Servo gear rack mechanism Servo motor gear rack mechanism MG90S SG90

Build Overview

This is an ingenious linkage mechanism born from the interaction of a servo and a rack and pinion system. With its rotational and linear movements, turning and pushing, it fully embodies the beauty of mechanics
When paired with a 180° SG90 servo, the gear rotates half a turn, smoothly advancing the rack. It achieves a travel distance of approximately 30.16 mm, ensuring precise positioning and controlled extension and retraction

When paired with a 360° SG90 servo, the gear completes a full rotation, continuously driving the rack forward. It achieves a travel distance of approximately 60.32 mm, delivering continuous power and relentless forward motion
If the servo rotates non-stop, the gear will engage continuously, theoretically enabling infinitely long linear motion—as long as the rack is sufficiently long and the bracket is stable enough. Otherwise, it will truly run wild and "run" directly to the ground

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