Gear ratio problem


Hi all.
Im now working with the RBX1 robot for my thesis. I need the gear ratio for each step motor in order to calculate the pwm needed. Can someone provides me the ratios?
Thank for reading my post.


Hey Tankt,
You may want to measure the exact ratio using your physical robot or the SolidWorks stl files.
However, by approximation and eyeballing it, I got those ratio which have been precise enough to have the robot move where I want it.
Base rotation : 4 (this is wrong, it’s probably more around 10 or so. Haven’t checked it yet)
Dual base: 5.5
Shoulder: 22.5
Elbow: 1 (kinda weak tho)
Wrist: 4.5
Wrist rotation: 1

Let me know if they don’t work for you.


Thank you for your help. But is the ratio in shoulder 2.25 or 22.5? I found that it might be around 4.8. Any mistake here? Again, thanks for your reply. Im appriciate it.


Hi all
I have calculated all the ratio on the RBX1
Base : 10,67
Dual Nema : 5
Shoulder : 21.5
Elbow : 1
Wrist : 4,67
Wrist rotation : 1
Speacial thanks to Wiwip. Hope you guys can get things done perfectly.