Hey everyone! I am currently working on a cheap gearbox solution to reduce backlash for my high school capstone project. I’d greatly appreciate any and all respondents because the survey will aid in prototyping and development. The survey will only take a few minutes. Thank you!
Form doesn’t work, but cheap and low backlash don’t really go together. You can shim or cross pin gears to eliminate slop between them and the shafts. If you can get tensioning done well, belts and chains can be low backlash, but really low backlash gearboxes often come down to just very high quality gears, or exotic gear types like cycloidals or harmonics. The trick to low backlash mechanisms is to figure out how to not have the gearbox backlash matter. If your gearbox is driving a tiny pinion on very large rack a few degrees of backlash wont matter.
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To add to this linkages can be far less backlash (which includes complient mechanisms), especially if designed carefully like Partrick says, such that the portion of the linkage with the worst backlash doesn’t get used or just gets passed through to another setpoint. This of course includes 4 bars but other linkages as well, such as bell cranks.
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For most FRC gearboxes OTHER than drive systems, your best bet is to spring load the output so all the backlash stays on one side.
For steering systems, you MAY be able to set things up where the feedback path doesn’t have backlash due to interference or flexible members (stuff that doesn’t work well for loaded parts). Belts can be much lower backlash than gears.
For the actual drive path on a gearbox, you are kinda stuck. You need backlash for gear teeth to work right. You can do some compensation in software, where you measure the lash and have the feedback system automatically factor it in when you reverse direction. Fiddly…