# Amount of torque required robot

This is bad and I should know this but I cant seam to figure out if my torque calculation is correct.

Heres the story I am trying to build a robot that will run off of four electric motor one at each wheel. I want it to be able to weight around 25 lbs and be on around 6 inch diameter wheels or .25 ft radius . I want it to be able to run on a small amount of amps as possible and be able to go up a 30 degree slope.

The equation I used was at first to draw FBD and so 25sin30 = 12.5 which would be my force I would have to counteract. then to Torque = f X d = 12.5 X .25 = 3.125 ft*lbs of torque all together so divide by four .78125 ft*lb per wheel or .11kg*m or 11kg*cm which many of the motors are given in.

to me this seams kind of high because tried to compare to torque on a car. I know there are gears in transmission but still didn't add up with my calculations it would be as if the car couldn't make it up the hill thats why I am checking. Am I figuring it wrong that the motor would need that much torque to move it up the slope or what in the world am I doing wrong

Lastly if any of you out there ever built robot and have recommendation for motors let me know I want to keep each motor under 20 dollars but let me know

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