This servo/gearbox is the new and improved version of the original gearbox design (https://bbprojects.technology/collections/stl-fusion-360-source-files/products/3d-printable-high-torque-servo-gear-reduction-files). The original one had a gear ratio of 30:1 and the speed of the output shaft was about 715 RPM which made it difficult to tune in the right PID parameters. This new version has a gear ratio of about 162:1 which lowers the speed and increases the torque of the output shaft.
Double helical gears have been used on this one because they produce a lot less noise than regular spur gears and the forces on the teeth are transferred more gradually. The gears rotate around a 6mm stainless steel shaft which is lubricated with bearing grease. Ideally all the gears should have some bearings, this is being considered for the next moment. Unlike the previous design this one uses 2 20mm bearings to support the output shaft.
The servo uses a 775 36V 9000rpm brushed DC-motor which is driven by a Universal Motion Controller (UMC). The stall torque theoretically is about 297kg/cm. During testing the the servo achieved a torque of about 132kg/cm. None of the gears broke, they were all printed in PLA.
The fusion 360 source file option includes these formats:
-.zip (containing .ipt and .iam files)
Part list, schematics, code and more info about this project can be found here
The 3D-printers, tools and materials I'm using for these projects can be found here: Tools and materials – bbprojects
Note: This is not a physical product. When you're purchasing the STL or Fusion 360 source files you will be able to download these files. A physical product will not be send to your address.
All my designs are licensed according to the CC BY-NC-ND license: https://creativecommons.org/licenses/by-nc-nd/4.0/