Parametric Crowned Pulley for Large Rubber Bands

thingiverse

This part was designed to show how a crowned pulley centers a rubber band. I found a related video at https://www.youtube.com/watch?v=6sM0Qjumyro - it's not my video!\r\n\r\nA new experimental feature is an opening for a captive nut and grub screw that fastens this to a typical FTC shaft. The provided STL file is sized for 1/4" D-Shaft and uses an M3 captive nut.\r\n\r\nThis pulley works with large rubber bands (#105 and #107), but might also work for the next sizes down (such as #92, 93, 94 and 81, 82, 83, 84).\r\n\r\nWhat is it good for? We never used it other than for a demo, but I can imagine a few possibilities, such as an intake device (taking advantage of the tackiness of rubber bands), object movement (use it like a conveyor belt), or a lossy drive transmission (versus a timed belt or chain) to deliberately allow slippage or backlash. It fits neatly inside typical robotics U-Channel stock.\r\n\r\nThe OpenSCAD source script is included for your modifications. The shaft size can be easily changed for 1/4" (6.35 mm) D-Shaft (Actobotics), 6 mm D-Shaft (Gobilda), or 5 mm Hex-Shaft (Rev), and/or tailored for sizing with your printer and slicer.