A 3D-printed robotic end effector designed and programmed as part of a team project to automate warehouse order packaging. The system integrates a Python-based ordering pipeline with a physical gripper mechanism driven by a servo motor and operated via a Q-arm robot controlled by a Raspberry Pi 4.
Timeline: October – December 2025
Platform: Python | Raspberry Pi 4 | Q-arm | CAD (PrusaSlicer)
Type: Team project — personal contributions listed below
Global warehouses process thousands of packages daily and require systems that can package and organize items without manual labor, reducing operational costs and workplace injuries.
The team coded 7 functions covering the full ordering pipeline: account creation, order retrieval, order verification, purchase history storage, receipt generation, item indication, and physical packing via the Q-arm.
The end effector was designed to attach to the Q-arm's servo motor and physically pick up items of varying shapes and sizes, dropping them into designated parcel locations based on scanner input.
Software
sign_up()— secure user authentication function using hashed passwords (bcrypt) and unique UserID generation to manage warehouse ordering datapack_products()— core packing function with helper functions (witchhat,bowl) that take scanner input and direct the Q-arm to pick up and deliver the correct items
Hardware & CAD
- Designed the main gear, sized to match the torque output of the servo motor and supply it to the end effector
- Created the full assembly exploded view drawing, documenting part positions, quantities, and part numbers
- Contributed to code integration and the testing plan
- Raspberry Pi 4
- Q-arm robot
- Servo motor
- 3D-printed end effector (PLA, PrusaSlicer)
- Main gear + sliding arm gripper mechanism
Parts list: End Effector Platform, Main Gear, Arms (×2), Sliders (×2), 92000A126 Passivated 18-8 SS Pan Head Screws (×4)
One week before the deadline, testing revealed the arm width was too wide, causing the effector to knock adjacent items during pickup. The team resolved this by shortening the arm width and increasing the length and depth of the arm tips to maintain contact with the target item without disturbing neighbors. Multiple reprints were required to land on the final geometry.
- Add precise Q-arm speed and direction control to compensate for mechanical imperfections
- Reduce Q-arm travel by eliminating the home-position return after each delivery cycle
- Implement a locking mechanism on the clamp — the servo motor currently loses torque on contact, reducing grip force
- Widen item spacing in the platform design to reduce toppling during packing