The original system employed the use of the Greartisan 12V brushed motor rated at 100rpm. The system was designed to have an input crank link with a D-shaft cutout matching the motor shaft's cross section profile itself.
The motor is rated at 12V and 1.1A, and so the theoretical max power is given by P = VI, or about 13.2W. At 100rpm, by using the relation of P = Tω and rearranging, the no load motor torque at 100rpm is 1.2605 Nm. The images below describe the motor visually and by specification..
Greartisan 12V brushed motor image and specifications
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PWM reduces both torque and speed, and in doing so, no combination was safe for the system's structural integrity or optimal to push the slider against the tension in the rubber bands. The motor kept stalling when attempting to pull back the slider and the system pauses and remains stationary. Therefore, a switch to a hand driven layout would enable more testing and operation until a more viable solution is obtained (see Conclusions conclusions and future works).
GIF depicting Motor Stall due to massive load.
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