This is kind of a follow on to this thread
The short story is I need to replace a motor because my previous motor stalls and no longer drives my heavier robot. I bought a new motor based on RPM alone, and now I'm concerned that I should have paid more attention to the stall torque. I don't really care how fast the robot goes, but it needs to not stall!
I googled the previous motor, RS-360SH-2885
, and it looks like it has a stall torque of 420 g*cm.
The new motor
has a stall torque of 700 g*cm. I'm using a 9.6 V battery rather that the 12V maximum rating of the motor so that makes my actual stall torque even lower, right?
Other relevant information: the robot currently weighs about 4.5 lbs (2041 g) but I plan on adding an arm and other equipment that should be around 2 pounds for a grand total of 6.5 lbs (2948 g). The wheel radius is about 7 cm. There is a gearbox between the motor and the drive shaft with gear ratios of 10:34, 12:36, and 14:43, for an total ratio of 0.03192.
So if I take 2948g * 7cm I get 20638.8 g*cm. Factoring in the mechanical advantage of my gearbox, I'm down to 903.7, which is well above the stall torque. But that's not quite right because I'm not exactly lifting the whole robot right?
Basically, should I be worried here? I want to make sure I have margin before I go pressing a gear onto this motor shaft. Any insight would be appreciated.