Squirrels have fuzzy tails.

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O say no. Here's my reason: to be on the safe side (and not to loose any RPM), I calculate required torque imagining that bot has to go up 90deg slope (a vertical wall) times two. So, to do that You need to have 110Kg * 7cm * 2 = 770Kg.cm * 2 = 1540Kg.cm of torque. Your motors can deliver stall torque of 30Kg.cm, hence 6 motors will be able to deliver 180Kg.cm torque which is not enough based on my calculations.

Please explain me the calculation..........

and in the arena there will be no slope as shown in above video.

Stall torque required to hold 110Kg at 90deg angle with an arm of 7cm is 110Kg * 7cm = 770Kg.cm. On flat land You need less than that, however, RPM will be very low and motor will be running near it's stall torque drawing loads of current. So, to avoid killing Your motor and to get full RPM available, You have to go for motor with higher torque, hence multiply minimum required torque (770Kg.cm) by 2 (to be on the safe side), but that's only on flat land; if one needs good RPM going up the slope, even higher torque motor would be required.

I don't know why are you calling it arm and at 90*...??

90deg means climbing vertical wall.

Torque When buying a DC motor, there are two torque value ratings which you must pay attention to. The first is operating torque. This is the torque the motor was designed to give. Usually it is the listed torque value. The other rated value is stall torque. This is the torque required to stop the motor from rotating. You normally would want to design using only the operating torque value, but there are occasions when you want to know how far you can push your motor. If you are designing a wheeled robot, good torque means good acceleration. My personal rule is if you have 2 motors on your robot, make sure the stall torque on each is enough to lift the weight of your entire robot times your wheel radius. Always favor torque over velocity. Remember, as stated above, your torque ratings can change depending on the voltage applied. So if you need a little more torque to crush that cute kitten, going 20% above the rated motor voltage value is fairly safe (for you, not the kitten). Just remember that this is less efficient, and that you should heat sink your motor.

hence multiply minimum required torque (770Kg.cm) by 2 (to be on the safe side)

OK, i think i am getting you multiply it by 2???

That's if You want Your robot going up the hill with no (or very small) RPM loss (as a precausion). If Your bot goes on flat only, You can use smaller number to multiply it (say 1.2), however acceleration won't be as good.

How, please explain...................

How what? Sorry, I don't follow You

As per video i think there should be 200RPM at least.