I'm an engineering student and I study at an engineering college. Our college has technical festivals. I took part in one last year, I built a robot using 4 dc motors (300 rpm and high torque) and I lost. My opponent has the same motors but she has a better design so I want to increase my motors torque. Could you please advise me - how do I increase the torque of my motors.

  • \$\begingroup\$ The motor you had used, and the one one she had used, both were same? Do you have the datasheet ? If you provide datasheet, the max. Torque can be pr3dicted better. Also, share the drive section of motor... And also may be otHER's if available. \$\endgroup\$
    – User323693
    Mar 3 '17 at 14:07
  • \$\begingroup\$ What drive circuit did you use? What were the motors physically driving? Did the other person use a step down gear hence got more torque. Did your design have faster top speed? Was the other design more likely to burn out motors if the "experiment" had been time extended? What was the experiment in detail. \$\endgroup\$
    – Andy aka
    Mar 3 '17 at 14:07
  • \$\begingroup\$ What makes you sure it's the torque and not the speed you need to increase? What percentage of the unloaded speed was the motor running at? \$\endgroup\$ Mar 3 '17 at 14:12
  • \$\begingroup\$ You can increase the torque of a motor by running it at a higher current. You can increase the speed of a motor by running it at higher voltage. Beware, motors are not simple resistors! \$\endgroup\$
    – Neil_UK
    Mar 3 '17 at 14:20
  • 2
    \$\begingroup\$ Torque is directly related by current, so figure out a way to drive the motor with more current. \$\endgroup\$ Mar 3 '17 at 14:50

You want to find the point where torque and RPM has the highest mechanical power and efficiency. Do this by measuring current vs. torque and speed vs torque.

Using an adjustable torque load such as a small particle brake coupled to the motor shaft, increase the torque load to the motor just to the point where stall occurs. At stall, measure the torque from the brake and the motor current.

Construct a table of the motor mechanical power at various points from no-load to stall torque. Mechanical power output is the product of torque and speed.

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You can plot the measurements and calculated values

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Using the Torque

On the robot the motor is geared down to a usable speed. You want the gear ratio set to give you the optimal mechanical power and efficiency where and when it is needed.

You did not mention the criteria for winning or losing making it difficult to go further.


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