OmArm One: 6+1 DOF Robot Arm on Real Ball Bearings – CAD, Firmware, BOM & Build Guide (Part 1)

الوصف

ما هو مدرج

• 23 STL files – every printed part, numbered and print-ready
• Bambu Studio project (.3mf) – both print plates with orientation, seams and supports already set (~15 h total)
• STEP assembly + Fusion 360 source (.f3d) – full parametric CAD for your own modifications
• A1 assembly drawing + BOM Excel – ballooned drawing; the BOM item numbers match the balloons 1:1
• الإلكترونيات – wiring diagram, Fritzing source and electronics BOM (ESP32 + PCA9685 + 6× DS3240 + SG90)
• ESP32 firmware – web-app control with quintic motion profiles, a safety layer that never moves blind after a reset, sequence editor, PWA served by the arm itself (no app, no cloud, no router)
• Unit tests – motion, command flow and servo-map tests you can run on your PC without hardware
• 99-page PDF build guide – requirements, torque analysis, bearing architecture, 16 assembly steps with images, wiring, first power-up, payload test, troubleshooting and FAQ

Specifications

• 6 joints + parallel-jaw gripper · 485 mm reach
• 200 g nominal / 250 g maximum payload at a 300 mm radius (measured: 325 g held)
• Every loaded joint runs on steel ball bearings: SKF 51110 + 6806ZZ in the base, 695ZZ at the pitch joints, 6806ZZ at the forearm roll
• 6× DSSERVO DS3240-180 (36 kg·cm @ 5 V) + 1× SG90 · ESP32 + PCA9685 @ 250 Hz

Watch and read first

• Build video: YouTube – OmArm One Part 1
• Full written guide: the blog post (free, with every calculation derived)

This is Part 1 of a 5-part series — Part 2 gives the arm a digital twin in ROS 2, Part 3 adds MoveIt 2 motion planning, Part 4 computer vision, Part 5 marker-free grasping.

License

For personal, non-commercial use only. You may print, build and modify everything for your own projects. Redistribution, resale or sharing of the files (original or modified) is not permitted.