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This page provides a comprehensive overview of all hardware components required to build the autonomous robotic arm system with computer vision capabilities.

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Core Computing Units

Raspberry Pi

Model: Raspberry Pi 4 (recommended) or Raspberry Pi 5Purpose: Main computing unit for vision processing, AI inference, and high-level controlKey Features:
  • Runs Python-based control system
  • Handles camera input and YOLO object detection
  • Serial communication with VEX Brain
  • Supports OpenCV and PyTorch libraries

VEX IQ Brain (Gen 2)

Model: VEX IQ Brain 2nd GenerationPurpose: Real-time motor control, sensor management, and low-level operationsKey Features:
  • MicroPython programming support
  • 12 smart ports for sensors/motors
  • Built-in inertial sensor
  • Serial communication via /dev/serial1

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Vision System

USB Camera

Specifications:
  • Resolution: 1280x720 (720p minimum)
  • Interface: USB 2.0 or higher
  • Frame rate: 30fps recommended
  • Compatible with OpenCV (cv2.VideoCapture)
Configuration (from camera/main.py:6-9):
camera_index: int = 0
width: int = 1280
height: int = 720
Software Requirements:
  • opencv-python==4.11.0.86
  • Supports real-time object detection during scanning

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VEX Robotics Components

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Motors

Base Motor

Port: PORT1Function: Rotates the entire arm for 360° scanningControl: Position control using inertial sensor feedbackSee vex_brain/src/main.py:171

Shoulder Motor

Port: PORT2Function: Controls vertical arm movementConfiguration: Max torque 95%Safety: Bumper sensor integration for collision detectionSee vex_brain/src/main.py:172

Elbow Motor

Port: PORT3Function: Extends/retracts arm reachConfiguration: Max torque 95%See vex_brain/src/main.py:173

Gripper Motor

Port: PORT4Function: Opens and closes gripper for object manipulationControl: Current-based grip detection (0.3-0.5A thresholds)See vex_brain/src/main.py:174,244

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Sensors

Gripper Distance Sensor

Port: PORT7Type: VEX Distance SensorRange: 0-40mm detection range for pick operationsPurpose: Detects when gripper is close enough to grasp objectsSee vex_brain/src/main.py:67

TouchLED

Port: PORT8Type: VEX TouchLEDPurpose: Visual status indicatorColors:
  • Red (255,0,0): Error/Stop
  • Orange (255,150,0): Warning
  • Green (0,255,0): Ready
  • Blue (0,0,255): Running
  • White (255,255,255): Initialization
See vex_brain/src/main.py:17-23,68

Base Distance Sensor

Port: PORT9Type: VEX Distance SensorRange: 50-345mm for environment scanningPurpose: Detects objects during 360° base rotation scanSee vex_brain/src/main.py:69

Bumper Sensor

Port: PORT10Type: VEX Bumper SensorPurpose: Safety collision detection for shoulder jointFunction: Triggers emergency stop and reverse movementSee vex_brain/src/main.py:70,226

Inertial Sensor

Built-in: VEX IQ BrainPurpose: Provides absolute heading for base rotationFunction: Enables precise angle positioning (0-360°)See vex_brain/src/main.py:66,81-82

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Connectivity

Serial Communication Cable

Connection: Raspberry Pi USB ↔ VEX BrainInterface:
  • Raspberry Pi: /dev/ttyACM1 (USB CDC)
  • VEX Brain: /dev/serial1
Protocol: JSON messages over serial at 115200 baudConfiguration (from communication/serial_manager.py:18-24):
port: str = '/dev/ttyACM1'
baudrate: int = 115200

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Power Requirements

Both the Raspberry Pi and VEX Brain require separate power supplies:
  • Raspberry Pi: 5V 3A USB-C power supply
  • VEX Brain: VEX IQ Battery (rechargeable)

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Software Dependencies

Key Python packages required (from requirements.txt): 
opencv-python==4.11.0.86      # Camera interface
pyserial==3.5                  # Serial communication
torch==2.6.0                   # AI inference
ultralytics==8.3.77           # YOLO model
ncnn==1.0.20241226            # Optimized inference
numpy==1.24.2                 # Array operations

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Assembly Notes

1

VEX Arm Assembly

Follow VEX IQ robotics building instructions for mechanical assembly of the 4-DOF arm
2

Sensor Installation

Install all sensors in their designated ports as specified above
3

Camera Mounting

Mount USB camera with clear view of the workspace, connect to Raspberry Pi USB port
4

Verify Connections

Run the check service to verify all motors and sensors are properly installed:
# From main.py interface
# Press 'c' for check service

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Next Steps

VEX Brain Setup

Learn about VEX Brain programming and configuration

Sensor Configuration

Detailed sensor setup and calibration

Wiring Diagram

Complete wiring and connection guide

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