sg90s-Lifter

I. Inspiration

Drawing inspiration from the structure of small linear lifting modules, this design uses an SG90S micro servo as its power source and employs a rack-and-pinion transmission system. It is specifically engineered for DIY robotics projects and desktop lifting experiment setups, providing a clear demonstration of the mechanical principles behind rack-and-pinion motion, making it ideal for hands-on STEAM education and training.

II. 3D Printing Requirements

The frame and rack are printed using PLA filament, while the gears are preferably made with PETG to enhance wear resistance. All parts feature a uniform wall thickness of 2 mm, with guide post holes pre‑drilled to allow for a +0.1 mm assembly clearance. The design avoids large overhanging structures, requiring only minimal support on the small arc-shaped edges at the top of the rack.

III. Hardware and Structure

Four metal linear shafts serve as vertical guides, while the servo drives a gear that engages with the rack, enabling smooth vertical movement of the top plate. The base includes a dedicated mounting slot for the servo, allowing integration with a microcontroller to program and control the lifting stroke. This makes it an excellent introductory DIY kit for learning mechanical transmission principles.