3D-Printed Parallel Gripper / SO-ARM 100

A precision parallel gripper designed by Robonine for robotics applications, featuring 3D-printed components and professional servo control using Feetech STS3215 servos.

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Questions? We're here to help!
📩 Email: [email protected]

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📸 Gallery

Assembled Gripper

Real-world implementation of the gripper

3D CAD Design

3D CAD design showing internal mechanism

🎥 See It in Action

Click above to see the parallel gripper working with precise control and smooth operation

💰 Total Project Cost

Complete Build Cost: $69.45-74.45 (Amazon pricing)

Category	Cost (USD)
Electronic Components	$39.98
Mechanical Components	$22.87
3D Printing Materials	$5-10
Fasteners	$1.60
Total	$69.45-74.45

All components available on Amazon with direct purchase links in Bill of Materials

🎯 Project Overview

This project provides a complete open-source solution for a parallel gripper that can be integrated with robotic arms. The gripper features:

• Precision Control: Servo-driven parallel jaw mechanism with real-time feedback
• Professional Design: Industrial-grade part numbering and assembly procedures
• Cost-Effective: 3D-printed components with readily available hardware
• Versatile Integration: Compatible with various robotics platforms

🔧 Key Features

• Parallel Jaw Movement: Ensures consistent grip on objects of various sizes
• Real-time Monitoring: Current, voltage, temperature, and load feedback
• Precise Positioning: Degree-based control with position feedback (±0.1°)
• Robust Construction: Linear bearings for smooth, reliable operation
• Professional Design: CAD design with industrial-grade components
• Servo Control: High-torque Feetech STS3215 with bus communication
• 3D Printable: All mechanical parts designed for standard FDM printers
• Open Source: Complete documentation, code, and CAD files included

📋 Specifications

• Servo: Feetech STS3215 (compatible with Waveshare variants)
• Communication: Serial (RS485/TTL, up to 1Mbps)
• Power: 6-12V DC
• Jaw Travel: Configurable based on gear ratio
• Materials: PLA/PETG 3D printed parts, steel rods, precision bearings
• Positioning Accuracy: ±0.1° (4096 steps/360°)
• Force: Up to 15kg·cm servo torque
• Response Time: <100ms for small movements

🎯 Performance Highlights

✅ Smooth Operation - Linear bearings ensure frictionless movement
✅ Precise Control - Degree-based positioning with real-time feedback
✅ Reliable Gripping - Parallel jaws maintain consistent contact
✅ Professional Integration - Bus communication for robotics systems
✅ Proven Design - Tested and demonstrated in real applications

🛠️ Hardware Requirements

Electronic Components

• 1x Feetech STS3215-C018 Servo Motor or Waveshare STS3215
• 1x Bus Servo Adapter Board (Waveshare or compatible)

Mechanical Components

• 2x MR106ZZ Bearings (10x6x3 mm)
• 4x LM6UU Linear Bearings (12x6x19 mm)
• 2x Stainless Steel Rods (6mm diameter, 150mm length)

3D-Printed Parts

• 1x Main Frame (RB9.01.060.010)
• 2x Clamps (RB9.01.060.020)
• 2x Gear Racks (RB9.01.060.030)
• 1x Drive Gear (RB9.01.060.040)

Fasteners

• 4x M3x10 DIN 7991 screws
• 4x M3x20 DIN 7991 screws
• 2x M4x8 DIN 7991 screws
• 4x M3 DIN 934 nuts
• 4x Self-tapping screws (included with servo)

🚀 Quick Start

1. Print the Parts: Use the STL files in /hardware/3d-models/
2. Gather Components: Order parts from the Bill of Materials
3. Assembly: Follow the Assembly Guide
4. Software Setup:
   • Download and install the STServo SDK:
     • Download STServo Python SDK
     • Extract the ZIP file and copy the STservo_sdk folder to software/python/ directory
   • Install Python dependencies and run the control software:

pip install -r software/python/requirements.txt
python software/python/gripper_control.py

📁 Repository Structure

├── docs/                    # Documentation
│   ├── assembly-guide.md   # Step-by-step assembly
│   ├── bom.md             # Bill of materials
│   └── specifications.md   # Technical specifications
├── hardware/
│   └── 3d-models/         # STL files for 3D printing
├── software/
│   └── python/            # Control software
└── examples/              # Usage examples

🤝 Contributing

We welcome contributions! Please see our contributing guidelines for:

• Bug reports and feature requests
• Code contributions
• Documentation improvements
• Hardware modifications

📄 License

This project is licensed under the GPL-3.0 license - see the LICENSE file for details.

🔗 Links

• Feetech STS3215 Servo
• Waveshare Bus Servo Adapter
• Project Documentation

📞 Support

For questions and support:

• Open an issue on GitHub
• Check the documentation in /docs/
• Review the examples in /examples/

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Built for the robotics community by Robonine 🤖

Questions? We're here to help!
📩 Email: [email protected]