burningmace
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Calculating minimum torque required to move vehicle up an incline
I'm building a robot of sorts, and need to work out the minimum torque required on the motors to move it up hills. The robot will weigh 15-20kg, and will need to move up inclines of up to 35 degrees at a minimum speed of 0.5m/s, preferably at 2m/s or more though.
The robot has two motors - one powering both the left wheels, one powering the right wheels. The motor is geared to the wheels in a 2:5 ratio via a chain - 8 teeth on the motor, 20 teeth on the wheels.
How do I work out the minimum torque per motor?
The robot has two motors - one powering both the left wheels, one powering the right wheels. The motor is geared to the wheels in a 2:5 ratio via a chain - 8 teeth on the motor, 20 teeth on the wheels.
How do I work out the minimum torque per motor?
Big wheels require lots of torque.
Little wheels require less.
Speed (for a given mass) is related to power, not torque.
What sort of motor do you think you will be using???
Little wheels require less.
Speed (for a given mass) is related to power, not torque.
What sort of motor do you think you will be using???
ASKER
Wheels will be roughly 10cm in diameter. It'll be an electrical motor driving the wheels.
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ASKER
Looks good, but do you know of any suitable motors that aren't steppers? I'm driving my test model with a H-bridge made from power FETs and I don't want the added task of controlling the steppers too.
SOLUTION
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20 * sin(35) ==> 20 * (0.574) ==> 11.74 kg
This force acts on the wheel radius to generate a torque.
What is the radius??
Multiply that number by 2.5 to account for the gearing.
And divide by 2 (the number of motors).