Turntable photography has seen a rise in popularity driven by online shopping. If you can’t hold it in your hand at least you can see what it looks like from all angles. From the still image, [Petteri Aimonen's] roll-your-own turntable looks great. It’s completely enclosed and has a very nice paint job. But when you see it in action it appears to suffer from a stutter.
He isn’t just using this to capture continuously rotating video, but planned to have it rotate a set amount and then pause while an image is snapped. He used an STM32 microcontroller to drive a brushless motor which he pulled from a hard drive. It totally works, but the nature of the hard drive motor thwarted his original plan. It’s meant to run at very high speeds with low friction. But the thing was never designed to stop on a dime. So when it is directed to turn thirty degrees, it overshoots and oscillates back and forth as shown in the video.
This oscillation would go on for more than ten seconds. But [Petteri] was able to dampen it by adding some friction to the disc. He also had to tweak the original driver design, adding flyback diodes he had forgotten to include, and dealing with some issues caused when feeding a PWM signal to the coils. There are other small defeats which also ate away at him. The paint color doesn’t match the light box he’s using, there were some issues with the battery, and at one point he broke the programming header right off of his PCB. Despite these frustrating issues we still bet it was a lot of fun to work on the project.
Fail of the Week is a Hackaday column which runs every Wednesday. Help keep the fun rolling by writing about your past failures and sending us a link to the story – or sending in links to fail write ups you find in your Internet travels.