Hardware Assembly Guide

Estimated Time: 2-3 hours | Difficulty: Intermediate

Kit Checklist

Category Component Quantity ✓
Mechanical Parts Delta Robot Arm 1 □
Aluminum Frame Base (2020) 1 □
3D-Printed Upper Arms (150mm) + Metal Lower Linkages (281mm) 6 □
Ball Joints 12 □
End Effector Mounting Plate 1 □
Electronic Components ESP32 Development Board 1 □
NEMA17 Stepper Motor (1.8°) 3 □
A4988 Driver Board 3 □
12V 3A Power Adapter 1 □
USB Data Cable 1 □
Terminal Blocks/Dupont Wires 1 set □
Pneumatic System 12V Vacuum Pump 1 □
Solenoid Valve 1 □
Suction Cup (Ø20mm) 1 □
Pneumatic Tubing 2m □

Tool Preparation

Required Tools

  • Phillips Screwdriver (PH2)
  • Hex Key Set (1.5-5mm)
  • Wire Cutters
  • Wire Strippers
  • Multimeter (voltage/continuity test)

Optional Tools

  • Heat Gun (for heat shrink tubing)
  • Soldering Station (if soldering required)
  • Digital Calipers (precise measurement)
  • Label Printer (cable marking)

Assembly Steps

Step 1: Base Assembly

Base Assembly
  1. Build base frame using aluminum extrusions
  2. Install three motor mounting plates (120° evenly distributed)
  3. Ensure base is level and stable

Step 2: Motor Installation

Motor Installation
  1. Mount 3 NEMA17 motors to the base
  2. Install gears (gear ratio 4.5:1)
  3. Ensure motor shaft aligns with base center
⚠️ Important: Motor orientation matters, ensure output shaft faces upward.

Step 3: Arm Assembly

Arm Assembly
  1. Connect upper arm (150mm) to motor output shaft
  2. Connect lower arm (281mm) to upper arm ball joint
  3. Repeat 3 times to assemble 3 arm sets
  4. Ensure ball joints move smoothly

Step 4: End Effector

End Effector
  1. Connect 3 lower arms to end effector platform
  2. Install suction cup mount (50mm offset)
  3. Connect pneumatic tubing to suction cup

Step 5: Pneumatic System

  1. Mount vacuum pump to base
  2. Install solenoid valve
  3. Connect air path: pump → valve → suction cup
  4. Ensure tubing connections are secure with no air leaks

Wiring Guide

⚠️ Power Off: Ensure all power is disconnected during wiring!

ESP32 Pin Assignment Table

Function ESP32 Pin Connect To
Motor X (A-axis)
Step Pulse GPIO 14 A4988 STEP
Direction GPIO 27 A4988 DIR
Endstop GPIO 36 Limit Switch (X_MIN)
Motor Y (B-axis)
Step Pulse GPIO 26 A4988 STEP
Direction GPIO 25 A4988 DIR
Endstop GPIO 39 Limit Switch (Y_MIN)
Motor Z (C-axis)
Step Pulse GPIO 33 A4988 STEP
Direction GPIO 32 A4988 DIR
Endstop GPIO 34 Limit Switch (Z_MIN)
Shared / Peripherals
Motor Enable GPIO 12 A4988 ENABLE (3x shared)
Vacuum Pump GPIO 21 Pump Control
Solenoid Valve GPIO 16 PWM Valve Control
Conveyor Step GPIO 2 Conveyor Motor STEP (PWM)
Conveyor Dir GPIO 15 Conveyor Motor DIR
Conveyor Enable GPIO 4 Conveyor Motor ENABLE

Complete Wiring Diagram

Complete Wiring

Complete system wiring diagram (click to enlarge)

ESP32 Pinout

ESP32 detailed pinout diagram

Wiring Precautions

  • Power Polarity: Verify +12V and GND connections
  • Motor Phase: Don't reverse A4988's 1A/1B/2A/2B
  • Logic Level: ESP32 outputs 3.3V, A4988 accepts this
  • Common Ground: ESP32 and power GND must be connected
  • Relays: Use optoisolated relays (recommended)

Initial Power-On Check

1. Pre-Power Check

2. Power-On Test

  1. Connect 12V power supply
  2. ESP32 onboard LED should light up (blue or red)
  3. A4988 indicator LEDs should light up (green)
  4. Touch A4988, should be slightly warm (not hot)

3. Motor Enable Test

# Send command via serial port
M17    # Enable motors

# Motors should now lock (resistance when turned by hand)

M18    # Disable motors

# Motors should now release (free rotation)
✅ Check Passed

If all LEDs are normal and motors can enable/disable, hardware connections are correct!

→ Continue: Software Installation