Most of the month was Easter. The wiring for the Stepper Motor was done, as well as another prototype.
An ongoing issue with the Stepper Motor was that it would quickly cause the Hardware to overheat to a dangerous degree – even the addition of a heat sink did not remedy this issue. This is because the NEMA17 Stepper Motor used does not work well with the Arduino Motor Rev Shield 3. This is because the Nema 17 has an extremely low coil resistance of around 2 ohms per winding, which means that if supplied with constant voltage without active current limiting, it will draw too much power. This forces the L298 Driver found in the Arduino Motor Rev Shield to go beyond its limits, causing it to overheat and eventually burn out. This would be remedied by using a “High Impedence Motor” such as a small 5v reduction stepper, with a far higher resistance of over 40 ohms per winding, which reduces the current down to safe levels that the L298 can handle.
If I chose to swap to a High Impedence Motor, it would however have downsides. The maximums peed and torque would be significantly decreased, as the higher resistance limits the current flowing through the coils. Additionally, torque decreases as speed increases as the current does not have time to travel before the next step.
Overall, there were two primary options. The first is to simply upgrade my driver to one such as the A4988, which actively limits current so would allow it to be ran safely. The other choice would be to simply switch to a high impedance motor, accepting the decreases’ function – however for a project such as this which only requires slow speeds, it may not have any visible impact on the result.
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