how to choice the motor

[manyeap]

hi, may i know about that, how about the gear ratio affect to the performance of the motor?
let said, it is gear 5 is the faster, if compared with the others like gear 10 and so on, but it is less torque than others?

[yonghui]

hi,

higher gear ratio give slower movment but larger torque. lower gear ratio give speed but lower torque. if u wan higher speed and higher torque, use more powerful motor.


rgds
yh

[manyeap]

If now I use this kind of motor, 120Watt DC brush motor http://www.cytron.com.my/viewProduct.php?pcode=9DCP24-120-30G&name=120W%20DC%20Brush%20Motor, which gear ratio is you suggest for me to use?

For example:
Now i would like to build a mobile robot and this robot need to fetch/carry a human (weight 55-60kg). In this robot, I will use two this kind of DC brush motor (DCP24-120-30G-120W) to drive. Therefore, on your professional point of view, which gear ratio is the most suitable to be use?

[A380]

For Robocon 2012 manual robot, Gear-Head 15 is suitable for you all.. The torque is enough to move around 100kg load. By the way, the radius of your wheel will affect your speed and torque too. Higher radius might speed up your robot and the torque will be reduced and vice versa.

120W DKM motor, ratio 15,
http://www.cytron.com.my/viewProduct.ph ... sh%20Motor

[alongpali]

Hello,
I have a problem regarding selecting DC motor.
I would like to build scooter that can carry max load 100kg.
Which is suitable DC motor should I choose?
http://www.cytron.com.my/listProductGro ... QGdc40Y3w=

And how to calculate the required torque?
Is it right with my calculation?

F=force, u= friction force (assume as 1), mass=100kg, g= gravitational force.
T=torque, F=force, r=radiusof wheel (0.1524m)

F=umg
T=Fr

F= (1) (100) (9.81) =980N
T= (980) (0.1524) =149. 352N. m

How much max. speed can it go in km/h?