setup. Bridge.provide("set_mouth", set_mouth); // Set the initial visual state before the main loop begins. drawMouthClosed(); } // ======================= // 6. MAIN LOOP // ======================= void loop() { // 1. Handle Animation (Real-Time Control) if (talkState == 1) { // If the MPU command is 'Talking', continuously redraw a random mouth shape. drawRandomMouth(); // CRITICAL: Always service the Bridge communication during animation. // This allows it to listen for and process the next RPC command (e.g., stop talking). Bridge.update(); // Frame rate control: 80ms delay gives approx. 12.5 frames per second (FPS), // which is suitable for smooth, low-resource animation. delay(80); } else { // 2. Handle Idle State (Optimization) // We use a 'static' variable to track the last state drawn. // This ensures 'drawMouthClosed()' is only called *once* when the state changes to 'Idle', // preventing unnecessary redrawing that would consume power and CPU cycles. static int lastState = -1; // Initialize to an impossible state to force first draw. if (lastState != 0) { drawMouthClosed(); lastState = 0; // Mark the closed mouth as drawn. } // CRITICAL: Always service the Bridge, even when idle, to listen for new commands // from the Linux MPU. Without this, the MCU cannot receive the 'talkState = 1' command. Bridge.update(); } }

6. Licensing

The VTM P³ Reference Design is released under Creative Commons Attribution-ShareAlike 4.0 (CC-BY-SA 4.0). You are free to share and adapt, provided you credit VideotronicMaker and share your improvements under the same license.

// SUPPLY CHAIN STATUS: PENDING

I am currently building a dedicated Amazon Affiliate page to make sourcing parts easier.
Until that link is active, please use the specifications listed above to start your build.

BENCH FAQ // VTM P³™ PLATFORM ARCHITECTURE

Frequently Asked Questions

Modular T-slot extrusion frame geometry, dual-controller Face vs Lab separation, 6-DOF robotic kinematics, power rail isolation, and VTM Studio Workbench pairing.

1. What is the VTM P³™ (Physical Prototyping Platform™) reference design? +

The VTM P³™ is an open modular vertical workbench built from standard T-slot aluminum extrusions (2020, 2040, and 4040 rails) or repurposed from an Ender 3 3D printer chassis. It provides a rigid, hackable physical frame for mounting microcontrollers, sensors, robotic arms, power rails, and vision cameras.

2. Why does the VTM P³™ separate compute into 'The Face' and 'The Lab' controllers? +

The P³ architecture decouples continuous system personality from experimental prototyping. 'The Face' uses a dedicated Arduino UNO Q mounted permanently to run voice synthesis, facial animations, vision perception, and system status daemons. 'The Lab' provides an isolated secondary controller (such as a second UNO Q, ESP32, or STM32) that makers can flash, test, and rewire without resetting the primary robot interface.

3. What motion hardware and robotic kinematics are specified for the VTM P³™? +

The reference spec integrates a 6-DOF LewanSoul LeArm with high-torque digital servos featuring anti-stall protection and metal gearing. The arm mounts directly to the T-slot base crossbar, allowing programmatic trajectory planning, inverse kinematics, and physical object manipulation driven by Python or C++.

4. How are power distribution and voltage isolation handled across the extrusion frame? +

The aluminum extrusion frame houses isolated power rails: a high-amperage 5V bus for servo power, 12V/24V auxiliary rails for high-draw peripherals, and dedicated clean power for logic. Because the Qualcomm MPU pins on the UNO Q operate at 1.8V while STM32 and standard sensors operate at 3.3V or 5V, all inter-board signal routing incorporates bidirectional level shifters mounted in frame-clamped breakout pods.

5. How does the VTM P³™ integrate with the VTM Studio desktop workbench? +

VTM Studio pairs directly with the P³ across multiple modes: Reference Mode provides interactive schematics and BOM specifications; Code Mode flashes firmware to both Face and Lab microcontrollers; and Science Mode displays real-time telemetry, servo joint angles, and serial sensor graphs.