DIY mechatronics always has some unique challenges when relying on simple tools. 3D printing enables some great abilities but high precision gearboxes are still a difficult problem for many. Answering this problem, [Sergei Mishin] has developed a very interesting gearbox solution based on a research paper looking into simple rollers instead of traditional gears. The unique attributes of the design come from the ability to have a compact angled gearbox similar to a bevel gearbox.
Multiple rollers rest on a simple shaft allowing each roller to have independent rotation. This is important because having a circular crown gear for angled transmission creates different rotation speeds. In [Sergei]’s testing, he found that his example gearbox could withstand 9 Nm with the actual adapter breaking before the gearbox showing decent strength.
Of course, how does this differ from a normal bevel gear setup or other 3D printed gearboxes? While 3D printed gears have great flexibility in their simplicity to make, having plastic on plastic is generally very difficult to get precise and long lasting. [Sergei]’s design allows for a highly complex crown gear to take advantage of 3D printing while allowing for simple rollers for improved strength and precision.
While claims of “zero backlash” may be a bit far-fetched, this design still shows great potential in helping make some cool projects. Unique gearboxes are somewhat common here at Hackaday such as this wobbly pericyclic gearbox, but they almost always have a fun spin!
Thanks to [M] for the tip!