Motorized Lifting Platform
I designed this lifting platform to upgrade my grandparents’ mid-century, teak record cabinet. It uses a pair of stepper motor-driven linear actuators to lift a record player up and down with a sinusoidal velocity profile, minimizing sudden changes in acceleration which could cause records to skip. A system of pulleys multiply the force of the actuators, allowing two small Nema 17 motors to lift up to 20 pounds reliably.
It uses a capacitive touch sensor to activate up/down motion, and the actuator’s slim profile allows it to nest into the sides of the cabinet, leaving room for AV equipment in the middle. Tabbed latch mounts allow for easy removal of the platform for better access to the internal volume of the cabinet and 0.5mm shims are be used to level the platform.
Each actuator features linear bearings for smooth, reliable motion and a screw-driven belt-tensioning system.
The pulley layout is functionally a 2:1 pulley system but with a mirrored loop to create a pulley system with a fixed length belt and no slack.
A capacitive touch sensor is embedded into a 3D printed housing in place of a traditional button to improve aesthetics and ease of use.
Each linear actuator assembly consists of seven 3D printed parts and 52 off-the-shelf components comprised of bearings, pulleys, linear rods, a Nema 17 stepper motor, and fasteners.
An ESP32 microcontroller is used to control the stepper motor drivers.