I'm looking to get a motor for an Arduino project in doing, i have a bit of experience with motors but i'm not completely sure what motor i will need for this project is.
I'm looking for a small motor to be able to gut grass with two small 50mm blades. i was using a small 372 g/cm stall torque, 8100 rpm 12v DC motor but that kept stalling when hitting thicker parts of the grass.
I have done some more research and found a motor that might work so i'm not completely sure. Its a NEO 550 Brushless, it 's 0.97 Nm stall torque and 11000 rpm.
I'm still not really sure what motor to use tho, so any help would be appreciated.
You are going down the try it and see if it works. The best solution would be for you to determine what torque and RPM you need to do the job. The choice will also be affected by the forward/reverse speed of the mowing device. Once you have that information with your experience picking a motor should be easy. You also will have to determine how long this is to run, what voltage you will want, what battery chemistry etc you will have to choose the proper battery.
To be frank, I have no idea how you'd measure it other than using the 'guess and check' method, which would probably be costly... :P. I'd say to do research on motors used in commercial products and to take those as the maximum-specced motors that will do that job. Since your project is at a smaller scale, you should be able to go from there to find a lower-specced motor that gets the job done.
Torque is measured in Nm, g/cm is a unit of linear density! I think you intended gf-cm, grams-force-centimeters, if so that would be 0.036Nm.
The 8100rpm is an angular velocity of 850 rad/s, so the max theoretical mechanical power available is 0.036 x 850 = 30W or so. Not unreasonable.
I'm pretty sure you need a lot more torque than that, but probably a much lower angular velocity is fine, so some reduction gearing is indicated to trade speed for torque (ie use a gear motor).
The brushless motor torque is much higher, but again its speed is very high. Its pretty normal for reduction gearing to be needed with an electric motor to increase torque.
